WIP: Introduce Checker Framework

To be determined: move to a separate profile?

.github/ISSUE_TEMPLATE/bug_report.md

@@ -42,9 +42,9 @@ Please replace this sentence with log output, if applicable.
 <!-- Please complete the following information: -->
 
 - Operating system (e.g. MacOS Monterey).
-- Java version (i.e. `java --version`, e.g. `17.0.10`).
-- Error Prone version (e.g. `2.25.0`).
-- Error Prone Support version (e.g. `0.15.0`).
+- Java version (i.e. `java --version`, e.g. `17.0.8`).
+- Error Prone version (e.g. `2.18.0`).
+- Error Prone Support version (e.g. `0.9.0`).
 
 ### Additional context
 

.github/release.yml

@@ -3,16 +3,16 @@ changelog:
     labels:
       - "ignore-changelog"
   categories:
-    - title: ":warning: Update considerations and deprecations"
-      labels:
-        - "breaking change"
-        - "deprecation"
     - title: ":rocket: New Error Prone checks and Refaster rules"
       labels:
         - "new feature"
     - title: ":sparkles: Improvements"
       labels:
         - "improvement"
+    - title: ":warning: Update considerations and deprecations"
+      labels:
+        - "breaking change"
+        - "deprecation"
     - title: ":bug: Bug fixes"
       labels:
         - "bug"

.github/workflows/build.yml

@@ -10,43 +10,36 @@ jobs:
     strategy:
       matrix:
         os: [ ubuntu-22.04 ]
-        jdk: [ 17.0.10, 21.0.2, 22.0.2 ]
+        jdk: [ 11.0.20, 17.0.8, 21.0.0 ]
         distribution: [ temurin ]
         experimental: [ false ]
         include:
-          - os: macos-14
-            jdk: 17.0.10
+          - os: macos-12
+            jdk: 17.0.8
             distribution: temurin
             experimental: false
           - os: windows-2022
-            jdk: 17.0.10
+            jdk: 17.0.8
             distribution: temurin
             experimental: false
     runs-on: ${{ matrix.os }}
     continue-on-error: ${{ matrix.experimental }}
     steps:
-      - name: Install Harden-Runner
-        uses: step-security/harden-runner@f086349bfa2bd1361f7909c78558e816508cdc10 # v2.8.0
-        with:
-          disable-sudo: true
-          egress-policy: block
-          allowed-endpoints: >
-            api.adoptium.net:443
-            github.com:443
-            jitpack.io:443
-            objects.githubusercontent.com:443
-            repo.maven.apache.org:443
       # We run the build twice for each supported JDK: once against the
       # original Error Prone release, using only Error Prone checks available
       # on Maven Central, and once against the Picnic Error Prone fork,
       # additionally enabling all checks defined in this project and any Error
       # Prone checks available only from other artifact repositories.
-      - name: Check out code and set up JDK and Maven
-        uses: s4u/setup-maven-action@489441643219d2b93ee2a127b2402eb640a1b947 # v1.13.0
+      - name: Check out code
+        uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
+        with:
+          persist-credentials: false
+      - name: Set up JDK
+        uses: actions/setup-java@387ac29b308b003ca37ba93a6cab5eb57c8f5f93 # v4.0.0
         with:
           java-version: ${{ matrix.jdk }}
-          java-distribution: ${{ matrix.distribution }}
-          maven-version: 3.9.6
+          distribution: ${{ matrix.distribution }}
+          cache: maven
       - name: Display build environment details
         run: mvn --version
       - name: Build project against vanilla Error Prone, compile Javadoc

.github/workflows/codeql.yml

@@ -21,32 +21,24 @@ jobs:
       security-events: write
     runs-on: ubuntu-22.04
     steps:
-      - name: Install Harden-Runner
-        uses: step-security/harden-runner@f086349bfa2bd1361f7909c78558e816508cdc10 # v2.8.0
+      - name: Check out code
+        uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
         with:
-          disable-sudo: true
-          egress-policy: block
-          allowed-endpoints: >
-            api.adoptium.net:443
-            api.github.com:443
-            github.com:443
-            objects.githubusercontent.com:443
-            repo.maven.apache.org:443
-            uploads.github.com:443
-      - name: Check out code and set up JDK and Maven
-        uses: s4u/setup-maven-action@489441643219d2b93ee2a127b2402eb640a1b947 # v1.13.0
+          persist-credentials: false
+      - name: Set up JDK
+        uses: actions/setup-java@387ac29b308b003ca37ba93a6cab5eb57c8f5f93 # v4.0.0
         with:
-          java-version: 17.0.10
-          java-distribution: temurin
-          maven-version: 3.9.6
+          java-version: 17.0.8
+          distribution: temurin
+          cache: maven
       - name: Initialize CodeQL
-        uses: github/codeql-action/init@c7f9125735019aa87cfc361530512d50ea439c71 # v3.25.1
+        uses: github/codeql-action/init@407ffafae6a767df3e0230c3df91b6443ae8df75 # v2.22.8
         with:
           languages: ${{ matrix.language }}
       - name: Perform minimal build
         if: matrix.language == 'java'
         run: mvn -T1C clean package -DskipTests -Dverification.skip
       - name: Perform CodeQL analysis
-        uses: github/codeql-action/analyze@c7f9125735019aa87cfc361530512d50ea439c71 # v3.25.1
+        uses: github/codeql-action/analyze@407ffafae6a767df3e0230c3df91b6443ae8df75 # v2.22.8
         with:
           category: /language:${{ matrix.language }}

.github/workflows/deploy-website.yml

@@ -11,43 +11,16 @@ jobs:
   build:
     runs-on: ubuntu-22.04
     steps:
-      - name: Install Harden-Runner
-        uses: step-security/harden-runner@f086349bfa2bd1361f7909c78558e816508cdc10 # v2.8.0
-        with:
-          disable-sudo: true
-          egress-policy: block
-          allowed-endpoints: >
-            api.adoptium.net:443
-            api.github.com:443
-            bestpractices.coreinfrastructure.org:443
-            blog.picnic.nl:443
-            errorprone.info:443
-            github.com:443
-            img.shields.io:443
-            index.rubygems.org:443
-            jitpack.io:443
-            maven.apache.org:443
-            objects.githubusercontent.com:443
-            pitest.org:443
-            repo.maven.apache.org:443
-            rubygems.org:443
-            search.maven.org:443
-            securityscorecards.dev:443
-            sonarcloud.io:443
-            www.baeldung.com:443
-            www.bestpractices.dev:443
-            www.youtube.com:443
-            youtrack.jetbrains.com:443
       - name: Check out code
-        uses: actions/checkout@a5ac7e51b41094c92402da3b24376905380afc29 # v4.1.6
+        uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
         with:
           persist-credentials: false
-      - uses: ruby/setup-ruby@6bd3d993c602f6b675728ebaecb2b569ff86e99b # v1.174.0
+      - uses: ruby/setup-ruby@8575951200e472d5f2d95c625da0c7bec8217c42 # v1.161.0
         with:
           working-directory: ./website
           bundler-cache: true
       - name: Configure Github Pages
-        uses: actions/configure-pages@983d7736d9b0ae728b81ab479565c72886d7745b # v5.0.0
+        uses: actions/configure-pages@1f0c5cde4bc74cd7e1254d0cb4de8d49e9068c7d # v4.0.0
       - name: Generate documentation
         run: ./generate-docs.sh
       - name: Build website with Jekyll
@@ -59,7 +32,7 @@ jobs:
         # "Refaster rules" terminology on our website and in the code.
         run: bundle exec htmlproofer --disable_external true --check-external-hash false ./_site
       - name: Upload website as artifact
-        uses: actions/upload-pages-artifact@56afc609e74202658d3ffba0e8f6dda462b719fa # v3.0.1
+        uses: actions/upload-pages-artifact@0252fc4ba7626f0298f0cf00902a25c6afc77fa8 # v3.0.0
         with:
           path: ./website/_site
   deploy:
@@ -73,13 +46,6 @@ jobs:
       name: github-pages
       url: ${{ steps.deployment.outputs.page_url }}
     steps:
-      - name: Install Harden-Runner
-        uses: step-security/harden-runner@f086349bfa2bd1361f7909c78558e816508cdc10 # v2.8.0
-        with:
-          disable-sudo: true
-          egress-policy: block
-          allowed-endpoints: >
-            api.github.com:443
       - name: Deploy to GitHub Pages
         id: deployment
-        uses: actions/deploy-pages@d6db90164ac5ed86f2b6aed7e0febac5b3c0c03e # v4.0.5
+        uses: actions/deploy-pages@7a9bd943aa5e5175aeb8502edcc6c1c02d398e10 # v4.0.2

.github/workflows/openssf-scorecard.yml

@@ -20,31 +20,17 @@ jobs:
       id-token: write
     runs-on: ubuntu-22.04
     steps:
-      - name: Install Harden-Runner
-        uses: step-security/harden-runner@f086349bfa2bd1361f7909c78558e816508cdc10 # v2.8.0
-        with:
-          disable-sudo: true
-          egress-policy: block
-          allowed-endpoints: >
-            api.github.com:443
-            api.osv.dev:443
-            api.scorecard.dev:443
-            api.securityscorecards.dev:443
-            github.com:443
-            oss-fuzz-build-logs.storage.googleapis.com:443
-            *.sigstore.dev:443
-            www.bestpractices.dev:443
       - name: Check out code
-        uses: actions/checkout@a5ac7e51b41094c92402da3b24376905380afc29 # v4.1.6
+        uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
         with:
           persist-credentials: false
       - name: Run OpenSSF Scorecard analysis
-        uses: ossf/scorecard-action@dc50aa9510b46c811795eb24b2f1ba02a914e534 # v2.3.3
+        uses: ossf/scorecard-action@0864cf19026789058feabb7e87baa5f140aac736 # v2.3.1
         with:
           results_file: results.sarif
           results_format: sarif
           publish_results: ${{ github.ref == 'refs/heads/master' }}
       - name: Update GitHub's code scanning dashboard
-        uses: github/codeql-action/upload-sarif@c7f9125735019aa87cfc361530512d50ea439c71 # v3.25.1
+        uses: github/codeql-action/upload-sarif@407ffafae6a767df3e0230c3df91b6443ae8df75 # v2.22.8
         with:
           sarif_file: results.sarif

.github/workflows/pitest-analyze-pr.yml

@@ -11,23 +11,17 @@ jobs:
   analyze-pr:
     runs-on: ubuntu-22.04
     steps:
-      - name: Install Harden-Runner
-        uses: step-security/harden-runner@f086349bfa2bd1361f7909c78558e816508cdc10 # v2.8.0
+      - name: Check out code
+        uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
         with:
-          disable-sudo: true
-          egress-policy: block
-          allowed-endpoints: >
-            api.adoptium.net:443
-            github.com:443
-            objects.githubusercontent.com:443
-            repo.maven.apache.org:443
-      - name: Check out code and set up JDK and Maven
-        uses: s4u/setup-maven-action@489441643219d2b93ee2a127b2402eb640a1b947 # v1.13.0
+          fetch-depth: 2
+          persist-credentials: false
+      - name: Set up JDK
+        uses: actions/setup-java@387ac29b308b003ca37ba93a6cab5eb57c8f5f93 # v4.0.0
         with:
-          checkout-fetch-depth: 2
-          java-version: 17.0.10
-          java-distribution: temurin
-          maven-version: 3.9.6
+          java-version: 17.0.8
+          distribution: temurin
+          cache: maven
       - name: Run Pitest
         # By running with features `+GIT(from[HEAD~1]), +gitci`, Pitest only
         # analyzes lines changed in the associated pull request, as GitHub
@@ -38,7 +32,7 @@ jobs:
       - name: Aggregate Pitest reports
         run: mvn pitest-git:aggregate -DkilledEmoji=":tada:" -DmutantEmoji=":zombie:" -DtrailingText="Mutation testing report by [Pitest](https://pitest.org/). Review any surviving mutants by inspecting the line comments under [_Files changed_](${{ github.event.number }}/files)."
       - name: Upload Pitest reports as artifact
-        uses: actions/upload-artifact@65462800fd760344b1a7b4382951275a0abb4808 # v4.3.3
+        uses: actions/upload-artifact@c7d193f32edcb7bfad88892161225aeda64e9392 # v4.0.0
         with:
           name: pitest-reports
           path: ./target/pit-reports-ci

.github/workflows/pitest-update-pr.yml

@@ -19,25 +19,18 @@ jobs:
       pull-requests: write
     runs-on: ubuntu-22.04
     steps:
-      - name: Install Harden-Runner
-        uses: step-security/harden-runner@f086349bfa2bd1361f7909c78558e816508cdc10 # v2.8.0
+      - name: Check out code
+        uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
         with:
-          disable-sudo: true
-          egress-policy: block
-          allowed-endpoints: >
-            api.adoptium.net:443
-            api.github.com:443
-            github.com:443
-            objects.githubusercontent.com:443
-            repo.maven.apache.org:443
-      - name: Check out code and set up JDK and Maven
-        uses: s4u/setup-maven-action@489441643219d2b93ee2a127b2402eb640a1b947 # v1.13.0
+          persist-credentials: false
+      - name: Set up JDK
+        uses: actions/setup-java@387ac29b308b003ca37ba93a6cab5eb57c8f5f93 # v4.0.0
         with:
-          java-version: 17.0.10
-          java-distribution: temurin
-          maven-version: 3.9.6
+          java-version: 17.0.8
+          distribution: temurin
+          cache: maven
       - name: Download Pitest analysis artifact
-        uses: dawidd6/action-download-artifact@09f2f74827fd3a8607589e5ad7f9398816f540fe # v3.1.4
+        uses: dawidd6/action-download-artifact@e7466d1a7587ed14867642c2ca74b5bcc1e19a2d # v3.0.0
         with:
           workflow: ${{ github.event.workflow_run.workflow_id }}
           name: pitest-reports

.github/workflows/run-integration-tests.yml

@@ -18,36 +18,26 @@ jobs:
       github.event.issue.pull_request && contains(github.event.comment.body, '/integration-test')
     runs-on: ubuntu-22.04
     steps:
-      - name: Install Harden-Runner
-        uses: step-security/harden-runner@f086349bfa2bd1361f7909c78558e816508cdc10 # v2.8.0
+      - name: Check out code
+        uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
         with:
-          disable-sudo: true
-          egress-policy: block
-          allowed-endpoints: >
-            api.adoptium.net:443
-            checkstyle.org:443
-            github.com:443
-            objects.githubusercontent.com:443
-            oss.sonatype.org:443
-            raw.githubusercontent.com:443
-            repo.maven.apache.org:443
-            repository.sonatype.org:443
-      - name: Check out code and set up JDK and Maven
-        uses: s4u/setup-maven-action@489441643219d2b93ee2a127b2402eb640a1b947 # v1.13.0
+          persist-credentials: false
+          ref: refs/pull/${{ github.event.issue.number }}/head
+      - name: Set up JDK
+        uses: actions/setup-java@387ac29b308b003ca37ba93a6cab5eb57c8f5f93 # v4.0.0
         with:
-          checkout-ref: "refs/pull/${{ github.event.issue.number }}/head"
-          java-version: 17.0.10
-          java-distribution: temurin
-          maven-version: 3.9.6
+          java-version: 17.0.8
+          distribution: temurin
+          cache: maven
       - name: Install project to local Maven repository
         run: mvn -T1C install -DskipTests -Dverification.skip
       - name: Run integration test
-        run: xvfb-run ./integration-tests/checkstyle.sh "${{ runner.temp }}/artifacts"
+        run: xvfb-run ./integration-tests/checkstyle-10.12.4.sh "${{ runner.temp }}/artifacts"
       - name: Upload artifacts on failure
         if: ${{ failure() }}
-        uses: actions/upload-artifact@65462800fd760344b1a7b4382951275a0abb4808 # v4.3.3
+        uses: actions/upload-artifact@c7d193f32edcb7bfad88892161225aeda64e9392 # v4.0.0
         with:
-          name: integration-test-checkstyle
+          name: integration-test-checkstyle-10.12.4
           path: "${{ runner.temp }}/artifacts"
       - name: Remove installed project artifacts
         run: mvn build-helper:remove-project-artifact

.github/workflows/sonarcloud.yml

@@ -13,34 +13,22 @@ jobs:
   analyze:
     # Analysis of code in forked repositories is skipped, as such workflow runs
     # do not have access to the requisite secrets.
-    if: github.event_name != 'pull_request' || github.event.pull_request.head.repo.full_name == github.repository
+    if: github.event.pull_request.head.repo.full_name == github.repository
     permissions:
       contents: read
     runs-on: ubuntu-22.04
     steps:
-      - name: Install Harden-Runner
-        uses: step-security/harden-runner@f086349bfa2bd1361f7909c78558e816508cdc10 # v2.8.0
+      - name: Check out code
+        uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
         with:
-          disable-sudo: true
-          egress-policy: block
-          allowed-endpoints: >
-            analysis-sensorcache-eu-central-1-prod.s3.amazonaws.com:443
-            api.adoptium.net:443
-            api.nuget.org:443
-            ea6ne4j2sb.execute-api.eu-central-1.amazonaws.com:443
-            github.com:443
-            objects.githubusercontent.com:443
-            repo.maven.apache.org:443
-            sc-cleancode-sensorcache-eu-central-1-prod.s3.amazonaws.com:443
-            *.sonarcloud.io:443
-            sonarcloud.io:443
-      - name: Check out code and set up JDK and Maven
-        uses: s4u/setup-maven-action@489441643219d2b93ee2a127b2402eb640a1b947 # v1.13.0
+          fetch-depth: 0
+          persist-credentials: false
+      - name: Set up JDK
+        uses: actions/setup-java@387ac29b308b003ca37ba93a6cab5eb57c8f5f93 # v4.0.0
         with:
-          checkout-fetch-depth: 0
-          java-version: 17.0.10
-          java-distribution: temurin
-          maven-version: 3.9.6
+          java-version: 17.0.8
+          distribution: temurin
+          cache: maven
       - name: Create missing `test` directory
         # XXX: Drop this step in favour of actually having a test.
         run: mkdir refaster-compiler/src/test

.gitignore

@@ -4,7 +4,6 @@
 .DS_Store
 .factorypath
 .idea
-!.idea/icon.svg
 .project
 .settings
 target

.idea/icon.svg

@@ -1,65 +0,0 @@
-<?xml version="1.0" encoding="UTF-8" standalone="no"?>
-<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
-<svg width="100%" height="100%" viewBox="0 0 1259 1199" version="1.1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" xml:space="preserve" xmlns:serif="http://www.serif.com/" style="fill-rule:evenodd;clip-rule:evenodd;stroke-linejoin:round;stroke-miterlimit:2;">
-    <g transform="matrix(1,0,0,1,-624.154,-988.431)">
-        <g transform="matrix(1,0,0,1,-70.1122,-35.0561)">
-            <g transform="matrix(1,0,0,1,0,9.81959)">
-                <path d="M1227.03,1988.79C1237.78,2070.45 1225.83,2190.1 1192.24,2194.53C1158.65,2198.95 1116.14,2086.46 1105.39,2004.81C1094.64,1923.16 1128.44,1902.11 1153.32,1898.84C1178.18,1895.56 1216.28,1907.14 1227.03,1988.79Z" style="fill:rgb(219,220,211);fill-rule:nonzero;"/>
-            </g>
-            <g transform="matrix(1,0,0,1,0,9.81959)">
-                <path d="M1151.08,1881.86C1134.93,1883.99 1114.77,1892.69 1101.6,1913.17C1088.42,1933.64 1082.71,1963.73 1088.42,2007.04C1094.04,2049.75 1107.59,2099.16 1124.51,2138.68C1132.97,2158.45 1142.15,2175.68 1152.59,2188.86C1163.04,2202.05 1176.31,2213.89 1194.48,2211.5C1212.65,2209.11 1222.39,2194.23 1229.07,2178.8C1235.75,2163.36 1240.15,2144.34 1243.21,2123.05C1249.32,2080.5 1249.63,2029.27 1244,1986.56C1238.3,1943.24 1225,1915.66 1206.98,1899.29C1188.95,1882.93 1167.22,1879.74 1151.08,1881.86ZM1155.55,1915.81C1164.27,1914.66 1174.03,1915.62 1183.96,1924.64C1193.89,1933.66 1205.01,1952.69 1210.06,1991.03C1215.18,2029.97 1214.89,2079.4 1209.32,2118.19C1206.53,2137.58 1202.32,2154.4 1197.65,2165.2C1194.14,2173.29 1190.82,2176.3 1189.96,2177.22C1188.89,2176.55 1184.91,2174.51 1179.43,2167.6C1172.12,2158.38 1163.7,2143.22 1155.99,2125.21C1140.57,2089.18 1127.49,2041.51 1122.36,2002.57C1117.32,1964.24 1123.13,1942.97 1130.39,1931.69C1137.65,1920.42 1146.82,1916.96 1155.55,1915.81Z" style="fill:rgb(26,26,26);fill-rule:nonzero;"/>
-            </g>
-            <g transform="matrix(1,0,0,1,0,9.81959)">
-                <path d="M1516.33,1963.1C1466.19,1897.75 1427.4,1906.77 1407.5,1922.05C1387.59,1937.32 1368.84,1972.45 1418.98,2037.8C1431.75,2054.44 1447.26,2071.84 1463.69,2088.19C1495.18,2119.52 1534.33,2139.39 1582.98,2126.14C1606.4,2119.76 1622.19,2110.46 1623.75,2098.64C1625.79,2083.16 1603,2065.78 1569.69,2050.47C1554.75,2019.83 1535.59,1988.2 1516.33,1963.1Z" style="fill:rgb(219,220,211);fill-rule:nonzero;"/>
-            </g>
-            <g transform="matrix(1,0,0,1,0,9.81959)">
-                <path d="M1397.07,1908.46C1409.99,1898.55 1430.41,1890.44 1454.2,1895.61C1478,1900.77 1503.31,1918 1529.91,1952.67C1548.92,1977.44 1567.3,2007.65 1582.28,2037.56C1597.47,2044.87 1610.74,2052.64 1621.09,2061.47C1632.68,2071.35 1642.93,2084.12 1640.73,2100.88C1639.05,2113.64 1630.31,2122.66 1620.9,2128.78C1611.49,2134.9 1600.29,2139.17 1587.48,2142.66C1532.39,2157.66 1485.57,2134.11 1451.61,2100.32C1434.7,2083.49 1418.73,2065.6 1405.39,2048.22C1378.79,2013.56 1368.69,1984.64 1369.86,1960.32C1371.04,1936 1384.15,1918.38 1397.07,1908.46ZM1417.92,1935.63C1410.94,1940.99 1404.71,1948.57 1404.07,1961.97C1403.43,1975.37 1409.02,1996.69 1432.56,2027.38C1444.76,2043.27 1459.82,2060.18 1475.77,2076.05C1504.8,2104.93 1536.26,2121.12 1578.48,2109.62C1589.1,2106.73 1597.5,2103.16 1602.23,2100.08C1605.14,2098.18 1606.16,2096.97 1606.54,2096.46C1606.07,2095.66 1604.57,2092.39 1598.86,2087.52C1591.24,2081.02 1578.31,2073.28 1562.54,2066.03L1556.98,2063.47L1554.29,2057.97C1539.86,2028.35 1521.12,1997.46 1502.75,1973.52C1479.2,1942.84 1460.05,1931.91 1446.94,1929.07C1433.84,1926.23 1424.9,1930.27 1417.92,1935.63Z" style="fill:rgb(26,26,26);fill-rule:nonzero;"/>
-            </g>
-            <g transform="matrix(1,0,0,1,0,9.81959)">
-                <path d="M917.121,1633.14C845.801,1674.32 730.68,1709.07 713.738,1679.73C696.797,1650.39 784.453,1568.07 855.777,1526.89C927.102,1485.71 959.48,1508.89 972.02,1530.62C984.562,1552.34 988.445,1591.97 917.121,1633.14Z" style="fill:rgb(219,220,211);fill-rule:nonzero;"/>
-            </g>
-            <g transform="matrix(1,0,0,1,0,9.81959)">
-                <path d="M986.848,1522.06C978.707,1507.95 962.949,1492.66 938.992,1488.32C915.031,1483.98 885.055,1490.22 847.219,1512.07C809.906,1533.61 769.453,1565.03 739.41,1595.79C724.391,1611.17 711.977,1626.24 703.797,1640.94C695.617,1655.64 689.746,1672.42 698.914,1688.29C708.078,1704.17 725.547,1707.48 742.363,1707.74C759.184,1708.01 778.445,1704.79 799.273,1699.47C840.934,1688.83 888.375,1669.51 925.684,1647.97C963.52,1626.12 983.91,1603.29 992.137,1580.37C1000.36,1557.45 994.988,1536.16 986.848,1522.06ZM957.195,1539.18C961.594,1546.79 964.438,1556.18 959.906,1568.8C955.379,1581.43 942.047,1598.98 908.562,1618.32C874.551,1637.96 828.77,1656.6 790.801,1666.3C771.816,1671.14 754.664,1673.69 742.902,1673.5C734.082,1673.37 730.035,1671.45 728.859,1671C729.062,1669.76 729.426,1665.3 733.715,1657.59C739.434,1647.31 750.215,1633.73 763.906,1619.72C791.285,1591.68 830.324,1561.36 864.336,1541.72C897.824,1522.38 919.695,1519.62 932.895,1522.01C946.09,1524.4 952.797,1531.56 957.195,1539.18Z" style="fill:rgb(26,26,26);fill-rule:nonzero;"/>
-            </g>
-            <g transform="matrix(1,0,0,1,0,9.81959)">
-                <path d="M1791.57,1526.89C1862.89,1568.07 1950.54,1650.39 1933.61,1679.74C1916.66,1709.08 1801.54,1674.33 1730.22,1633.15C1658.9,1591.97 1662.78,1552.34 1675.32,1530.62C1687.86,1508.89 1720.24,1485.72 1791.57,1526.89Z" style="fill:rgb(219,220,211);fill-rule:nonzero;"/>
-            </g>
-            <g transform="matrix(1,0,0,1,0,9.81959)">
-                <path d="M1660.5,1522.06C1652.35,1536.16 1646.98,1557.45 1655.21,1580.37C1663.43,1603.29 1683.82,1626.13 1721.66,1647.97C1758.97,1669.52 1806.41,1688.84 1848.07,1699.48C1868.9,1704.79 1888.16,1708.01 1904.98,1707.75C1921.79,1707.48 1939.27,1704.17 1948.43,1688.3C1957.59,1672.42 1951.73,1655.64 1943.55,1640.94C1935.37,1626.25 1922.95,1611.17 1907.93,1595.79C1877.89,1565.04 1837.43,1533.61 1800.12,1512.07C1762.29,1490.22 1732.31,1483.98 1708.35,1488.32C1684.39,1492.66 1668.64,1507.95 1660.5,1522.06ZM1690.15,1539.18C1694.55,1531.56 1701.25,1524.4 1714.45,1522.02C1727.64,1519.62 1749.52,1522.39 1783,1541.72C1817.02,1561.36 1856.06,1591.68 1883.44,1619.72C1897.12,1633.73 1907.91,1647.32 1913.63,1657.59C1917.92,1665.3 1918.28,1669.77 1918.48,1671.01C1917.31,1671.45 1913.26,1673.37 1904.44,1673.51C1892.68,1673.69 1875.52,1671.15 1856.54,1666.3C1818.57,1656.61 1772.79,1637.96 1738.78,1618.32C1705.29,1598.99 1691.97,1581.43 1687.43,1568.81C1682.91,1556.18 1685.75,1546.8 1690.15,1539.18Z" style="fill:rgb(26,26,26);fill-rule:nonzero;"/>
-            </g>
-            <g transform="matrix(1,0,0,1,0,9.81959)">
-                <path d="M1322.81,1013.67C1058.16,1014.17 843.293,1229.45 843.297,1494.11L843.223,1862.19C843.223,1955.32 919.055,2031.16 1012.19,2031.16C1054.55,2031.16 1093.39,2015.51 1123.09,1989.7C1169.54,2049.44 1242.17,2087.79 1323.7,2087.79C1405.22,2087.79 1477.84,2049.45 1524.28,1989.73C1553.98,2015.52 1592.81,2031.16 1635.15,2031.16C1728.29,2031.16 1804.12,1955.32 1804.12,1862.19L1804.12,1494.1C1804.12,1229.09 1588.7,1013.67 1323.69,1013.67L1322.84,1013.67L1322.81,1013.67ZM1322.92,1068.46L1323.69,1068.46C1559.09,1068.46 1749.33,1258.7 1749.33,1494.11L1749.33,1862.19C1749.33,1925.92 1698.88,1976.37 1635.15,1976.37C1596.91,1976.37 1563.67,1958.03 1542.94,1929.68L1517.91,1895.48L1497,1932.34C1462.85,1992.53 1398.48,2033 1323.7,2033C1248.9,2033 1184.52,1992.51 1150.38,1932.3L1129.45,1895.41L1104.43,1929.65C1083.69,1958.02 1050.44,1976.37 1012.19,1976.37C948.461,1976.37 898.016,1925.93 898.012,1862.2L898.086,1494.11C898.086,1259.03 1087.84,1068.92 1322.92,1068.47L1322.92,1068.46Z" style="fill:rgb(26,26,26);fill-rule:nonzero;"/>
-            </g>
-            <g transform="matrix(1,0,0,1,0,9.81959)">
-                <path d="M1322.86,1041.07C1072.99,1041.54 870.684,1244.23 870.688,1494.11L870.648,1862.19C870.648,1940.62 933.789,2003.77 1012.22,2003.77C1073.65,2003.77 1125.69,1965.03 1145.37,1910.56C1201.73,1934.69 1262.41,1947.14 1323.72,1947.14C1385.02,1947.14 1445.69,1934.69 1502.04,1910.57C1521.72,1965.04 1573.76,2003.77 1635.19,2003.77C1713.62,2003.77 1776.76,1940.62 1776.76,1862.19L1776.76,1494.11C1776.76,1243.9 1573.93,1041.07 1323.72,1041.07L1322.86,1041.07Z" style="fill:white;fill-rule:nonzero;"/>
-            </g>
-            <g transform="matrix(1,0,0,1,0,9.81959)">
-                <path d="M1323.7,1494.1C1449.2,1494.1 1550.24,1595.14 1550.24,1720.64L1550.24,1833.86C1550.24,1959.36 1449.2,2060.4 1323.7,2060.4C1198.2,2060.4 1097.16,1959.36 1097.16,1833.86L1097.16,1720.64C1097.16,1595.14 1198.2,1494.1 1323.7,1494.1Z" style="fill:white;fill-rule:nonzero;"/>
-            </g>
-            <g transform="matrix(1,0,0,1,0,9.81959)">
-                <path d="M1322.86,1041.07C1262.14,1041.18 1204.25,1053.27 1151.36,1075.05C1316.07,1142.87 1432.03,1304.93 1432.03,1494.11L1432.03,1811.95C1432.03,2003.63 1209.62,2024.85 1126.54,1945.82C1177.52,2034.1 1254.55,2060.4 1323.7,2060.4C1408.4,2060.4 1481.95,2014.37 1520.82,1945.86C1546.53,1981.01 1588.08,2003.77 1635.15,2003.77C1713.58,2003.77 1776.72,1940.62 1776.72,1862.19L1776.72,1494.11C1776.72,1243.9 1573.89,1041.07 1323.68,1041.07L1322.86,1041.07Z" style="fill:rgb(219,220,211);fill-rule:nonzero;"/>
-            </g>
-            <g transform="matrix(1,0,0,1,0,9.81959)">
-                <path d="M1322.86,1041.07C1304.33,1041.1 1286.06,1042.28 1268.11,1044.48C1492.04,1071.93 1665.46,1262.75 1665.46,1494.11L1665.46,1862.19C1665.46,1920.85 1630.14,1970.94 1579.54,1992.48C1596.59,1999.74 1615.38,2003.77 1635.15,2003.77C1713.58,2003.77 1776.72,1940.62 1776.72,1862.19L1776.72,1494.11C1776.72,1243.9 1573.89,1041.07 1323.68,1041.07L1322.86,1041.07Z" style="fill:rgb(189,191,175);fill-rule:nonzero;"/>
-            </g>
-            <g transform="matrix(1,0,0,1,0,9.81959)">
-                <path d="M1322.85,1034.22C1069.29,1034.69 863.84,1240.54 863.84,1494.11L863.766,1862.19C863.766,1944.3 930.078,2010.61 1012.19,2010.61C1057.88,2010.61 1098.53,1989.94 1125.71,1957.58C1166.88,2023.5 1240.02,2067.25 1323.7,2067.25C1407.36,2067.25 1480.48,2023.52 1521.66,1957.62C1548.84,1989.96 1589.47,2010.61 1635.15,2010.61C1717.25,2010.61 1783.57,1944.3 1783.57,1862.19L1783.57,1494.11C1783.57,1240.2 1577.59,1034.21 1323.68,1034.22L1322.85,1034.22ZM1322.86,1047.92L1323.68,1047.92C1570.19,1047.92 1769.87,1247.6 1769.87,1494.11L1769.87,1862.19C1769.87,1936.95 1709.91,1996.92 1635.15,1996.92C1590.29,1996.92 1550.82,1975.26 1526.36,1941.82L1520.1,1933.27L1514.87,1942.48C1477.18,2008.91 1405.92,2053.55 1323.7,2053.55C1241.46,2053.55 1170.19,2008.89 1132.5,1942.44L1127.27,1933.21L1121.02,1941.77C1096.56,1975.24 1057.07,1996.92 1012.19,1996.92C937.43,1996.92 877.469,1936.95 877.465,1862.19L877.539,1494.11C877.539,1247.94 1076.7,1048.39 1322.86,1047.92Z" style="fill:rgb(26,26,26);fill-rule:nonzero;"/>
-            </g>
-            <g transform="matrix(1,0,0,1,0,9.81959)">
-                <path d="M1576.29,1470.72C1576.29,1481.36 1568.75,1491.56 1555.31,1499.08C1541.88,1506.6 1523.67,1510.83 1504.68,1510.83C1465.12,1510.83 1433.06,1492.87 1433.06,1470.72C1433.06,1448.57 1465.12,1430.62 1504.68,1430.62C1523.67,1430.62 1541.88,1434.84 1555.31,1442.36C1568.75,1449.89 1576.29,1460.09 1576.29,1470.72Z" style="fill:rgb(255,155,173);fill-rule:nonzero;"/>
-            </g>
-            <g transform="matrix(1,0,0,1,0,9.81959)">
-                <path d="M1214.28,1470.72C1214.28,1481.36 1206.73,1491.56 1193.31,1499.08C1179.87,1506.6 1161.66,1510.83 1142.66,1510.83C1103.11,1510.83 1071.05,1492.87 1071.05,1470.72C1071.05,1448.57 1103.11,1430.62 1142.66,1430.62C1161.66,1430.62 1179.87,1434.84 1193.31,1442.36C1206.73,1449.89 1214.28,1460.09 1214.28,1470.72Z" style="fill:rgb(255,155,173);fill-rule:nonzero;"/>
-            </g>
-            <g transform="matrix(1,0,0,1,0,9.81959)">
-                <path d="M1104.39,1401.46C1104.39,1375.15 1118.45,1350.79 1141.24,1337.63C1164.03,1324.48 1192.16,1324.48 1214.95,1337.63C1237.74,1350.79 1251.81,1375.15 1251.81,1401.46L1224.41,1401.46C1224.41,1384.9 1215.6,1369.64 1201.25,1361.36C1186.9,1353.07 1169.29,1353.07 1154.94,1361.36C1140.59,1369.64 1131.78,1384.9 1131.78,1401.46L1104.39,1401.46Z" style="fill:rgb(26,26,26);fill-rule:nonzero;"/>
-            </g>
-            <g transform="matrix(1,0,0,1,0,9.81959)">
-                <path d="M1395.54,1401.46C1395.54,1375.15 1409.61,1350.79 1432.39,1337.63C1455.18,1324.48 1483.32,1324.48 1506.11,1337.63C1528.89,1350.79 1542.96,1375.15 1542.96,1401.46L1515.56,1401.46C1515.56,1384.9 1506.75,1369.64 1492.41,1361.36C1478.06,1353.07 1460.44,1353.07 1446.09,1361.36C1431.74,1369.64 1422.93,1384.9 1422.93,1401.46L1395.54,1401.46Z" style="fill:rgb(26,26,26);fill-rule:nonzero;"/>
-            </g>
-            <g transform="matrix(1,0,0,1,0,9.81959)">
-                <path d="M1256.81,1448.61C1256.81,1472.48 1269.56,1494.57 1290.24,1506.51C1310.92,1518.45 1336.42,1518.45 1357.1,1506.51C1377.78,1494.57 1390.53,1472.48 1390.53,1448.61L1376.83,1448.61C1376.83,1467.61 1366.71,1485.15 1350.25,1494.65C1333.79,1504.15 1313.55,1504.15 1297.09,1494.65C1280.63,1485.15 1270.51,1467.61 1270.51,1448.61L1256.81,1448.61Z" style="fill:rgb(26,26,26);fill-rule:nonzero;"/>
-            </g>
-        </g>
-    </g>
-</svg>

.renovaterc.json

@@ -12,8 +12,7 @@
       "separateMinorPatch": true
     },
     {
-      "matchPackageNames": [
-        "dawidd6/action-download-artifact",
+      "matchDepNames": [
         "github/codeql-action",
         "ruby/setup-ruby"
       ],

LICENSE.md

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2017-2024 Picnic Technologies BV
+Copyright (c) 2017-2023 Picnic Technologies BV
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

README.md

@@ -49,9 +49,7 @@ high-quality and consistent Java code_][picnic-blog-ep-post].
 ### Installation
 
 This library is built on top of [Error Prone][error-prone-orig-repo]. To use
-it, read the installation guide for Maven or Gradle below. The library requires
-that your build is executed using JDK 17 or above, but supports builds that
-[target][baeldung-java-source-target-options] older versions of Java.
+it, read the installation guide for Maven or Gradle below.
 
 #### Maven
 
@@ -67,8 +65,6 @@ that your build is executed using JDK 17 or above, but supports builds that
                <plugin>
                    <groupId>org.apache.maven.plugins</groupId>
                    <artifactId>maven-compiler-plugin</artifactId>
-                   <!-- Prefer using the latest release. -->
-                   <version>3.12.0</version>
                    <configuration>
                        <annotationProcessorPaths>
                            <!-- Error Prone itself. -->
@@ -98,6 +94,8 @@ that your build is executed using JDK 17 or above, but supports builds that
                            </arg>
                            <arg>-XDcompilePolicy=simple</arg>
                        </compilerArgs>
+                       <!-- Some checks raise warnings rather than errors. -->
+                       <showWarnings>true</showWarnings>
                        <!-- Enable this if you'd like to fail your build upon warnings. -->
                        <!-- <failOnWarning>true</failOnWarning> -->
                    </configuration>
@@ -265,7 +263,6 @@ guidelines][contributing].
 If you want to report a security vulnerability, please do so through a private
 channel; please see our [security policy][security] for details.
 
-[baeldung-java-source-target-options]: https://www.baeldung.com/java-source-target-options
 [bug-checks]: https://github.com/PicnicSupermarket/error-prone-support/blob/master/error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/
 [bug-checks-identity-conversion]: https://github.com/PicnicSupermarket/error-prone-support/blob/master/error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/IdentityConversion.java
 [codeql-badge]: https://github.com/PicnicSupermarket/error-prone-support/actions/workflows/codeql.yml/badge.svg?branch=master&event=push

documentation-support/pom.xml

@@ -5,14 +5,13 @@
     <parent>
         <groupId>tech.picnic.error-prone-support</groupId>
         <artifactId>error-prone-support</artifactId>
-        <version>0.18.0</version>
+        <version>0.14.1-SNAPSHOT</version>
     </parent>
 
     <artifactId>documentation-support</artifactId>
 
     <name>Picnic :: Error Prone Support :: Documentation Support</name>
     <description>Data extraction support for the purpose of documentation generation.</description>
-    <url>https://error-prone.picnic.tech</url>
 
     <dependencies>
         <dependency>
@@ -41,14 +40,6 @@
             <groupId>com.fasterxml.jackson.core</groupId>
             <artifactId>jackson-databind</artifactId>
         </dependency>
-        <dependency>
-            <groupId>com.fasterxml.jackson.datatype</groupId>
-            <artifactId>jackson-datatype-guava</artifactId>
-        </dependency>
-        <dependency>
-            <groupId>com.fasterxml.jackson.module</groupId>
-            <artifactId>jackson-module-parameter-names</artifactId>
-        </dependency>
         <dependency>
             <groupId>com.google.auto</groupId>
             <artifactId>auto-common</artifactId>
@@ -82,8 +73,6 @@
             <artifactId>junit-jupiter-api</artifactId>
             <scope>test</scope>
         </dependency>
-        <!-- XXX: Explicitly declared as a workaround for
-        https://github.com/pitest/pitest-junit5-plugin/issues/105. -->
         <dependency>
             <groupId>org.junit.jupiter</groupId>
             <artifactId>junit-jupiter-engine</artifactId>

documentation-support/src/main/java/tech/picnic/errorprone/documentation/BugPatternExtractor.java

@@ -4,7 +4,6 @@ import static com.google.common.base.Verify.verify;
 import static com.google.common.collect.ImmutableList.toImmutableList;
 import static java.util.Objects.requireNonNull;
 
-import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
 import com.google.auto.common.AnnotationMirrors;
 import com.google.auto.service.AutoService;
 import com.google.auto.value.AutoValue;
@@ -18,7 +17,6 @@ import com.sun.source.tree.AnnotationTree;
 import com.sun.source.tree.ClassTree;
 import com.sun.tools.javac.code.Attribute;
 import com.sun.tools.javac.code.Symbol.ClassSymbol;
-import java.net.URI;
 import java.util.Optional;
 import javax.lang.model.element.AnnotationValue;
 import tech.picnic.errorprone.documentation.BugPatternExtractor.BugPatternDocumentation;
@@ -47,8 +45,7 @@ public final class BugPatternExtractor implements Extractor<BugPatternDocumentat
     }
 
     return Optional.of(
-        BugPatternDocumentation.create(
-            state.getPath().getCompilationUnit().getSourceFile().toUri(),
+        new AutoValue_BugPatternExtractor_BugPatternDocumentation(
             symbol.getQualifiedName().toString(),
             annotation.name().isEmpty() ? tree.getSimpleName().toString() : annotation.name(),
             ImmutableList.copyOf(annotation.altNames()),
@@ -94,36 +91,7 @@ public final class BugPatternExtractor implements Extractor<BugPatternDocumentat
   }
 
   @AutoValue
-  @JsonDeserialize(as = AutoValue_BugPatternExtractor_BugPatternDocumentation.class)
   abstract static class BugPatternDocumentation {
-    static BugPatternDocumentation create(
-        URI source,
-        String fullyQualifiedName,
-        String name,
-        ImmutableList<String> altNames,
-        String link,
-        ImmutableList<String> tags,
-        String summary,
-        String explanation,
-        SeverityLevel severityLevel,
-        boolean canDisable,
-        ImmutableList<String> suppressionAnnotations) {
-      return new AutoValue_BugPatternExtractor_BugPatternDocumentation(
-          source,
-          fullyQualifiedName,
-          name,
-          altNames,
-          link,
-          tags,
-          summary,
-          explanation,
-          severityLevel,
-          canDisable,
-          suppressionAnnotations);
-    }
-
-    abstract URI source();
-
     abstract String fullyQualifiedName();
 
     abstract String name();

documentation-support/src/main/java/tech/picnic/errorprone/documentation/BugPatternTestExtractor.java

@@ -2,15 +2,9 @@ package tech.picnic.errorprone.documentation;
 
 import static com.google.errorprone.matchers.Matchers.instanceMethod;
 import static com.google.errorprone.matchers.method.MethodMatchers.staticMethod;
+import static java.util.Objects.requireNonNull;
 import static java.util.function.Predicate.not;
 
-import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
-import com.fasterxml.jackson.annotation.JsonProperty;
-import com.fasterxml.jackson.annotation.JsonPropertyOrder;
-import com.fasterxml.jackson.annotation.JsonSubTypes;
-import com.fasterxml.jackson.annotation.JsonTypeInfo;
-import com.fasterxml.jackson.annotation.JsonTypeInfo.As;
-import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
 import com.google.auto.service.AutoService;
 import com.google.auto.value.AutoValue;
 import com.google.common.collect.ImmutableList;
@@ -22,10 +16,11 @@ import com.sun.source.tree.ClassTree;
 import com.sun.source.tree.ExpressionTree;
 import com.sun.source.tree.MethodInvocationTree;
 import com.sun.source.util.TreeScanner;
-import java.net.URI;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Objects;
 import java.util.Optional;
+import org.jspecify.annotations.NonNull;
 import org.jspecify.annotations.Nullable;
 import tech.picnic.errorprone.documentation.BugPatternTestExtractor.TestCases;
 
@@ -60,9 +55,7 @@ public final class BugPatternTestExtractor implements Extractor<TestCases> {
         .map(
             tests ->
                 new AutoValue_BugPatternTestExtractor_TestCases(
-                    state.getPath().getCompilationUnit().getSourceFile().toUri(),
-                    ASTHelpers.getSymbol(tree).className(),
-                    tests));
+                    ASTHelpers.getSymbol(tree).className(), tests));
   }
 
   private static final class BugPatternTestCollector
@@ -135,8 +128,8 @@ public final class BugPatternTestExtractor implements Extractor<TestCases> {
       }
 
       ExpressionTree receiver = ASTHelpers.getReceiver(tree);
-      return receiver instanceof MethodInvocationTree methodInvocation
-          ? getClassUnderTest(methodInvocation, state)
+      return receiver instanceof MethodInvocationTree
+          ? getClassUnderTest((MethodInvocationTree) receiver, state)
           : Optional.empty();
     }
 
@@ -154,8 +147,8 @@ public final class BugPatternTestExtractor implements Extractor<TestCases> {
       }
 
       ExpressionTree receiver = ASTHelpers.getReceiver(tree);
-      if (receiver instanceof MethodInvocationTree methodInvocation) {
-        extractIdentificationTestCases(methodInvocation, sink, state);
+      if (receiver instanceof MethodInvocationTree) {
+        extractIdentificationTestCases((MethodInvocationTree) receiver, sink, state);
       }
     }
 
@@ -167,7 +160,7 @@ public final class BugPatternTestExtractor implements Extractor<TestCases> {
          * is safe, because this code is guarded by an earlier call to `#getClassUnderTest(..)`,
          * which ensures that `tree` is part of a longer method invocation chain.
          */
-        MethodInvocationTree inputTree = (MethodInvocationTree) ASTHelpers.getReceiver(tree);
+        MethodInvocationTree inputTree = (MethodInvocationTree) requireNonNull(ASTHelpers.getReceiver(tree));
 
         String path = ASTHelpers.constValue(inputTree.getArguments().get(0), String.class);
         Optional<String> inputCode = getSourceCode(inputTree);
@@ -184,8 +177,8 @@ public final class BugPatternTestExtractor implements Extractor<TestCases> {
       }
 
       ExpressionTree receiver = ASTHelpers.getReceiver(tree);
-      if (receiver instanceof MethodInvocationTree methodInvocation) {
-        extractReplacementTestCases(methodInvocation, sink, state);
+      if (receiver instanceof MethodInvocationTree) {
+        extractReplacementTestCases((MethodInvocationTree) receiver, sink, state);
       }
     }
 
@@ -208,78 +201,32 @@ public final class BugPatternTestExtractor implements Extractor<TestCases> {
   }
 
   @AutoValue
-  @JsonDeserialize(as = AutoValue_BugPatternTestExtractor_TestCases.class)
   abstract static class TestCases {
-    static TestCases create(URI source, String testClass, ImmutableList<TestCase> testCases) {
-      return new AutoValue_BugPatternTestExtractor_TestCases(source, testClass, testCases);
-    }
-
-    abstract URI source();
-
     abstract String testClass();
 
     abstract ImmutableList<TestCase> testCases();
   }
 
   @AutoValue
-  @JsonDeserialize(as = AutoValue_BugPatternTestExtractor_TestCase.class)
   abstract static class TestCase {
-    static TestCase create(String classUnderTest, ImmutableList<TestEntry> entries) {
-      return new AutoValue_BugPatternTestExtractor_TestCase(classUnderTest, entries);
-    }
-
     abstract String classUnderTest();
 
     abstract ImmutableList<TestEntry> entries();
   }
 
-  @JsonSubTypes({
-    @JsonSubTypes.Type(AutoValue_BugPatternTestExtractor_IdentificationTestEntry.class),
-    @JsonSubTypes.Type(AutoValue_BugPatternTestExtractor_ReplacementTestEntry.class)
-  })
-  @JsonTypeInfo(include = As.EXISTING_PROPERTY, property = "type", use = JsonTypeInfo.Id.DEDUCTION)
-  @JsonIgnoreProperties(ignoreUnknown = true)
-  @JsonPropertyOrder("type")
   interface TestEntry {
-    TestType type();
-
     String path();
-
-    enum TestType {
-      IDENTIFICATION,
-      REPLACEMENT
-    }
-  }
-
-  @AutoValue
-  abstract static class IdentificationTestEntry implements TestEntry {
-    static IdentificationTestEntry create(String path, String code) {
-      return new AutoValue_BugPatternTestExtractor_IdentificationTestEntry(path, code);
-    }
-
-    @JsonProperty
-    @Override
-    public final TestType type() {
-      return TestType.IDENTIFICATION;
-    }
-
-    abstract String code();
   }
 
   @AutoValue
   abstract static class ReplacementTestEntry implements TestEntry {
-    static ReplacementTestEntry create(String path, String input, String output) {
-      return new AutoValue_BugPatternTestExtractor_ReplacementTestEntry(path, input, output);
-    }
-
-    @JsonProperty
-    @Override
-    public final TestType type() {
-      return TestType.REPLACEMENT;
-    }
-
     abstract String input();
 
     abstract String output();
   }
+
+  @AutoValue
+  abstract static class IdentificationTestEntry implements TestEntry {
+    abstract String code();
+  }
 }

documentation-support/src/main/java/tech/picnic/errorprone/documentation/DocumentationGenerator.java

@@ -1,6 +1,7 @@
 package tech.picnic.errorprone.documentation;
 
 import static com.google.common.base.Preconditions.checkArgument;
+import static java.util.Objects.requireNonNull;
 
 import com.google.auto.service.AutoService;
 import com.google.common.annotations.VisibleForTesting;
@@ -46,7 +47,7 @@ public final class DocumentationGenerator implements Plugin {
     checkArgument(
         matcher.matches(), "'%s' must be of the form '%s=<value>'", pathArg, OUTPUT_DIRECTORY_FLAG);
 
-    String path = matcher.group(1);
+    String path = requireNonNull(matcher.group(1), "Path must be present");
     try {
       return Path.of(path);
     } catch (InvalidPathException e) {

documentation-support/src/main/java/tech/picnic/errorprone/documentation/DocumentationGeneratorTaskListener.java

@@ -1,5 +1,11 @@
 package tech.picnic.errorprone.documentation;
 
+import static java.nio.charset.StandardCharsets.UTF_8;
+import static java.util.Objects.requireNonNull;
+
+import com.fasterxml.jackson.annotation.JsonAutoDetect.Visibility;
+import com.fasterxml.jackson.annotation.PropertyAccessor;
+import com.fasterxml.jackson.databind.ObjectMapper;
 import com.google.common.collect.ImmutableList;
 import com.google.errorprone.VisitorState;
 import com.sun.source.tree.ClassTree;
@@ -10,7 +16,10 @@ import com.sun.source.util.TaskListener;
 import com.sun.source.util.TreePath;
 import com.sun.tools.javac.api.JavacTrees;
 import com.sun.tools.javac.util.Context;
+import java.io.File;
+import java.io.FileWriter;
 import java.io.IOException;
+import java.io.UncheckedIOException;
 import java.net.URI;
 import java.nio.file.Files;
 import java.nio.file.Path;
@@ -31,6 +40,9 @@ final class DocumentationGeneratorTaskListener implements TaskListener {
               ServiceLoader.load(
                   Extractor.class, DocumentationGeneratorTaskListener.class.getClassLoader()));
 
+  private static final ObjectMapper OBJECT_MAPPER =
+      new ObjectMapper().setVisibility(PropertyAccessor.FIELD, Visibility.ANY);
+
   private final Context context;
   private final Path docsPath;
 
@@ -82,11 +94,19 @@ final class DocumentationGeneratorTaskListener implements TaskListener {
     }
   }
 
-  private <T> void writeToFile(String identifier, String className, T data) {
-    Json.write(docsPath.resolve(String.format("%s-%s.json", identifier, className)), data);
+  private <T extends Object> void writeToFile(String identifier, String className, T data) {
+    File file = docsPath.resolve(String.format("%s-%s.json", identifier, className)).toFile();
+
+    try (FileWriter fileWriter = new FileWriter(file, UTF_8)) {
+      OBJECT_MAPPER.writeValue(fileWriter, data);
+    } catch (IOException e) {
+      throw new UncheckedIOException(String.format("Cannot write to file '%s'", file.getPath()), e);
+    }
   }
 
   private static String getSimpleClassName(URI path) {
-    return Paths.get(path).getFileName().toString().replace(".java", "");
+    return requireNonNull(Paths.get(path).getFileName(), "Path lacks filename")
+        .toString()
+        .replace(".java", "");
   }
 }

documentation-support/src/main/java/tech/picnic/errorprone/documentation/Json.java

@@ -1,45 +0,0 @@
-package tech.picnic.errorprone.documentation;
-
-import com.fasterxml.jackson.annotation.JsonAutoDetect.Visibility;
-import com.fasterxml.jackson.annotation.PropertyAccessor;
-import com.fasterxml.jackson.databind.ObjectMapper;
-import com.fasterxml.jackson.datatype.guava.GuavaModule;
-import com.fasterxml.jackson.module.paramnames.ParameterNamesModule;
-import com.google.errorprone.annotations.FormatMethod;
-import java.io.IOException;
-import java.io.UncheckedIOException;
-import java.nio.file.Path;
-
-/**
- * Utility class that offers mutually consistent JSON serialization and deserialization operations,
- * without further specifying the exact schema used.
- */
-final class Json {
-  private static final ObjectMapper OBJECT_MAPPER =
-      new ObjectMapper()
-          .setVisibility(PropertyAccessor.FIELD, Visibility.ANY)
-          .registerModules(new GuavaModule(), new ParameterNamesModule());
-
-  private Json() {}
-
-  static <T> T read(Path path, Class<T> clazz) {
-    try {
-      return OBJECT_MAPPER.readValue(path.toFile(), clazz);
-    } catch (IOException e) {
-      throw failure(e, "Failure reading from '%s'", path);
-    }
-  }
-
-  static <T> void write(Path path, T object) {
-    try {
-      OBJECT_MAPPER.writeValue(path.toFile(), object);
-    } catch (IOException e) {
-      throw failure(e, "Failure writing to '%s'", path);
-    }
-  }
-
-  @FormatMethod
-  private static UncheckedIOException failure(IOException cause, String format, Object... args) {
-    return new UncheckedIOException(String.format(format, args), cause);
-  }
-}

documentation-support/src/test/java/tech/picnic/errorprone/documentation/BugPatternExtractorTest.java

@@ -1,17 +1,13 @@
 package tech.picnic.errorprone.documentation;
 
-import static com.google.errorprone.BugPattern.SeverityLevel.ERROR;
-import static com.google.errorprone.BugPattern.SeverityLevel.SUGGESTION;
-import static com.google.errorprone.BugPattern.SeverityLevel.WARNING;
+import static java.nio.charset.StandardCharsets.UTF_8;
 import static org.assertj.core.api.Assertions.assertThat;
 
-import com.google.common.collect.ImmutableList;
-import com.google.errorprone.BugPattern;
-import java.net.URI;
+import com.google.common.io.Resources;
+import java.io.IOException;
 import java.nio.file.Path;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.io.TempDir;
-import tech.picnic.errorprone.documentation.BugPatternExtractor.BugPatternDocumentation;
 
 final class BugPatternExtractorTest {
   @Test
@@ -27,7 +23,7 @@ final class BugPatternExtractorTest {
   }
 
   @Test
-  void minimalBugPattern(@TempDir Path outputDirectory) {
+  void minimalBugPattern(@TempDir Path outputDirectory) throws IOException {
     Compilation.compileWithDocumentationGenerator(
         outputDirectory,
         "MinimalBugChecker.java",
@@ -40,25 +36,11 @@ final class BugPatternExtractorTest {
         "@BugPattern(summary = \"MinimalBugChecker summary\", severity = SeverityLevel.ERROR)",
         "public final class MinimalBugChecker extends BugChecker {}");
 
-    verifyGeneratedFileContent(
-        outputDirectory,
-        "MinimalBugChecker",
-        BugPatternDocumentation.create(
-            URI.create("file:///MinimalBugChecker.java"),
-            "pkg.MinimalBugChecker",
-            "MinimalBugChecker",
-            ImmutableList.of(),
-            "",
-            ImmutableList.of(),
-            "MinimalBugChecker summary",
-            "",
-            ERROR,
-            /* canDisable= */ true,
-            ImmutableList.of(SuppressWarnings.class.getCanonicalName())));
+    verifyGeneratedFileContent(outputDirectory, "MinimalBugChecker");
   }
 
   @Test
-  void completeBugPattern(@TempDir Path outputDirectory) {
+  void completeBugPattern(@TempDir Path outputDirectory) throws IOException {
     Compilation.compileWithDocumentationGenerator(
         outputDirectory,
         "CompleteBugChecker.java",
@@ -82,25 +64,11 @@ final class BugPatternExtractorTest {
         "    suppressionAnnotations = {BugPattern.class, Test.class})",
         "public final class CompleteBugChecker extends BugChecker {}");
 
-    verifyGeneratedFileContent(
-        outputDirectory,
-        "CompleteBugChecker",
-        BugPatternDocumentation.create(
-            URI.create("file:///CompleteBugChecker.java"),
-            "pkg.CompleteBugChecker",
-            "OtherName",
-            ImmutableList.of("Check"),
-            "https://error-prone.picnic.tech",
-            ImmutableList.of("Simplification"),
-            "CompleteBugChecker summary",
-            "Example explanation",
-            SUGGESTION,
-            /* canDisable= */ false,
-            ImmutableList.of(BugPattern.class.getCanonicalName(), "org.junit.jupiter.api.Test")));
+    verifyGeneratedFileContent(outputDirectory, "CompleteBugChecker");
   }
 
   @Test
-  void undocumentedSuppressionBugPattern(@TempDir Path outputDirectory) {
+  void undocumentedSuppressionBugPattern(@TempDir Path outputDirectory) throws IOException {
     Compilation.compileWithDocumentationGenerator(
         outputDirectory,
         "UndocumentedSuppressionBugPattern.java",
@@ -116,27 +84,23 @@ final class BugPatternExtractorTest {
         "    documentSuppression = false)",
         "public final class UndocumentedSuppressionBugPattern extends BugChecker {}");
 
-    verifyGeneratedFileContent(
-        outputDirectory,
-        "UndocumentedSuppressionBugPattern",
-        BugPatternDocumentation.create(
-            URI.create("file:///UndocumentedSuppressionBugPattern.java"),
-            "pkg.UndocumentedSuppressionBugPattern",
-            "UndocumentedSuppressionBugPattern",
-            ImmutableList.of(),
-            "",
-            ImmutableList.of(),
-            "UndocumentedSuppressionBugPattern summary",
-            "",
-            WARNING,
-            /* canDisable= */ true,
-            ImmutableList.of()));
+    verifyGeneratedFileContent(outputDirectory, "UndocumentedSuppressionBugPattern");
   }
 
-  private static void verifyGeneratedFileContent(
-      Path outputDirectory, String testClass, BugPatternDocumentation expected) {
-    assertThat(outputDirectory.resolve(String.format("bugpattern-%s.json", testClass)))
-        .exists()
-        .returns(expected, path -> Json.read(path, BugPatternDocumentation.class));
+  private static void verifyGeneratedFileContent(Path outputDirectory, String testClass)
+      throws IOException {
+    String resourceName = String.format("bugpattern-%s.json", testClass);
+    assertThat(outputDirectory.resolve(resourceName))
+        .content(UTF_8)
+        .isEqualToIgnoringWhitespace(
+            getResource(
+                String.join("-", BugPatternExtractorTest.class.getSimpleName(), resourceName)));
+  }
+
+  // XXX: Once we support only JDK 15+, drop this method in favour of including the resources as
+  // text blocks in this class.
+  private static String getResource(String resourceName) throws IOException {
+    return Resources.toString(
+        Resources.getResource(BugPatternExtractorTest.class, resourceName), UTF_8);
   }
 }

documentation-support/src/test/java/tech/picnic/errorprone/documentation/BugPatternTestExtractorTest.java

@@ -1,16 +1,13 @@
 package tech.picnic.errorprone.documentation;
 
+import static java.nio.charset.StandardCharsets.UTF_8;
 import static org.assertj.core.api.Assertions.assertThat;
 
-import com.google.common.collect.ImmutableList;
-import java.net.URI;
+import com.google.common.io.Resources;
+import java.io.IOException;
 import java.nio.file.Path;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.io.TempDir;
-import tech.picnic.errorprone.documentation.BugPatternTestExtractor.IdentificationTestEntry;
-import tech.picnic.errorprone.documentation.BugPatternTestExtractor.ReplacementTestEntry;
-import tech.picnic.errorprone.documentation.BugPatternTestExtractor.TestCase;
-import tech.picnic.errorprone.documentation.BugPatternTestExtractor.TestCases;
 
 final class BugPatternTestExtractorTest {
   @Test
@@ -249,7 +246,7 @@ final class BugPatternTestExtractorTest {
   }
 
   @Test
-  void singleFileCompilationTestHelper(@TempDir Path outputDirectory) {
+  void singleFileCompilationTestHelper(@TempDir Path outputDirectory) throws IOException {
     Compilation.compileWithDocumentationGenerator(
         outputDirectory,
         "SingleFileCompilationTestHelperTest.java",
@@ -266,22 +263,12 @@ final class BugPatternTestExtractorTest {
         "  }",
         "}");
 
-    verifyGeneratedFileContent(
-        outputDirectory,
-        "SingleFileCompilationTestHelperTest",
-        TestCases.create(
-            URI.create("file:///SingleFileCompilationTestHelperTest.java"),
-            "SingleFileCompilationTestHelperTest",
-            ImmutableList.of(
-                TestCase.create(
-                    "SingleFileCompilationTestHelperTest.TestChecker",
-                    ImmutableList.of(
-                        IdentificationTestEntry.create(
-                            "A.java", "// BUG: Diagnostic contains:\nclass A {}\n"))))));
+    verifyGeneratedFileContent(outputDirectory, "SingleFileCompilationTestHelperTest");
   }
 
   @Test
-  void singleFileCompilationTestHelperWithSetArgs(@TempDir Path outputDirectory) {
+  void singleFileCompilationTestHelperWithSetArgs(@TempDir Path outputDirectory)
+      throws IOException {
     Compilation.compileWithDocumentationGenerator(
         outputDirectory,
         "SingleFileCompilationTestHelperWithSetArgsTest.java",
@@ -299,22 +286,11 @@ final class BugPatternTestExtractorTest {
         "  }",
         "}");
 
-    verifyGeneratedFileContent(
-        outputDirectory,
-        "SingleFileCompilationTestHelperWithSetArgsTest",
-        TestCases.create(
-            URI.create("file:///SingleFileCompilationTestHelperWithSetArgsTest.java"),
-            "SingleFileCompilationTestHelperWithSetArgsTest",
-            ImmutableList.of(
-                TestCase.create(
-                    "SingleFileCompilationTestHelperWithSetArgsTest.TestChecker",
-                    ImmutableList.of(
-                        IdentificationTestEntry.create(
-                            "A.java", "// BUG: Diagnostic contains:\nclass A {}\n"))))));
+    verifyGeneratedFileContent(outputDirectory, "SingleFileCompilationTestHelperWithSetArgsTest");
   }
 
   @Test
-  void multiFileCompilationTestHelper(@TempDir Path outputDirectory) {
+  void multiFileCompilationTestHelper(@TempDir Path outputDirectory) throws IOException {
     Compilation.compileWithDocumentationGenerator(
         outputDirectory,
         "MultiFileCompilationTestHelperTest.java",
@@ -332,24 +308,11 @@ final class BugPatternTestExtractorTest {
         "  }",
         "}");
 
-    verifyGeneratedFileContent(
-        outputDirectory,
-        "MultiFileCompilationTestHelperTest",
-        TestCases.create(
-            URI.create("file:///MultiFileCompilationTestHelperTest.java"),
-            "MultiFileCompilationTestHelperTest",
-            ImmutableList.of(
-                TestCase.create(
-                    "MultiFileCompilationTestHelperTest.TestChecker",
-                    ImmutableList.of(
-                        IdentificationTestEntry.create(
-                            "A.java", "// BUG: Diagnostic contains:\nclass A {}\n"),
-                        IdentificationTestEntry.create(
-                            "B.java", "// BUG: Diagnostic contains:\nclass B {}\n"))))));
+    verifyGeneratedFileContent(outputDirectory, "MultiFileCompilationTestHelperTest");
   }
 
   @Test
-  void singleFileBugCheckerRefactoringTestHelper(@TempDir Path outputDirectory) {
+  void singleFileBugCheckerRefactoringTestHelper(@TempDir Path outputDirectory) throws IOException {
     Compilation.compileWithDocumentationGenerator(
         outputDirectory,
         "SingleFileBugCheckerRefactoringTestHelperTest.java",
@@ -367,23 +330,12 @@ final class BugPatternTestExtractorTest {
         "  }",
         "}");
 
-    verifyGeneratedFileContent(
-        outputDirectory,
-        "SingleFileBugCheckerRefactoringTestHelperTest",
-        TestCases.create(
-            URI.create("file:///SingleFileBugCheckerRefactoringTestHelperTest.java"),
-            "SingleFileBugCheckerRefactoringTestHelperTest",
-            ImmutableList.of(
-                TestCase.create(
-                    "SingleFileBugCheckerRefactoringTestHelperTest.TestChecker",
-                    ImmutableList.of(
-                        ReplacementTestEntry.create(
-                            "A.java", "class A {}\n", "class A { /* This is a change. */ }\n"))))));
+    verifyGeneratedFileContent(outputDirectory, "SingleFileBugCheckerRefactoringTestHelperTest");
   }
 
   @Test
   void singleFileBugCheckerRefactoringTestHelperWithSetArgsFixChooserAndCustomTestMode(
-      @TempDir Path outputDirectory) {
+      @TempDir Path outputDirectory) throws IOException {
     Compilation.compileWithDocumentationGenerator(
         outputDirectory,
         "SingleFileBugCheckerRefactoringTestHelperWithSetArgsFixChooserAndCustomTestModeTest.java",
@@ -407,21 +359,11 @@ final class BugPatternTestExtractorTest {
 
     verifyGeneratedFileContent(
         outputDirectory,
-        "SingleFileBugCheckerRefactoringTestHelperWithSetArgsFixChooserAndCustomTestModeTest",
-        TestCases.create(
-            URI.create(
-                "file:///SingleFileBugCheckerRefactoringTestHelperWithSetArgsFixChooserAndCustomTestModeTest.java"),
-            "SingleFileBugCheckerRefactoringTestHelperWithSetArgsFixChooserAndCustomTestModeTest",
-            ImmutableList.of(
-                TestCase.create(
-                    "SingleFileBugCheckerRefactoringTestHelperWithSetArgsFixChooserAndCustomTestModeTest.TestChecker",
-                    ImmutableList.of(
-                        ReplacementTestEntry.create(
-                            "A.java", "class A {}\n", "class A { /* This is a change. */ }\n"))))));
+        "SingleFileBugCheckerRefactoringTestHelperWithSetArgsFixChooserAndCustomTestModeTest");
   }
 
   @Test
-  void multiFileBugCheckerRefactoringTestHelper(@TempDir Path outputDirectory) {
+  void multiFileBugCheckerRefactoringTestHelper(@TempDir Path outputDirectory) throws IOException {
     Compilation.compileWithDocumentationGenerator(
         outputDirectory,
         "MultiFileBugCheckerRefactoringTestHelperTest.java",
@@ -441,24 +383,12 @@ final class BugPatternTestExtractorTest {
         "  }",
         "}");
 
-    verifyGeneratedFileContent(
-        outputDirectory,
-        "MultiFileBugCheckerRefactoringTestHelperTest",
-        TestCases.create(
-            URI.create("file:///MultiFileBugCheckerRefactoringTestHelperTest.java"),
-            "MultiFileBugCheckerRefactoringTestHelperTest",
-            ImmutableList.of(
-                TestCase.create(
-                    "MultiFileBugCheckerRefactoringTestHelperTest.TestChecker",
-                    ImmutableList.of(
-                        ReplacementTestEntry.create(
-                            "A.java", "class A {}\n", "class A { /* This is a change. */ }\n"),
-                        ReplacementTestEntry.create(
-                            "B.java", "class B {}\n", "class B { /* This is a change. */ }\n"))))));
+    verifyGeneratedFileContent(outputDirectory, "MultiFileBugCheckerRefactoringTestHelperTest");
   }
 
   @Test
-  void compilationAndBugCheckerRefactoringTestHelpers(@TempDir Path outputDirectory) {
+  void compilationAndBugCheckerRefactoringTestHelpers(@TempDir Path outputDirectory)
+      throws IOException {
     Compilation.compileWithDocumentationGenerator(
         outputDirectory,
         "CompilationAndBugCheckerRefactoringTestHelpersTest.java",
@@ -482,27 +412,12 @@ final class BugPatternTestExtractorTest {
         "}");
 
     verifyGeneratedFileContent(
-        outputDirectory,
-        "CompilationAndBugCheckerRefactoringTestHelpersTest",
-        TestCases.create(
-            URI.create("file:///CompilationAndBugCheckerRefactoringTestHelpersTest.java"),
-            "CompilationAndBugCheckerRefactoringTestHelpersTest",
-            ImmutableList.of(
-                TestCase.create(
-                    "CompilationAndBugCheckerRefactoringTestHelpersTest.TestChecker",
-                    ImmutableList.of(
-                        IdentificationTestEntry.create(
-                            "A.java", "// BUG: Diagnostic contains:\nclass A {}\n"))),
-                TestCase.create(
-                    "CompilationAndBugCheckerRefactoringTestHelpersTest.TestChecker",
-                    ImmutableList.of(
-                        ReplacementTestEntry.create(
-                            "A.java", "class A {}\n", "class A { /* This is a change. */ }\n"))))));
+        outputDirectory, "CompilationAndBugCheckerRefactoringTestHelpersTest");
   }
 
   @Test
   void compilationAndBugCheckerRefactoringTestHelpersWithCustomCheckerPackageAndNames(
-      @TempDir Path outputDirectory) {
+      @TempDir Path outputDirectory) throws IOException {
     Compilation.compileWithDocumentationGenerator(
         outputDirectory,
         "CompilationAndBugCheckerRefactoringTestHelpersWithCustomCheckerPackageAndNamesTest.java",
@@ -531,28 +446,23 @@ final class BugPatternTestExtractorTest {
 
     verifyGeneratedFileContent(
         outputDirectory,
-        "CompilationAndBugCheckerRefactoringTestHelpersWithCustomCheckerPackageAndNamesTest",
-        TestCases.create(
-            URI.create(
-                "file:///CompilationAndBugCheckerRefactoringTestHelpersWithCustomCheckerPackageAndNamesTest.java"),
-            "pkg.CompilationAndBugCheckerRefactoringTestHelpersWithCustomCheckerPackageAndNamesTest",
-            ImmutableList.of(
-                TestCase.create(
-                    "pkg.CompilationAndBugCheckerRefactoringTestHelpersWithCustomCheckerPackageAndNamesTest.CustomTestChecker",
-                    ImmutableList.of(
-                        IdentificationTestEntry.create(
-                            "A.java", "// BUG: Diagnostic contains:\nclass A {}\n"))),
-                TestCase.create(
-                    "pkg.CompilationAndBugCheckerRefactoringTestHelpersWithCustomCheckerPackageAndNamesTest.CustomTestChecker2",
-                    ImmutableList.of(
-                        ReplacementTestEntry.create(
-                            "A.java", "class A {}\n", "class A { /* This is a change. */ }\n"))))));
+        "CompilationAndBugCheckerRefactoringTestHelpersWithCustomCheckerPackageAndNamesTest");
   }
 
-  private static void verifyGeneratedFileContent(
-      Path outputDirectory, String testClass, TestCases expected) {
-    assertThat(outputDirectory.resolve(String.format("bugpattern-test-%s.json", testClass)))
-        .exists()
-        .returns(expected, path -> Json.read(path, TestCases.class));
+  private static void verifyGeneratedFileContent(Path outputDirectory, String testClass)
+      throws IOException {
+    String resourceName = String.format("bugpattern-test-%s.json", testClass);
+    assertThat(outputDirectory.resolve(resourceName))
+        .content(UTF_8)
+        .isEqualToIgnoringWhitespace(
+            getResource(
+                String.join("-", BugPatternTestExtractorTest.class.getSimpleName(), resourceName)));
+  }
+
+  // XXX: Once we support only JDK 15+, drop this method in favour of including the resources as
+  // text blocks in this class.
+  private static String getResource(String resourceName) throws IOException {
+    return Resources.toString(
+        Resources.getResource(BugPatternTestExtractorTest.class, resourceName), UTF_8);
   }
 }

documentation-support/src/test/java/tech/picnic/errorprone/documentation/Compilation.java

@@ -8,6 +8,8 @@ import com.google.errorprone.FileObjects;
 import com.sun.tools.javac.api.JavacTaskImpl;
 import com.sun.tools.javac.api.JavacTool;
 import com.sun.tools.javac.file.JavacFileManager;
+import java.io.IOException;
+import java.io.UncheckedIOException;
 import java.nio.file.Path;
 import java.util.ArrayList;
 import java.util.List;
@@ -53,22 +55,25 @@ public final class Compilation {
   }
 
   private static void compile(ImmutableList<String> options, JavaFileObject javaFileObject) {
-    JavacFileManager javacFileManager = FileManagers.testFileManager();
-    JavaCompiler compiler = JavacTool.create();
+    try (JavacFileManager javacFileManager = FileManagers.testFileManager()) {
+      JavaCompiler compiler = JavacTool.create();
 
-    List<Diagnostic<?>> diagnostics = new ArrayList<>();
-    JavacTaskImpl task =
-        (JavacTaskImpl)
-            compiler.getTask(
-                null,
-                javacFileManager,
-                diagnostics::add,
-                options,
-                ImmutableList.of(),
-                ImmutableList.of(javaFileObject));
+      List<Diagnostic<?>> diagnostics = new ArrayList<>();
+      JavacTaskImpl task =
+          (JavacTaskImpl)
+              compiler.getTask(
+                  null,
+                  javacFileManager,
+                  diagnostics::add,
+                  options,
+                  ImmutableList.of(),
+                  ImmutableList.of(javaFileObject));
 
-    Boolean result = task.call();
-    assertThat(diagnostics).isEmpty();
-    assertThat(result).isTrue();
+      Boolean result = task.call();
+      assertThat(diagnostics).isEmpty();
+      assertThat(result).isTrue();
+    } catch (IOException e) {
+      throw new UncheckedIOException("Failed to close `JavaCompiler`", e);
+    }
   }
 }

documentation-support/src/test/java/tech/picnic/errorprone/documentation/DocumentationGeneratorTaskListenerTest.java

@@ -93,20 +93,13 @@ final class DocumentationGeneratorTaskListenerTest {
         "DocumentationGeneratorTaskListenerTestClass.java",
         "class DocumentationGeneratorTaskListenerTestClass {}");
 
+    // XXX: Once we support only JDK 15+, use a text block for the `expected` string.
     assertThat(
             outputDirectory.resolve(
                 "documentation-generator-task-listener-test-DocumentationGeneratorTaskListenerTestClass.json"))
         .content(UTF_8)
         .isEqualToIgnoringWhitespace(
-            """
-            {
-              "className": "DocumentationGeneratorTaskListenerTestClass",
-              "path": [
-                "CLASS: DocumentationGeneratorTaskListenerTestClass",
-                "COMPILATION_UNIT"
-              ]
-            }
-            """);
+            "{\"className\":\"DocumentationGeneratorTaskListenerTestClass\",\"path\":[\"CLASS: DocumentationGeneratorTaskListenerTestClass\",\"COMPILATION_UNIT\"]}");
   }
 
   @Immutable
@@ -132,8 +125,8 @@ final class DocumentationGeneratorTaskListenerTest {
     }
 
     private static String describeTree(Tree tree) {
-      return (tree instanceof ClassTree clazz)
-          ? String.join(": ", String.valueOf(tree.getKind()), clazz.getSimpleName())
+      return (tree instanceof ClassTree)
+          ? String.join(": ", String.valueOf(tree.getKind()), ((ClassTree) tree).getSimpleName())
           : tree.getKind().toString();
     }
   }

documentation-support/src/test/java/tech/picnic/errorprone/documentation/JsonTest.java

@@ -1,62 +0,0 @@
-package tech.picnic.errorprone.documentation;
-
-import static java.nio.charset.StandardCharsets.UTF_8;
-import static org.assertj.core.api.Assertions.assertThat;
-import static org.assertj.core.api.Assertions.assertThatThrownBy;
-
-import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
-import com.google.auto.value.AutoValue;
-import java.io.FileNotFoundException;
-import java.io.IOException;
-import java.io.UncheckedIOException;
-import java.nio.file.Files;
-import java.nio.file.Path;
-import org.junit.jupiter.api.Test;
-import org.junit.jupiter.api.io.TempDir;
-
-final class JsonTest {
-  private static final TestObject TEST_OBJECT = new AutoValue_JsonTest_TestObject("foo", 42);
-  private static final String TEST_JSON = "{\"string\":\"foo\",\"number\":42}";
-
-  @Test
-  void write(@TempDir Path directory) {
-    Path file = directory.resolve("test.json");
-
-    Json.write(file, TEST_OBJECT);
-
-    assertThat(file).content(UTF_8).isEqualTo(TEST_JSON);
-  }
-
-  @Test
-  void writeFailure(@TempDir Path directory) {
-    assertThatThrownBy(() -> Json.write(directory, TEST_OBJECT))
-        .isInstanceOf(UncheckedIOException.class)
-        .hasMessageContaining("Failure writing to '%s'", directory)
-        .hasCauseInstanceOf(FileNotFoundException.class);
-  }
-
-  @Test
-  void read(@TempDir Path directory) throws IOException {
-    Path file = directory.resolve("test.json");
-
-    Files.writeString(file, TEST_JSON, UTF_8);
-
-    assertThat(Json.read(file, TestObject.class)).isEqualTo(TEST_OBJECT);
-  }
-
-  @Test
-  void readFailure(@TempDir Path directory) {
-    assertThatThrownBy(() -> Json.read(directory, TestObject.class))
-        .isInstanceOf(UncheckedIOException.class)
-        .hasMessageContaining("Failure reading from '%s'", directory)
-        .hasCauseInstanceOf(FileNotFoundException.class);
-  }
-
-  @AutoValue
-  @JsonDeserialize(as = AutoValue_JsonTest_TestObject.class)
-  abstract static class TestObject {
-    abstract String string();
-
-    abstract int number();
-  }
-}

documentation-support/src/test/resources/tech/picnic/errorprone/documentation/BugPatternExtractorTest-bugpattern-CompleteBugChecker.json

@@ -0,0 +1,19 @@
+{
+  "fullyQualifiedName": "pkg.CompleteBugChecker",
+  "name": "OtherName",
+  "altNames": [
+    "Check"
+  ],
+  "link": "https://error-prone.picnic.tech",
+  "tags": [
+    "Simplification"
+  ],
+  "summary": "CompleteBugChecker summary",
+  "explanation": "Example explanation",
+  "severityLevel": "SUGGESTION",
+  "canDisable": false,
+  "suppressionAnnotations": [
+    "com.google.errorprone.BugPattern",
+    "org.junit.jupiter.api.Test"
+  ]
+}

documentation-support/src/test/resources/tech/picnic/errorprone/documentation/BugPatternExtractorTest-bugpattern-MinimalBugChecker.json

@@ -0,0 +1,14 @@
+{
+  "fullyQualifiedName": "pkg.MinimalBugChecker",
+  "name": "MinimalBugChecker",
+  "altNames": [],
+  "link": "",
+  "tags": [],
+  "summary": "MinimalBugChecker summary",
+  "explanation": "",
+  "severityLevel": "ERROR",
+  "canDisable": true,
+  "suppressionAnnotations": [
+    "java.lang.SuppressWarnings"
+  ]
+}

documentation-support/src/test/resources/tech/picnic/errorprone/documentation/BugPatternExtractorTest-bugpattern-UndocumentedSuppressionBugPattern.json

@@ -0,0 +1,12 @@
+{
+  "fullyQualifiedName": "pkg.UndocumentedSuppressionBugPattern",
+  "name": "UndocumentedSuppressionBugPattern",
+  "altNames": [],
+  "link": "",
+  "tags": [],
+  "summary": "UndocumentedSuppressionBugPattern summary",
+  "explanation": "",
+  "severityLevel": "WARNING",
+  "canDisable": true,
+  "suppressionAnnotations": []
+}

documentation-support/src/test/resources/tech/picnic/errorprone/documentation/BugPatternTestExtractorTest-bugpattern-test-CompilationAndBugCheckerRefactoringTestHelpersTest.json

@@ -0,0 +1,24 @@
+{
+  "testClass": "CompilationAndBugCheckerRefactoringTestHelpersTest",
+  "testCases": [
+    {
+      "classUnderTest": "CompilationAndBugCheckerRefactoringTestHelpersTest.TestChecker",
+      "entries": [
+        {
+          "path": "A.java",
+          "code": "// BUG: Diagnostic contains:\nclass A {}\n"
+        }
+      ]
+    },
+    {
+      "classUnderTest": "CompilationAndBugCheckerRefactoringTestHelpersTest.TestChecker",
+      "entries": [
+        {
+          "path": "A.java",
+          "input": "class A {}\n",
+          "output": "class A { /* This is a change. */ }\n"
+        }
+      ]
+    }
+  ]
+}

documentation-support/src/test/resources/tech/picnic/errorprone/documentation/BugPatternTestExtractorTest-bugpattern-test-CompilationAndBugCheckerRefactoringTestHelpersWithCustomCheckerPackageAndNamesTest.json

@@ -0,0 +1,24 @@
+{
+  "testClass": "pkg.CompilationAndBugCheckerRefactoringTestHelpersWithCustomCheckerPackageAndNamesTest",
+  "testCases": [
+    {
+      "classUnderTest": "pkg.CompilationAndBugCheckerRefactoringTestHelpersWithCustomCheckerPackageAndNamesTest.CustomTestChecker",
+      "entries": [
+        {
+          "path": "A.java",
+          "code": "// BUG: Diagnostic contains:\nclass A {}\n"
+        }
+      ]
+    },
+    {
+      "classUnderTest": "pkg.CompilationAndBugCheckerRefactoringTestHelpersWithCustomCheckerPackageAndNamesTest.CustomTestChecker2",
+      "entries": [
+        {
+          "path": "A.java",
+          "input": "class A {}\n",
+          "output": "class A { /* This is a change. */ }\n"
+        }
+      ]
+    }
+  ]
+}

documentation-support/src/test/resources/tech/picnic/errorprone/documentation/BugPatternTestExtractorTest-bugpattern-test-MultiFileBugCheckerRefactoringTestHelperTest.json

@@ -0,0 +1,20 @@
+{
+  "testClass": "MultiFileBugCheckerRefactoringTestHelperTest",
+  "testCases": [
+    {
+      "classUnderTest": "MultiFileBugCheckerRefactoringTestHelperTest.TestChecker",
+      "entries": [
+        {
+          "path": "A.java",
+          "input": "class A {}\n",
+          "output": "class A { /* This is a change. */ }\n"
+        },
+        {
+          "path": "B.java",
+          "input": "class B {}\n",
+          "output": "class B { /* This is a change. */ }\n"
+        }
+      ]
+    }
+  ]
+}

documentation-support/src/test/resources/tech/picnic/errorprone/documentation/BugPatternTestExtractorTest-bugpattern-test-MultiFileCompilationTestHelperTest.json

@@ -0,0 +1,18 @@
+{
+  "testClass": "MultiFileCompilationTestHelperTest",
+  "testCases": [
+    {
+      "classUnderTest": "MultiFileCompilationTestHelperTest.TestChecker",
+      "entries": [
+        {
+          "path": "A.java",
+          "code": "// BUG: Diagnostic contains:\nclass A {}\n"
+        },
+        {
+          "path": "B.java",
+          "code": "// BUG: Diagnostic contains:\nclass B {}\n"
+        }
+      ]
+    }
+  ]
+}

documentation-support/src/test/resources/tech/picnic/errorprone/documentation/BugPatternTestExtractorTest-bugpattern-test-SingleFileBugCheckerRefactoringTestHelperTest.json

@@ -0,0 +1,15 @@
+{
+  "testClass": "SingleFileBugCheckerRefactoringTestHelperTest",
+  "testCases": [
+    {
+      "classUnderTest": "SingleFileBugCheckerRefactoringTestHelperTest.TestChecker",
+      "entries": [
+        {
+          "path": "A.java",
+          "input": "class A {}\n",
+          "output": "class A { /* This is a change. */ }\n"
+        }
+      ]
+    }
+  ]
+}

documentation-support/src/test/resources/tech/picnic/errorprone/documentation/BugPatternTestExtractorTest-bugpattern-test-SingleFileBugCheckerRefactoringTestHelperWithSetArgsFixChooserAndCustomTestModeTest.json

@@ -0,0 +1,15 @@
+{
+  "testClass": "SingleFileBugCheckerRefactoringTestHelperWithSetArgsFixChooserAndCustomTestModeTest",
+  "testCases": [
+    {
+      "classUnderTest": "SingleFileBugCheckerRefactoringTestHelperWithSetArgsFixChooserAndCustomTestModeTest.TestChecker",
+      "entries": [
+        {
+          "path": "A.java",
+          "input": "class A {}\n",
+          "output": "class A { /* This is a change. */ }\n"
+        }
+      ]
+    }
+  ]
+}

documentation-support/src/test/resources/tech/picnic/errorprone/documentation/BugPatternTestExtractorTest-bugpattern-test-SingleFileCompilationTestHelperTest.json

@@ -0,0 +1,14 @@
+{
+  "testClass": "SingleFileCompilationTestHelperTest",
+  "testCases": [
+    {
+      "classUnderTest": "SingleFileCompilationTestHelperTest.TestChecker",
+      "entries": [
+        {
+          "path": "A.java",
+          "code": "// BUG: Diagnostic contains:\nclass A {}\n"
+        }
+      ]
+    }
+  ]
+}

documentation-support/src/test/resources/tech/picnic/errorprone/documentation/BugPatternTestExtractorTest-bugpattern-test-SingleFileCompilationTestHelperWithSetArgsTest.json

@@ -0,0 +1,14 @@
+{
+  "testClass": "SingleFileCompilationTestHelperWithSetArgsTest",
+  "testCases": [
+    {
+      "classUnderTest": "SingleFileCompilationTestHelperWithSetArgsTest.TestChecker",
+      "entries": [
+        {
+          "path": "A.java",
+          "code": "// BUG: Diagnostic contains:\nclass A {}\n"
+        }
+      ]
+    }
+  ]
+}

error-prone-contrib/pom.xml

@@ -5,14 +5,13 @@
     <parent>
         <groupId>tech.picnic.error-prone-support</groupId>
         <artifactId>error-prone-support</artifactId>
-        <version>0.18.0</version>
+        <version>0.14.1-SNAPSHOT</version>
     </parent>
 
     <artifactId>error-prone-contrib</artifactId>
 
     <name>Picnic :: Error Prone Support :: Contrib</name>
     <description>Extra Error Prone plugins by Picnic.</description>
-    <url>https://error-prone.picnic.tech</url>
 
     <dependencies>
         <dependency>
@@ -48,10 +47,6 @@
             `annotationProcessorPaths` configuration below. -->
             <scope>provided</scope>
         </dependency>
-        <dependency>
-            <groupId>${project.groupId}</groupId>
-            <artifactId>error-prone-utils</artifactId>
-        </dependency>
         <dependency>
             <groupId>${project.groupId}</groupId>
             <artifactId>refaster-support</artifactId>
@@ -65,6 +60,11 @@
         <dependency>
             <groupId>com.fasterxml.jackson.core</groupId>
             <artifactId>jackson-annotations</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>com.google.auto</groupId>
+            <artifactId>auto-common</artifactId>
             <scope>provided</scope>
         </dependency>
         <dependency>
@@ -77,6 +77,10 @@
             <artifactId>auto-value-annotations</artifactId>
             <scope>provided</scope>
         </dependency>
+        <dependency>
+            <groupId>com.google.googlejavaformat</groupId>
+            <artifactId>google-java-format</artifactId>
+        </dependency>
         <dependency>
             <groupId>com.google.guava</groupId>
             <artifactId>guava</artifactId>
@@ -122,11 +126,6 @@
             <artifactId>jakarta.servlet-api</artifactId>
             <scope>test</scope>
         </dependency>
-        <dependency>
-            <groupId>javax.annotation</groupId>
-            <artifactId>javax.annotation-api</artifactId>
-            <scope>provided</scope>
-        </dependency>
         <dependency>
             <groupId>javax.inject</groupId>
             <artifactId>javax.inject</artifactId>
@@ -147,6 +146,10 @@
             <artifactId>assertj-core</artifactId>
             <scope>provided</scope>
         </dependency>
+        <dependency>
+            <groupId>org.checkerframework</groupId>
+            <artifactId>checker-util</artifactId>
+        </dependency>
         <dependency>
             <groupId>org.immutables</groupId>
             <artifactId>value-annotations</artifactId>
@@ -162,8 +165,6 @@
             <artifactId>junit-jupiter-api</artifactId>
             <scope>provided</scope>
         </dependency>
-        <!-- XXX: Explicitly declared as a workaround for
-        https://github.com/pitest/pitest-junit5-plugin/issues/105. -->
         <dependency>
             <groupId>org.junit.jupiter</groupId>
             <artifactId>junit-jupiter-engine</artifactId>
@@ -184,31 +185,6 @@
             <artifactId>mongodb-driver-core</artifactId>
             <scope>test</scope>
         </dependency>
-        <dependency>
-            <groupId>org.openrewrite</groupId>
-            <artifactId>rewrite-core</artifactId>
-            <scope>provided</scope>
-        </dependency>
-        <dependency>
-            <groupId>org.openrewrite</groupId>
-            <artifactId>rewrite-java</artifactId>
-            <scope>provided</scope>
-        </dependency>
-        <dependency>
-            <groupId>org.openrewrite</groupId>
-            <artifactId>rewrite-java-11</artifactId>
-            <scope>test</scope>
-        </dependency>
-        <dependency>
-            <groupId>org.openrewrite</groupId>
-            <artifactId>rewrite-templating</artifactId>
-            <scope>provided</scope>
-        </dependency>
-        <dependency>
-            <groupId>org.openrewrite</groupId>
-            <artifactId>rewrite-test</artifactId>
-            <scope>test</scope>
-        </dependency>
         <dependency>
             <groupId>org.reactivestreams</groupId>
             <artifactId>reactive-streams</artifactId>
@@ -244,11 +220,6 @@
             <artifactId>spring-boot-test</artifactId>
             <scope>provided</scope>
         </dependency>
-        <dependency>
-            <groupId>org.springframework.security</groupId>
-            <artifactId>spring-security-core</artifactId>
-            <scope>test</scope>
-        </dependency>
         <dependency>
             <groupId>org.testng</groupId>
             <artifactId>testng</artifactId>
@@ -264,9 +235,6 @@
                     <artifactId>maven-compiler-plugin</artifactId>
                     <configuration>
                         <annotationProcessorPaths combine.children="append">
-                            <!-- XXX: Drop the version declarations once
-                            properly supported. See
-                            https://youtrack.jetbrains.com/issue/IDEA-342187. -->
                             <path>
                                 <groupId>${project.groupId}</groupId>
                                 <artifactId>documentation-support</artifactId>
@@ -284,6 +252,7 @@
                             </path>
                         </annotationProcessorPaths>
                         <compilerArgs combine.children="append">
+                            <arg>-Xplugin:RefasterRuleCompiler</arg>
                             <arg>-Xplugin:DocumentationGenerator -XoutputDirectory=${project.build.directory}/docs</arg>
                         </compilerArgs>
                     </configuration>

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/AmbiguousJsonCreator.java

@@ -4,7 +4,7 @@ import static com.google.errorprone.BugPattern.LinkType.CUSTOM;
 import static com.google.errorprone.BugPattern.SeverityLevel.WARNING;
 import static com.google.errorprone.BugPattern.StandardTags.LIKELY_ERROR;
 import static com.google.errorprone.matchers.Matchers.isType;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.errorprone.BugPattern;
@@ -18,7 +18,7 @@ import com.google.errorprone.util.ASTHelpers;
 import com.sun.source.tree.AnnotationTree;
 import com.sun.source.tree.ClassTree;
 import com.sun.source.tree.MethodTree;
-import com.sun.source.tree.Tree.Kind;
+import com.sun.source.tree.Tree;
 import com.sun.tools.javac.code.Symbol;
 import java.util.Map;
 import javax.lang.model.element.AnnotationValue;
@@ -46,7 +46,7 @@ public final class AmbiguousJsonCreator extends BugChecker implements Annotation
     }
 
     ClassTree clazz = state.findEnclosing(ClassTree.class);
-    if (clazz == null || clazz.getKind() != Kind.ENUM) {
+    if (clazz == null || clazz.getKind() != Tree.Kind.ENUM) {
       return Description.NO_MATCH;
     }
 

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/AssertJIsNull.java

@@ -8,7 +8,7 @@ import static com.google.errorprone.matchers.Matchers.argument;
 import static com.google.errorprone.matchers.Matchers.argumentCount;
 import static com.google.errorprone.matchers.Matchers.instanceMethod;
 import static com.google.errorprone.matchers.Matchers.nullLiteral;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.errorprone.BugPattern;

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/AssociativeMethodInvocation.java

@@ -1,4 +1,4 @@
-package tech.picnic.errorprone.guidelines.bugpatterns;
+package tech.picnic.errorprone.bugpatterns;
 
 import static com.google.errorprone.BugPattern.LinkType.CUSTOM;
 import static com.google.errorprone.BugPattern.SeverityLevel.SUGGESTION;
@@ -7,7 +7,7 @@ import static com.google.errorprone.matchers.Matchers.allOf;
 import static com.google.errorprone.matchers.Matchers.not;
 import static com.google.errorprone.matchers.Matchers.staticMethod;
 import static com.google.errorprone.matchers.Matchers.toType;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.common.collect.ImmutableSet;
@@ -27,7 +27,7 @@ import com.google.errorprone.util.ASTHelpers;
 import com.sun.source.tree.ExpressionTree;
 import com.sun.source.tree.MethodInvocationTree;
 import com.sun.tools.javac.code.Type;
-import tech.picnic.errorprone.utils.SourceCode;
+import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 
 /**
  * A {@link BugChecker} that flags unnecessarily nested usage of methods that implement an
@@ -36,8 +36,6 @@ import tech.picnic.errorprone.utils.SourceCode;
  * <p>The arguments to such methods can be flattened without affecting semantics, while making the
  * code more readable.
  */
-// XXX: Move this check to the `error-prone-contrib` module once it also covers non-Error Prone
-// methods.
 @AutoService(BugChecker.class)
 @BugPattern(
     summary =

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/AutowiredConstructor.java

@@ -6,7 +6,7 @@ import static com.google.errorprone.BugPattern.StandardTags.SIMPLIFICATION;
 import static com.google.errorprone.matchers.ChildMultiMatcher.MatchType.AT_LEAST_ONE;
 import static com.google.errorprone.matchers.Matchers.annotations;
 import static com.google.errorprone.matchers.Matchers.isType;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.common.collect.Iterables;
@@ -23,7 +23,7 @@ import com.sun.source.tree.ClassTree;
 import com.sun.source.tree.MethodTree;
 import com.sun.source.tree.Tree;
 import java.util.List;
-import tech.picnic.errorprone.utils.SourceCode;
+import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 
 /** A {@link BugChecker} that flags redundant {@code @Autowired} constructor annotations. */
 @AutoService(BugChecker.class)

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/CanonicalAnnotationSyntax.java

@@ -3,7 +3,7 @@ package tech.picnic.errorprone.bugpatterns;
 import static com.google.errorprone.BugPattern.LinkType.CUSTOM;
 import static com.google.errorprone.BugPattern.SeverityLevel.SUGGESTION;
 import static com.google.errorprone.BugPattern.StandardTags.SIMPLIFICATION;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.common.collect.ImmutableSet;
@@ -19,13 +19,14 @@ import com.sun.source.tree.AnnotationTree;
 import com.sun.source.tree.AssignmentTree;
 import com.sun.source.tree.ExpressionTree;
 import com.sun.source.tree.NewArrayTree;
+import com.sun.source.tree.Tree.Kind;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Optional;
 import java.util.function.BiFunction;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
-import tech.picnic.errorprone.utils.SourceCode;
+import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 
 /** A {@link BugChecker} that flags annotations that could be written more concisely. */
 @AutoService(BugChecker.class)
@@ -118,7 +119,7 @@ public final class CanonicalAnnotationSyntax extends BugChecker implements Annot
        * the expression as a whole.
        */
       ExpressionTree value =
-          (arg instanceof AssignmentTree assignment) ? assignment.getExpression() : arg;
+          (arg.getKind() == Kind.ASSIGNMENT) ? ((AssignmentTree) arg).getExpression() : arg;
 
       /* Store a fix for each expression that was successfully simplified. */
       simplifyAttributeValue(value, state)
@@ -129,10 +130,13 @@ public final class CanonicalAnnotationSyntax extends BugChecker implements Annot
   }
 
   private static Optional<String> simplifyAttributeValue(ExpressionTree expr, VisitorState state) {
-    /* Drop curly braces or commas if possible. */
-    return expr instanceof NewArrayTree newArray
-        ? simplifySingletonArray(newArray, state).or(() -> dropTrailingComma(newArray, state))
-        : Optional.empty();
+    if (expr.getKind() != Kind.NEW_ARRAY) {
+      /* There are no curly braces or commas to be dropped here. */
+      return Optional.empty();
+    }
+
+    NewArrayTree array = (NewArrayTree) expr;
+    return simplifySingletonArray(array, state).or(() -> dropTrailingComma(array, state));
   }
 
   /** Returns the expression describing the array's sole element, if any. */

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/CanonicalClassNameUsage.java

@@ -9,7 +9,7 @@ import static com.google.errorprone.matchers.Matchers.classLiteral;
 import static com.google.errorprone.matchers.Matchers.instanceMethod;
 import static com.google.errorprone.matchers.Matchers.receiverOfInvocation;
 import static com.google.errorprone.matchers.Matchers.toType;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.errorprone.BugPattern;
@@ -81,8 +81,9 @@ public final class CanonicalClassNameUsage extends BugChecker
       path = path.getParentPath();
     }
 
-    return path.getLeaf() instanceof MethodInvocationTree methodInvocation
-        && isOwnedByCanonicalNameUsingType(ASTHelpers.getSymbol(methodInvocation));
+    return path.getLeaf() instanceof MethodInvocationTree
+        && isOwnedByCanonicalNameUsingType(
+            ASTHelpers.getSymbol((MethodInvocationTree) path.getLeaf()));
   }
 
   private static boolean isOwnedByCanonicalNameUsingType(MethodSymbol symbol) {

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/CollectorMutability.java

@@ -4,7 +4,7 @@ import static com.google.errorprone.BugPattern.LinkType.CUSTOM;
 import static com.google.errorprone.BugPattern.SeverityLevel.WARNING;
 import static com.google.errorprone.BugPattern.StandardTags.FRAGILE_CODE;
 import static com.google.errorprone.matchers.method.MethodMatchers.staticMethod;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.common.collect.ImmutableList;
@@ -25,7 +25,7 @@ import java.util.HashMap;
 import java.util.HashSet;
 import java.util.stream.Collector;
 import java.util.stream.Collectors;
-import tech.picnic.errorprone.utils.ThirdPartyLibrary;
+import tech.picnic.errorprone.bugpatterns.util.ThirdPartyLibrary;
 
 /**
  * A {@link BugChecker} that flags {@link Collector Collectors} that don't clearly express

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/DirectReturn.java

@@ -11,7 +11,7 @@ import static com.google.errorprone.matchers.Matchers.not;
 import static com.google.errorprone.matchers.Matchers.returnStatement;
 import static com.google.errorprone.matchers.Matchers.staticMethod;
 import static com.google.errorprone.matchers.Matchers.toType;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.common.collect.Streams;
@@ -39,8 +39,8 @@ import com.sun.tools.javac.code.Symbol;
 import java.util.List;
 import java.util.Optional;
 import org.jspecify.annotations.Nullable;
-import tech.picnic.errorprone.utils.MoreASTHelpers;
-import tech.picnic.errorprone.utils.SourceCode;
+import tech.picnic.errorprone.bugpatterns.util.MoreASTHelpers;
+import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 
 /**
  * A {@link BugChecker} that flags unnecessary local variable assignments preceding a return
@@ -101,17 +101,19 @@ public final class DirectReturn extends BugChecker implements BlockTreeMatcher {
   }
 
   private static Optional<ExpressionTree> tryMatchAssignment(Symbol targetSymbol, Tree tree) {
-    if (tree instanceof ExpressionStatementTree expressionStatement) {
-      return tryMatchAssignment(targetSymbol, expressionStatement.getExpression());
+    if (tree instanceof ExpressionStatementTree) {
+      return tryMatchAssignment(targetSymbol, ((ExpressionStatementTree) tree).getExpression());
     }
 
-    if (tree instanceof AssignmentTree assignment) {
+    if (tree instanceof AssignmentTree) {
+      AssignmentTree assignment = (AssignmentTree) tree;
       return targetSymbol.equals(ASTHelpers.getSymbol(assignment.getVariable()))
           ? Optional.of(assignment.getExpression())
           : Optional.empty();
     }
 
-    if (tree instanceof VariableTree declaration) {
+    if (tree instanceof VariableTree) {
+      VariableTree declaration = (VariableTree) tree;
       return declaration.getModifiers().getAnnotations().isEmpty()
               && targetSymbol.equals(ASTHelpers.getSymbol(declaration))
           ? Optional.ofNullable(declaration.getInitializer())
@@ -149,11 +151,11 @@ public final class DirectReturn extends BugChecker implements BlockTreeMatcher {
             Streams.stream(state.getPath()).skip(1),
             Streams.stream(state.getPath()),
             (tree, child) -> {
-              if (!(tree instanceof TryTree tryTree)) {
+              if (!(tree instanceof TryTree)) {
                 return null;
               }
 
-              BlockTree finallyBlock = tryTree.getFinallyBlock();
+              BlockTree finallyBlock = ((TryTree) tree).getFinallyBlock();
               return !child.equals(finallyBlock) ? finallyBlock : null;
             })
         .anyMatch(finallyBlock -> referencesIdentifierSymbol(symbol, finallyBlock));

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/EmptyMethod.java

@@ -7,7 +7,7 @@ import static com.google.errorprone.matchers.ChildMultiMatcher.MatchType.AT_LEAS
 import static com.google.errorprone.matchers.Matchers.annotations;
 import static com.google.errorprone.matchers.Matchers.anyOf;
 import static com.google.errorprone.matchers.Matchers.isType;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.errorprone.BugPattern;
@@ -21,7 +21,7 @@ import com.sun.source.tree.ClassTree;
 import com.sun.source.tree.MethodTree;
 import com.sun.source.tree.Tree;
 import java.util.Optional;
-import tech.picnic.errorprone.utils.SourceCode;
+import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 
 /** A {@link BugChecker} that flags empty methods that seemingly can simply be deleted. */
 @AutoService(BugChecker.class)

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/EmptyMonoZip.java

@@ -1,89 +0,0 @@
-package tech.picnic.errorprone.bugpatterns;
-
-import static com.google.errorprone.BugPattern.LinkType.CUSTOM;
-import static com.google.errorprone.BugPattern.SeverityLevel.ERROR;
-import static com.google.errorprone.BugPattern.StandardTags.LIKELY_ERROR;
-import static com.google.errorprone.matchers.Matchers.anyOf;
-import static com.google.errorprone.matchers.Matchers.instanceMethod;
-import static com.google.errorprone.matchers.Matchers.staticMethod;
-import static com.google.errorprone.matchers.Matchers.typePredicateMatcher;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
-import static tech.picnic.errorprone.utils.MoreTypePredicates.isSubTypeOf;
-import static tech.picnic.errorprone.utils.MoreTypes.generic;
-import static tech.picnic.errorprone.utils.MoreTypes.type;
-
-import com.google.auto.service.AutoService;
-import com.google.errorprone.BugPattern;
-import com.google.errorprone.VisitorState;
-import com.google.errorprone.bugpatterns.BugChecker;
-import com.google.errorprone.bugpatterns.BugChecker.MethodInvocationTreeMatcher;
-import com.google.errorprone.matchers.Description;
-import com.google.errorprone.matchers.Matcher;
-import com.google.errorprone.suppliers.Supplier;
-import com.google.errorprone.suppliers.Suppliers;
-import com.sun.source.tree.ExpressionTree;
-import com.sun.source.tree.MemberSelectTree;
-import com.sun.source.tree.MethodInvocationTree;
-import com.sun.tools.javac.code.Type;
-import reactor.core.publisher.Mono;
-
-/**
- * A {@link BugChecker} that flags {@link Mono#zip} and {@link Mono#zipWith} invocations with a
- * {@code Mono<Void>} or {@link Mono#empty()} argument or receiver.
- *
- * <p>When a zipped reactive stream completes empty, then the other zipped streams will be cancelled
- * (or not subscribed to), and the operation as a whole will complete empty as well. This is
- * generally not what was intended.
- */
-// XXX: Generalize this check to also cover `Flux` zip operations.
-@AutoService(BugChecker.class)
-@BugPattern(
-    summary = "Don't pass a `Mono<Void>` or `Mono.empty()` argument to `Mono#{zip,With}`",
-    link = BUG_PATTERNS_BASE_URL + "EmptyMonoZip",
-    linkType = CUSTOM,
-    severity = ERROR,
-    tags = LIKELY_ERROR)
-public final class EmptyMonoZip extends BugChecker implements MethodInvocationTreeMatcher {
-  private static final long serialVersionUID = 1L;
-  private static final Supplier<Type> MONO =
-      Suppliers.typeFromString("reactor.core.publisher.Mono");
-  private static final Matcher<ExpressionTree> MONO_ZIP_OR_ZIP_WITH =
-      anyOf(
-          instanceMethod().onDescendantOf(MONO).named("zipWith"),
-          staticMethod().onClass(MONO).named("zip"));
-  private static final Matcher<ExpressionTree> EMPTY_MONO =
-      anyOf(
-          staticMethod().onDescendantOf(MONO).named("empty"),
-          typePredicateMatcher(isSubTypeOf(generic(MONO, type(Void.class.getCanonicalName())))));
-
-  /** Instantiates a new {@link EmptyMonoZip} instance. */
-  public EmptyMonoZip() {}
-
-  @Override
-  public Description matchMethodInvocation(MethodInvocationTree tree, VisitorState state) {
-    if (!MONO_ZIP_OR_ZIP_WITH.matches(tree, state)) {
-      return Description.NO_MATCH;
-    }
-
-    if (hasEmptyReceiver(tree, state)) {
-      return buildDescription(tree)
-          .setMessage("Invoking `Mono#zipWith` on `Mono#empty()` or a `Mono<Void>` is a no-op")
-          .build();
-    }
-
-    if (hasEmptyArguments(tree, state)) {
-      return describeMatch(tree);
-    }
-
-    return Description.NO_MATCH;
-  }
-
-  private static boolean hasEmptyReceiver(MethodInvocationTree tree, VisitorState state) {
-    return tree.getMethodSelect() instanceof MemberSelectTree memberSelect
-        && EMPTY_MONO.matches(memberSelect.getExpression(), state);
-  }
-
-  private static boolean hasEmptyArguments(MethodInvocationTree tree, VisitorState state) {
-    return tree.getArguments().stream().anyMatch(arg -> EMPTY_MONO.matches(arg, state));
-  }
-}

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/ErrorProneRuntimeClasspath.java

@@ -1,11 +1,11 @@
-package tech.picnic.errorprone.guidelines.bugpatterns;
+package tech.picnic.errorprone.bugpatterns;
 
 import static com.google.common.collect.ImmutableSet.toImmutableSet;
 import static com.google.errorprone.BugPattern.LinkType.CUSTOM;
 import static com.google.errorprone.BugPattern.SeverityLevel.SUGGESTION;
 import static com.google.errorprone.BugPattern.StandardTags.FRAGILE_CODE;
 import static com.google.errorprone.matchers.Matchers.instanceMethod;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.common.collect.ImmutableSet;
@@ -28,7 +28,7 @@ import com.sun.tools.javac.code.Symbol;
 import com.sun.tools.javac.code.Symbol.ClassSymbol;
 import com.sun.tools.javac.util.Constants;
 import java.util.regex.Pattern;
-import tech.picnic.errorprone.utils.ThirdPartyLibrary;
+import tech.picnic.errorprone.bugpatterns.util.ThirdPartyLibrary;
 
 /**
  * A {@link BugChecker} that flags literal strings in Error Prone Support code that represent the
@@ -50,9 +50,8 @@ import tech.picnic.errorprone.utils.ThirdPartyLibrary;
 @AutoService(BugChecker.class)
 @BugPattern(
     summary =
-        """
-        Prefer `Class#getCanonicalName()` over an equivalent string literal if and only if the \
-        type will be on the runtime classpath""",
+        "Prefer `Class#getCanonicalName()` over an equivalent string literal if and only if the "
+            + "type will be on the runtime classpath",
     link = BUG_PATTERNS_BASE_URL + "ErrorProneRuntimeClasspath",
     linkType = CUSTOM,
     severity = SUGGESTION,

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/ErrorProneTestHelperSourceFormat.java

@@ -1,4 +1,4 @@
-package tech.picnic.errorprone.guidelines.bugpatterns;
+package tech.picnic.errorprone.bugpatterns;
 
 import static com.google.errorprone.BugPattern.LinkType.CUSTOM;
 import static com.google.errorprone.BugPattern.SeverityLevel.SUGGESTION;
@@ -7,7 +7,7 @@ import static com.google.errorprone.matchers.Matchers.anyOf;
 import static com.google.errorprone.matchers.Matchers.instanceMethod;
 import static com.google.errorprone.matchers.Matchers.staticMethod;
 import static java.util.stream.Collectors.joining;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.common.base.Splitter;

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/ExplicitEnumOrdering.java

@@ -7,7 +7,7 @@ import static com.google.errorprone.BugPattern.SeverityLevel.WARNING;
 import static com.google.errorprone.BugPattern.StandardTags.FRAGILE_CODE;
 import static com.google.errorprone.matchers.method.MethodMatchers.staticMethod;
 import static java.util.stream.Collectors.collectingAndThen;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.common.collect.ImmutableSet;
@@ -72,7 +72,7 @@ public final class ExplicitEnumOrdering extends BugChecker implements MethodInvo
       List<? extends ExpressionTree> expressions) {
     return expressions.stream()
         .map(ASTHelpers::getSymbol)
-        .filter(s -> s != null && s.isEnum())
+        .filter(Symbol::isEnum)
         .collect(
             collectingAndThen(
                 toImmutableSetMultimap(Symbol::asType, Symbol::toString),

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/FluxFlatMapUsage.java

@@ -4,11 +4,11 @@ import static com.google.errorprone.BugPattern.LinkType.CUSTOM;
 import static com.google.errorprone.BugPattern.SeverityLevel.ERROR;
 import static com.google.errorprone.BugPattern.StandardTags.LIKELY_ERROR;
 import static com.google.errorprone.matchers.method.MethodMatchers.instanceMethod;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
-import static tech.picnic.errorprone.utils.MoreTypes.generic;
-import static tech.picnic.errorprone.utils.MoreTypes.subOf;
-import static tech.picnic.errorprone.utils.MoreTypes.type;
-import static tech.picnic.errorprone.utils.MoreTypes.unbound;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.MoreTypes.generic;
+import static tech.picnic.errorprone.bugpatterns.util.MoreTypes.subOf;
+import static tech.picnic.errorprone.bugpatterns.util.MoreTypes.type;
+import static tech.picnic.errorprone.bugpatterns.util.MoreTypes.unbound;
 
 import com.google.auto.service.AutoService;
 import com.google.common.collect.Iterables;
@@ -50,9 +50,8 @@ import reactor.core.publisher.Flux;
 @AutoService(BugChecker.class)
 @BugPattern(
     summary =
-        """
-        `Flux#flatMap` and `Flux#flatMapSequential` have subtle semantics; please use \
-        `Flux#concatMap` or explicitly specify the desired amount of concurrency""",
+        "`Flux#flatMap` and `Flux#flatMapSequential` have subtle semantics; "
+            + "please use `Flux#concatMap` or explicitly specify the desired amount of concurrency",
     link = BUG_PATTERNS_BASE_URL + "FluxFlatMapUsage",
     linkType = CUSTOM,
     severity = ERROR,

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/FluxImplicitBlock.java

@@ -6,7 +6,7 @@ import static com.google.errorprone.BugPattern.SeverityLevel.WARNING;
 import static com.google.errorprone.BugPattern.StandardTags.CONCURRENCY;
 import static com.google.errorprone.BugPattern.StandardTags.PERFORMANCE;
 import static com.google.errorprone.matchers.method.MethodMatchers.instanceMethod;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.common.collect.ImmutableList;
@@ -27,7 +27,7 @@ import com.sun.tools.javac.code.Type;
 import com.sun.tools.javac.util.Position;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
-import tech.picnic.errorprone.utils.ThirdPartyLibrary;
+import tech.picnic.errorprone.bugpatterns.util.ThirdPartyLibrary;
 
 /**
  * A {@link BugChecker} that flags {@link reactor.core.publisher.Flux} operator usages that may

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/FormatStringConcatenation.java

@@ -10,7 +10,7 @@ import static com.google.errorprone.matchers.Matchers.instanceMethod;
 import static com.google.errorprone.matchers.Matchers.not;
 import static com.google.errorprone.matchers.Matchers.staticMethod;
 import static java.util.stream.Collectors.joining;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.common.base.Preconditions;
@@ -31,12 +31,13 @@ import com.sun.source.tree.ParenthesizedTree;
 import com.sun.source.tree.Tree;
 import com.sun.source.tree.Tree.Kind;
 import com.sun.source.util.SimpleTreeVisitor;
+import com.sun.tools.javac.code.Type;
 import java.util.ArrayList;
 import java.util.Formatter;
 import java.util.List;
 import java.util.Optional;
 import org.jspecify.annotations.Nullable;
-import tech.picnic.errorprone.utils.SourceCode;
+import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 
 /**
  * A {@link BugChecker} that flags string concatenations that produce a format string; in such cases
@@ -208,7 +209,9 @@ public final class FormatStringConcatenation extends BugChecker
   }
 
   private static boolean isStringTyped(ExpressionTree tree, VisitorState state) {
-    return ASTHelpers.isSameType(ASTHelpers.getType(tree), state.getSymtab().stringType, state);
+    // XXX: Open Error Prone PR to improve the `@Nullable` annotations on `ASTHelpers`.
+    Type type = ASTHelpers.getType(tree);
+    return type != null && ASTHelpers.isSameType(type, state.getSymtab().stringType, state);
   }
 
   private static class ReplacementArgumentsConstructor
@@ -245,8 +248,8 @@ public final class FormatStringConcatenation extends BugChecker
     }
 
     private void appendExpression(Tree tree) {
-      if (tree instanceof LiteralTree literal) {
-        formatString.append(literal.getValue());
+      if (tree instanceof LiteralTree) {
+        formatString.append(((LiteralTree) tree).getValue());
       } else {
         formatString.append(formatSpecifier);
         formatArguments.add(tree);

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/IdentityConversion.java

@@ -7,7 +7,7 @@ import static com.google.errorprone.BugPattern.StandardTags.SIMPLIFICATION;
 import static com.google.errorprone.matchers.Matchers.anyOf;
 import static com.google.errorprone.matchers.Matchers.staticMethod;
 import static com.google.errorprone.suppliers.Suppliers.OBJECT_TYPE;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.common.collect.ImmutableBiMap;
@@ -41,7 +41,7 @@ import com.sun.tools.javac.code.Type;
 import com.sun.tools.javac.code.Types;
 import java.util.Arrays;
 import java.util.List;
-import tech.picnic.errorprone.utils.SourceCode;
+import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 
 /** A {@link BugChecker} that flags redundant identity conversions. */
 // XXX: Consider detecting cases where a flagged expression is passed to a method, and where removal
@@ -124,9 +124,8 @@ public final class IdentityConversion extends BugChecker implements MethodInvoca
 
     return buildDescription(tree)
         .setMessage(
-            """
-            This method invocation appears redundant; remove it or suppress this warning and add a \
-            comment explaining its purpose""")
+            "This method invocation appears redundant; remove it or suppress this warning and "
+                + "add a comment explaining its purpose")
         .addFix(SuggestedFix.replace(tree, SourceCode.treeToString(sourceTree, state)))
         .addFix(SuggestedFixes.addSuppressWarnings(state, canonicalName()))
         .build();

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/ImmutablesSortedSetComparator.java

@@ -11,7 +11,7 @@ import static com.google.errorprone.matchers.Matchers.hasModifier;
 import static com.google.errorprone.matchers.Matchers.isSubtypeOf;
 import static com.google.errorprone.matchers.Matchers.methodReturns;
 import static com.google.errorprone.matchers.Matchers.not;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.errorprone.BugPattern;
@@ -43,9 +43,8 @@ import javax.lang.model.element.Modifier;
 @AutoService(BugChecker.class)
 @BugPattern(
     summary =
-        """
-        `SortedSet` properties of a `@Value.Immutable` or `@Value.Modifiable` type must be \
-        annotated with `@Value.NaturalOrder` or `@Value.ReverseOrder`""",
+        "`SortedSet` properties of a `@Value.Immutable` or `@Value.Modifiable` type must be "
+            + "annotated with `@Value.NaturalOrder` or `@Value.ReverseOrder`",
     link = BUG_PATTERNS_BASE_URL + "ImmutablesSortedSetComparator",
     linkType = CUSTOM,
     severity = ERROR,

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/IsInstanceLambdaUsage.java

@@ -3,7 +3,7 @@ package tech.picnic.errorprone.bugpatterns;
 import static com.google.errorprone.BugPattern.LinkType.CUSTOM;
 import static com.google.errorprone.BugPattern.SeverityLevel.SUGGESTION;
 import static com.google.errorprone.BugPattern.StandardTags.SIMPLIFICATION;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.common.collect.Iterables;
@@ -16,15 +16,17 @@ import com.google.errorprone.matchers.Description;
 import com.google.errorprone.util.ASTHelpers;
 import com.sun.source.tree.InstanceOfTree;
 import com.sun.source.tree.LambdaExpressionTree;
+import com.sun.source.tree.Tree.Kind;
 import com.sun.source.tree.VariableTree;
-import tech.picnic.errorprone.utils.SourceCode;
+import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 
 /**
  * A {@link BugChecker} that flags lambda expressions that can be replaced with a method reference
  * of the form {@code T.class::isInstance}.
+ *
+ * @see MethodReferenceUsage
  */
-// XXX: Consider folding this logic into the `MethodReferenceUsage` check of the
-// `error-prone-experimental` module.
+// XXX: Consider folding this logic into the `MethodReferenceUsage` check.
 @AutoService(BugChecker.class)
 @BugPattern(
     summary = "Prefer `Class::isInstance` method reference over equivalent lambda expression",
@@ -40,12 +42,12 @@ public final class IsInstanceLambdaUsage extends BugChecker implements LambdaExp
 
   @Override
   public Description matchLambdaExpression(LambdaExpressionTree tree, VisitorState state) {
-    if (tree.getParameters().size() != 1
-        || !(tree.getBody() instanceof InstanceOfTree instanceOf)) {
+    if (tree.getParameters().size() != 1 || tree.getBody().getKind() != Kind.INSTANCE_OF) {
       return Description.NO_MATCH;
     }
 
     VariableTree param = Iterables.getOnlyElement(tree.getParameters());
+    InstanceOfTree instanceOf = (InstanceOfTree) tree.getBody();
     if (!ASTHelpers.getSymbol(param).equals(ASTHelpers.getSymbol(instanceOf.getExpression()))) {
       return Description.NO_MATCH;
     }

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/JUnitClassModifiers.java

@@ -11,9 +11,9 @@ import static com.google.errorprone.matchers.Matchers.hasMethod;
 import static com.google.errorprone.matchers.Matchers.hasModifier;
 import static com.google.errorprone.matchers.Matchers.isType;
 import static com.google.errorprone.matchers.Matchers.not;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
-import static tech.picnic.errorprone.utils.MoreJUnitMatchers.TEST_METHOD;
-import static tech.picnic.errorprone.utils.MoreMatchers.hasMetaAnnotation;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.MoreJUnitMatchers.TEST_METHOD;
+import static tech.picnic.errorprone.bugpatterns.util.MoreMatchers.hasMetaAnnotation;
 
 import com.google.auto.service.AutoService;
 import com.google.common.collect.ImmutableSet;

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/JUnitMethodDeclaration.java

@@ -8,9 +8,9 @@ import static com.google.errorprone.matchers.Matchers.enclosingClass;
 import static com.google.errorprone.matchers.Matchers.hasModifier;
 import static com.google.errorprone.matchers.Matchers.not;
 import static java.util.function.Predicate.not;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
-import static tech.picnic.errorprone.utils.MoreJUnitMatchers.SETUP_OR_TEARDOWN_METHOD;
-import static tech.picnic.errorprone.utils.MoreJUnitMatchers.TEST_METHOD;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.MoreJUnitMatchers.SETUP_OR_TEARDOWN_METHOD;
+import static tech.picnic.errorprone.bugpatterns.util.MoreJUnitMatchers.TEST_METHOD;
 
 import com.google.auto.service.AutoService;
 import com.google.common.collect.ImmutableSet;
@@ -28,7 +28,7 @@ import com.sun.source.tree.MethodTree;
 import com.sun.tools.javac.code.Symbol.MethodSymbol;
 import java.util.Optional;
 import javax.lang.model.element.Modifier;
-import tech.picnic.errorprone.utils.ConflictDetection;
+import tech.picnic.errorprone.bugpatterns.util.ConflictDetection;
 
 /** A {@link BugChecker} that flags non-canonical JUnit method declarations. */
 // XXX: Consider introducing a class-level check that enforces that test classes:

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/JUnitNullaryParameterizedTestDeclaration.java

@@ -7,8 +7,8 @@ import static com.google.errorprone.matchers.ChildMultiMatcher.MatchType.AT_LEAS
 import static com.google.errorprone.matchers.Matchers.annotations;
 import static com.google.errorprone.matchers.Matchers.anyOf;
 import static com.google.errorprone.matchers.Matchers.isType;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
-import static tech.picnic.errorprone.utils.MoreMatchers.hasMetaAnnotation;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.MoreMatchers.hasMetaAnnotation;
 
 import com.google.auto.service.AutoService;
 import com.google.errorprone.BugPattern;
@@ -23,7 +23,7 @@ import com.google.errorprone.matchers.MultiMatcher;
 import com.google.errorprone.matchers.MultiMatcher.MultiMatchResult;
 import com.sun.source.tree.AnnotationTree;
 import com.sun.source.tree.MethodTree;
-import tech.picnic.errorprone.utils.SourceCode;
+import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 
 /**
  * A {@link BugChecker} that flags nullary {@link

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/JUnitValueSource.java

@@ -19,9 +19,9 @@ import static com.google.errorprone.matchers.Matchers.staticMethod;
 import static com.google.errorprone.matchers.Matchers.toType;
 import static java.util.function.Predicate.not;
 import static java.util.stream.Collectors.joining;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
-import static tech.picnic.errorprone.utils.MoreJUnitMatchers.HAS_METHOD_SOURCE;
-import static tech.picnic.errorprone.utils.MoreJUnitMatchers.getMethodSourceFactoryNames;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.MoreJUnitMatchers.HAS_METHOD_SOURCE;
+import static tech.picnic.errorprone.bugpatterns.util.MoreJUnitMatchers.getMethodSourceFactoryNames;
 
 import com.google.auto.service.AutoService;
 import com.google.common.collect.ImmutableList;
@@ -58,7 +58,7 @@ import java.util.stream.IntStream;
 import java.util.stream.LongStream;
 import java.util.stream.Stream;
 import org.jspecify.annotations.Nullable;
-import tech.picnic.errorprone.utils.SourceCode;
+import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 
 /**
  * A {@link BugChecker} that flags JUnit tests with a {@link
@@ -171,6 +171,9 @@ public final class JUnitValueSource extends BugChecker implements MethodTreeMatc
     return findMatchingSibling(tree, m -> m.getName().contentEquals(methodName), state);
   }
 
+  // XXX: File ticket for the `@SuppressWarnings`: the checker incorrectly claims that the predicate
+  // only accepts `@InternedDistinct @SignatureBottom MethodTree` values (IIUC).
+  @SuppressWarnings({"interning:argument", "signature:argument"})
   private static Optional<MethodTree> findMatchingSibling(
       MethodTree tree, Predicate<? super MethodTree> predicate, VisitorState state) {
     return state.findEnclosing(ClassTree.class).getMembers().stream()
@@ -232,7 +235,7 @@ public final class JUnitValueSource extends BugChecker implements MethodTreeMatc
       @Override
       public @Nullable Void visitReturn(ReturnTree node, @Nullable Void unused) {
         returnExpressions.add(node.getExpression());
-        return super.visitReturn(node, null);
+        return super.visitReturn(node, unused);
       }
 
       @Override
@@ -265,8 +268,8 @@ public final class JUnitValueSource extends BugChecker implements MethodTreeMatc
             arguments.stream()
                 .map(
                     arg ->
-                        arg instanceof MethodInvocationTree methodInvocation
-                            ? Iterables.getOnlyElement(methodInvocation.getArguments())
+                        arg instanceof MethodInvocationTree
+                            ? Iterables.getOnlyElement(((MethodInvocationTree) arg).getArguments())
                             : arg)
                 .map(argument -> SourceCode.treeToString(argument, state))
                 .collect(joining(", ")))
@@ -276,12 +279,16 @@ public final class JUnitValueSource extends BugChecker implements MethodTreeMatc
   private static String toValueSourceAttributeName(Type type) {
     String typeString = type.tsym.name.toString();
 
-    return switch (typeString) {
-      case "Class" -> "classes";
-      case "Character" -> "chars";
-      case "Integer" -> "ints";
-      default -> typeString.toLowerCase(Locale.ROOT) + 's';
-    };
+    switch (typeString) {
+      case "Class":
+        return "classes";
+      case "Character":
+        return "chars";
+      case "Integer":
+        return "ints";
+      default:
+        return typeString.toLowerCase(Locale.ROOT) + 's';
+    }
   }
 
   private static <T> Optional<T> getElementIfSingleton(Collection<T> collection) {
@@ -293,10 +300,11 @@ public final class JUnitValueSource extends BugChecker implements MethodTreeMatc
   private static Matcher<ExpressionTree> isSingleDimensionArrayCreationWithAllElementsMatching(
       Matcher<? super ExpressionTree> elementMatcher) {
     return (tree, state) -> {
-      if (!(tree instanceof NewArrayTree newArray)) {
+      if (!(tree instanceof NewArrayTree)) {
         return false;
       }
 
+      NewArrayTree newArray = (NewArrayTree) tree;
       return newArray.getDimensions().isEmpty()
           && !newArray.getInitializers().isEmpty()
           && newArray.getInitializers().stream()

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/LexicographicalAnnotationAttributeListing.java

@@ -7,7 +7,7 @@ import static com.google.errorprone.BugPattern.StandardTags.STYLE;
 import static java.util.Comparator.comparing;
 import static java.util.Comparator.naturalOrder;
 import static java.util.stream.Collectors.joining;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.common.base.Splitter;
@@ -31,6 +31,7 @@ import com.sun.source.tree.LiteralTree;
 import com.sun.source.tree.NewArrayTree;
 import com.sun.source.tree.PrimitiveTypeTree;
 import com.sun.source.tree.Tree;
+import com.sun.source.tree.Tree.Kind;
 import com.sun.source.util.TreeScanner;
 import com.sun.tools.javac.code.Symtab;
 import com.sun.tools.javac.code.Type;
@@ -41,9 +42,9 @@ import java.util.Set;
 import java.util.stream.Stream;
 import javax.inject.Inject;
 import org.jspecify.annotations.Nullable;
-import tech.picnic.errorprone.utils.AnnotationAttributeMatcher;
-import tech.picnic.errorprone.utils.Flags;
-import tech.picnic.errorprone.utils.SourceCode;
+import tech.picnic.errorprone.bugpatterns.util.AnnotationAttributeMatcher;
+import tech.picnic.errorprone.bugpatterns.util.Flags;
+import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 
 /**
  * A {@link BugChecker} that flags annotation array listings which aren't sorted lexicographically.
@@ -51,9 +52,6 @@ import tech.picnic.errorprone.utils.SourceCode;
  * <p>The idea behind this checker is that maintaining a sorted sequence simplifies conflict
  * resolution, and can even avoid it if two branches add the same entry.
  */
-// XXX: In some places we declare a `@SuppressWarnings` annotation with a final value of
-// `key-to-resolve-AnnotationUseStyle-and-TrailingComment-check-conflict`. That entry must stay
-// last. Consider adding (generic?) support for such cases.
 @AutoService(BugChecker.class)
 @BugPattern(
     summary = "Where possible, sort annotation array attributes lexicographically",
@@ -67,15 +65,14 @@ public final class LexicographicalAnnotationAttributeListing extends BugChecker
   private static final long serialVersionUID = 1L;
   private static final ImmutableSet<String> BLACKLISTED_ANNOTATIONS =
       ImmutableSet.of(
-          // XXX: Unless `JsonPropertyOrder#alphabetic` is true...
+          // XXX: unless JsonPropertyOrder#alphabetic is true...
           "com.fasterxml.jackson.annotation.JsonPropertyOrder#value",
           "io.swagger.annotations.ApiImplicitParams#value",
           "io.swagger.v3.oas.annotations.Parameters#value",
           "javax.xml.bind.annotation.XmlType#propOrder",
           "org.springframework.context.annotation.PropertySource#value",
           "org.springframework.test.context.TestPropertySource#locations",
-          "org.springframework.test.context.TestPropertySource#value",
-          "picocli.CommandLine.Option#names");
+          "org.springframework.test.context.TestPropertySource#value");
   private static final String FLAG_PREFIX = "LexicographicalAnnotationAttributeListing:";
   private static final String INCLUDED_ANNOTATIONS_FLAG = FLAG_PREFIX + "Includes";
   private static final String EXCLUDED_ANNOTATIONS_FLAG = FLAG_PREFIX + "Excludes";
@@ -125,9 +122,13 @@ public final class LexicographicalAnnotationAttributeListing extends BugChecker
   }
 
   private static Optional<NewArrayTree> extractArray(ExpressionTree expr) {
-    return expr instanceof AssignmentTree assignment
-        ? extractArray(assignment.getExpression())
-        : Optional.of(expr).filter(NewArrayTree.class::isInstance).map(NewArrayTree.class::cast);
+    if (expr.getKind() == Kind.ASSIGNMENT) {
+      return extractArray(((AssignmentTree) expr).getExpression());
+    }
+
+    return Optional.of(expr)
+        .filter(e -> e.getKind() == Kind.NEW_ARRAY)
+        .map(NewArrayTree.class::cast);
   }
 
   private static Optional<SuggestedFix.Builder> suggestSorting(
@@ -192,24 +193,24 @@ public final class LexicographicalAnnotationAttributeListing extends BugChecker
       @Override
       public @Nullable Void visitIdentifier(IdentifierTree node, @Nullable Void unused) {
         nodes.add(ImmutableList.of(node.getName().toString()));
-        return super.visitIdentifier(node, null);
+        return super.visitIdentifier(node, unused);
       }
 
       @Override
       public @Nullable Void visitLiteral(LiteralTree node, @Nullable Void unused) {
         Object value = ASTHelpers.constValue(node);
         nodes.add(
-            value instanceof String str
-                ? STRING_ARGUMENT_SPLITTER.splitToStream(str).collect(toImmutableList())
+            value instanceof String
+                ? STRING_ARGUMENT_SPLITTER.splitToStream((String) value).collect(toImmutableList())
                 : ImmutableList.of(String.valueOf(value)));
 
-        return super.visitLiteral(node, null);
+        return super.visitLiteral(node, unused);
       }
 
       @Override
       public @Nullable Void visitPrimitiveType(PrimitiveTypeTree node, @Nullable Void unused) {
         nodes.add(ImmutableList.of(node.getPrimitiveTypeKind().toString()));
-        return super.visitPrimitiveType(node, null);
+        return super.visitPrimitiveType(node, unused);
       }
     }.scan(array, null);
 

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/LexicographicalAnnotationListing.java

@@ -7,7 +7,7 @@ import static com.google.errorprone.BugPattern.StandardTags.STYLE;
 import static com.sun.tools.javac.code.TypeAnnotations.AnnotationType.DECLARATION;
 import static com.sun.tools.javac.code.TypeAnnotations.AnnotationType.TYPE;
 import static java.util.Comparator.comparing;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.common.base.VerifyException;
@@ -28,7 +28,7 @@ import com.sun.tools.javac.code.TypeAnnotations.AnnotationType;
 import java.util.Comparator;
 import java.util.List;
 import org.jspecify.annotations.Nullable;
-import tech.picnic.errorprone.utils.SourceCode;
+import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 
 /**
  * A {@link BugChecker} that flags annotations that are not lexicographically sorted.
@@ -36,10 +36,6 @@ import tech.picnic.errorprone.utils.SourceCode;
  * <p>The idea behind this checker is that maintaining a sorted sequence simplifies conflict
  * resolution, and can even avoid it if two branches add the same annotation.
  */
-// XXX: Currently this checker only flags method-level annotations. It should likely also flag
-// type-, field- and parameter-level annotations.
-// XXX: Duplicate entries are often a mistake. Consider introducing a similar `BugChecker` that
-// flags duplicates.
 @AutoService(BugChecker.class)
 @BugPattern(
     summary = "Sort annotations lexicographically where possible",

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/MethodReferenceUsage.java

@@ -1,10 +1,10 @@
-package tech.picnic.errorprone.experimental.bugpatterns;
+package tech.picnic.errorprone.bugpatterns;
 
 import static com.google.common.collect.ImmutableList.toImmutableList;
 import static com.google.errorprone.BugPattern.LinkType.CUSTOM;
 import static com.google.errorprone.BugPattern.SeverityLevel.SUGGESTION;
 import static com.google.errorprone.BugPattern.StandardTags.STYLE;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.common.base.VerifyException;
@@ -27,15 +27,19 @@ import com.sun.source.tree.MethodInvocationTree;
 import com.sun.source.tree.ParenthesizedTree;
 import com.sun.source.tree.ReturnTree;
 import com.sun.source.tree.Tree;
+import com.sun.source.tree.Tree.Kind;
 import com.sun.source.tree.VariableTree;
 import com.sun.tools.javac.code.Symbol;
 import com.sun.tools.javac.code.Type;
 import java.util.List;
 import java.util.Optional;
 import javax.lang.model.element.Name;
+import org.checkerframework.checker.nullness.qual.NonNull;
 
 /**
  * A {@link BugChecker} that flags lambda expressions that can be replaced with method references.
+ *
+ * @see IsInstanceLambdaUsage
  */
 // XXX: Other custom expressions we could rewrite:
 // - `a -> "str" + a` to `"str"::concat`. But only if `str` is provably non-null.
@@ -51,8 +55,7 @@ import javax.lang.model.element.Name;
 // Palantir's `LambdaMethodReference` check seems to suffer a similar issue at this time.
 // XXX: Expressions of the form `i -> SomeType.class.isInstance(i)` are not replaced; fix that using
 // a suitable generalization.
-// XXX: Consider folding the `IsInstanceLambdaUsage` check of the `error-prone-contrib` module into
-// this class.
+// XXX: Consider folding the `IsInstanceLambdaUsage` check into this class.
 @AutoService(BugChecker.class)
 @BugPattern(
     summary = "Prefer method references over lambda expressions",
@@ -83,19 +86,22 @@ public final class MethodReferenceUsage extends BugChecker implements LambdaExpr
         .orElse(Description.NO_MATCH);
   }
 
-  // XXX: Use switch pattern matching once the targeted JDK supports this.
   private static Optional<SuggestedFix.Builder> constructMethodRef(
       LambdaExpressionTree lambdaExpr, Tree subTree) {
-    return switch (subTree.getKind()) {
-      case BLOCK -> constructMethodRef(lambdaExpr, (BlockTree) subTree);
-      case EXPRESSION_STATEMENT ->
-          constructMethodRef(lambdaExpr, ((ExpressionStatementTree) subTree).getExpression());
-      case METHOD_INVOCATION -> constructMethodRef(lambdaExpr, (MethodInvocationTree) subTree);
-      case PARENTHESIZED ->
-          constructMethodRef(lambdaExpr, ((ParenthesizedTree) subTree).getExpression());
-      case RETURN -> constructMethodRef(lambdaExpr, ((ReturnTree) subTree).getExpression());
-      default -> Optional.empty();
-    };
+    switch (subTree.getKind()) {
+      case BLOCK:
+        return constructMethodRef(lambdaExpr, (BlockTree) subTree);
+      case EXPRESSION_STATEMENT:
+        return constructMethodRef(lambdaExpr, ((ExpressionStatementTree) subTree).getExpression());
+      case METHOD_INVOCATION:
+        return constructMethodRef(lambdaExpr, (MethodInvocationTree) subTree);
+      case PARENTHESIZED:
+        return constructMethodRef(lambdaExpr, ((ParenthesizedTree) subTree).getExpression());
+      case RETURN:
+        return constructMethodRef(lambdaExpr, ((ReturnTree) subTree).getExpression());
+      default:
+        return Optional.empty();
+    }
   }
 
   private static Optional<SuggestedFix.Builder> constructMethodRef(
@@ -113,35 +119,33 @@ public final class MethodReferenceUsage extends BugChecker implements LambdaExpr
         .flatMap(expectedInstance -> constructMethodRef(lambdaExpr, subTree, expectedInstance));
   }
 
-  // XXX: Review whether to use switch pattern matching once the targeted JDK supports this.
+  @SuppressWarnings(
+      "java:S1151" /* Extracting `IDENTIFIER` case block to separate method does not improve readability. */)
   private static Optional<SuggestedFix.Builder> constructMethodRef(
       LambdaExpressionTree lambdaExpr,
       MethodInvocationTree subTree,
       Optional<Name> expectedInstance) {
     ExpressionTree methodSelect = subTree.getMethodSelect();
-
-    if (methodSelect instanceof IdentifierTree) {
-      if (expectedInstance.isPresent()) {
-        /* Direct method call; there is no matching "implicit parameter". */
-        return Optional.empty();
-      }
-
-      Symbol sym = ASTHelpers.getSymbol(methodSelect);
-      return ASTHelpers.isStatic(sym)
-          ? constructFix(lambdaExpr, sym.owner, methodSelect)
-          : constructFix(lambdaExpr, "this", methodSelect);
+    switch (methodSelect.getKind()) {
+      case IDENTIFIER:
+        if (expectedInstance.isPresent()) {
+          /* Direct method call; there is no matching "implicit parameter". */
+          return Optional.empty();
+        }
+        Symbol sym = ASTHelpers.getSymbol(methodSelect);
+        return ASTHelpers.isStatic(sym)
+            ? constructFix(lambdaExpr, sym.owner, methodSelect)
+            : constructFix(lambdaExpr, "this", methodSelect);
+      case MEMBER_SELECT:
+        return constructMethodRef(lambdaExpr, (MemberSelectTree) methodSelect, expectedInstance);
+      default:
+        throw new VerifyException("Unexpected type of expression: " + methodSelect.getKind());
     }
-
-    if (methodSelect instanceof MemberSelectTree memberSelect) {
-      return constructMethodRef(lambdaExpr, memberSelect, expectedInstance);
-    }
-
-    throw new VerifyException("Unexpected type of expression: " + methodSelect.getKind());
   }
 
   private static Optional<SuggestedFix.Builder> constructMethodRef(
       LambdaExpressionTree lambdaExpr, MemberSelectTree subTree, Optional<Name> expectedInstance) {
-    if (!(subTree.getExpression() instanceof IdentifierTree identifier)) {
+    if (subTree.getExpression().getKind() != Kind.IDENTIFIER) {
       // XXX: Could be parenthesized. Handle. Also in other classes.
       /*
        * Only suggest a replacement if the method select's expression provably doesn't have
@@ -150,12 +154,12 @@ public final class MethodReferenceUsage extends BugChecker implements LambdaExpr
       return Optional.empty();
     }
 
-    Name lhs = identifier.getName();
+    Name lhs = ((IdentifierTree) subTree.getExpression()).getName();
     if (expectedInstance.isEmpty()) {
       return constructFix(lambdaExpr, lhs, subTree.getIdentifier());
     }
 
-    Type lhsType = ASTHelpers.getType(identifier);
+    Type lhsType = ASTHelpers.getType(subTree.getExpression());
     if (lhsType == null || !expectedInstance.orElseThrow().equals(lhs)) {
       return Optional.empty();
     }
@@ -180,13 +184,18 @@ public final class MethodReferenceUsage extends BugChecker implements LambdaExpr
 
     for (int i = 0; i < args.size(); i++) {
       ExpressionTree arg = args.get(i);
-      if (!(arg instanceof IdentifierTree identifier)
-          || !identifier.getName().equals(expectedArguments.get(i + diff))) {
+      if (arg.getKind() != Kind.IDENTIFIER
+          || !((IdentifierTree) arg).getName().equals(expectedArguments.get(i + diff))) {
         return Optional.empty();
       }
     }
 
-    return Optional.of(diff == 0 ? Optional.empty() : Optional.of(expectedArguments.get(0)));
+    // XXX: These type hints shouldn't be necessary; see
+    // https://github.com/typetools/checker-framework/issues/4007.
+    return Optional.of(
+        diff == 0
+            ? Optional.<@NonNull Name>empty()
+            : Optional.<@NonNull Name>of(expectedArguments.get(0)));
   }
 
   private static ImmutableList<Name> getVariables(LambdaExpressionTree tree) {

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/MockitoMockClassReference.java

@@ -9,7 +9,7 @@ import static com.google.errorprone.matchers.Matchers.isSameType;
 import static com.google.errorprone.matchers.Matchers.isVariable;
 import static com.google.errorprone.matchers.Matchers.not;
 import static com.google.errorprone.matchers.Matchers.staticMethod;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.errorprone.BugPattern;
@@ -25,7 +25,7 @@ import com.sun.source.tree.MethodInvocationTree;
 import com.sun.source.tree.Tree;
 import com.sun.source.tree.VariableTree;
 import java.util.List;
-import tech.picnic.errorprone.utils.MoreASTHelpers;
+import tech.picnic.errorprone.bugpatterns.util.MoreASTHelpers;
 
 /**
  * A {@link BugChecker} that flags the use of {@link org.mockito.Mockito#mock(Class)} and {@link
@@ -67,19 +67,20 @@ public final class MockitoMockClassReference extends BugChecker
     return describeMatch(tree, SuggestedFixes.removeElement(arguments.get(0), arguments, state));
   }
 
-  // XXX: Use switch pattern matching once the targeted JDK supports this.
   private static boolean isTypeDerivableFromContext(MethodInvocationTree tree, VisitorState state) {
     Tree parent = state.getPath().getParentPath().getLeaf();
-    return switch (parent.getKind()) {
-      case VARIABLE ->
-          !ASTHelpers.hasImplicitType((VariableTree) parent, state)
-              && MoreASTHelpers.areSameType(tree, parent, state);
-      case ASSIGNMENT -> MoreASTHelpers.areSameType(tree, parent, state);
-      case RETURN ->
-          MoreASTHelpers.findMethodExitedOnReturn(state)
-              .filter(m -> MoreASTHelpers.areSameType(tree, m.getReturnType(), state))
-              .isPresent();
-      default -> false;
-    };
+    switch (parent.getKind()) {
+      case VARIABLE:
+        return !ASTHelpers.hasImplicitType((VariableTree) parent, state)
+            && MoreASTHelpers.areSameType(tree, parent, state);
+      case ASSIGNMENT:
+        return MoreASTHelpers.areSameType(tree, parent, state);
+      case RETURN:
+        return MoreASTHelpers.findMethodExitedOnReturn(state)
+            .filter(m -> MoreASTHelpers.areSameType(tree, m.getReturnType(), state))
+            .isPresent();
+      default:
+        return false;
+    }
   }
 }

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/MockitoStubbing.java

@@ -4,7 +4,7 @@ import static com.google.errorprone.BugPattern.LinkType.CUSTOM;
 import static com.google.errorprone.BugPattern.SeverityLevel.SUGGESTION;
 import static com.google.errorprone.BugPattern.StandardTags.SIMPLIFICATION;
 import static com.google.errorprone.matchers.Matchers.staticMethod;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.common.collect.Iterables;
@@ -18,7 +18,7 @@ import com.google.errorprone.matchers.Matcher;
 import com.sun.source.tree.ExpressionTree;
 import com.sun.source.tree.MethodInvocationTree;
 import java.util.List;
-import tech.picnic.errorprone.utils.SourceCode;
+import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 
 /**
  * A {@link BugChecker} that flags method invocations for which all arguments are wrapped using

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/MongoDBTextFilterUsage.java

@@ -4,7 +4,7 @@ import static com.google.errorprone.BugPattern.LinkType.CUSTOM;
 import static com.google.errorprone.BugPattern.SeverityLevel.SUGGESTION;
 import static com.google.errorprone.BugPattern.StandardTags.PERFORMANCE;
 import static com.google.errorprone.matchers.method.MethodMatchers.staticMethod;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.errorprone.BugPattern;
@@ -24,9 +24,7 @@ import com.sun.source.tree.MethodInvocationTree;
 @AutoService(BugChecker.class)
 @BugPattern(
     summary =
-        """
-        Avoid MongoDB's `$text` filter operator, as it can trigger heavy queries and even cause \
-        the server to run out of memory""",
+        "Avoid MongoDB's `$text` filter operator, as it can trigger heavy queries and even cause the server to run out of memory",
     link = BUG_PATTERNS_BASE_URL + "MongoDBTextFilterUsage",
     linkType = CUSTOM,
     severity = SUGGESTION,

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/NestedOptionals.java

@@ -3,11 +3,11 @@ package tech.picnic.errorprone.bugpatterns;
 import static com.google.errorprone.BugPattern.LinkType.CUSTOM;
 import static com.google.errorprone.BugPattern.SeverityLevel.WARNING;
 import static com.google.errorprone.BugPattern.StandardTags.FRAGILE_CODE;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
-import static tech.picnic.errorprone.utils.MoreMatchers.isSubTypeOf;
-import static tech.picnic.errorprone.utils.MoreTypes.generic;
-import static tech.picnic.errorprone.utils.MoreTypes.raw;
-import static tech.picnic.errorprone.utils.MoreTypes.subOf;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.MoreMatchers.isSubTypeOf;
+import static tech.picnic.errorprone.bugpatterns.util.MoreTypes.generic;
+import static tech.picnic.errorprone.bugpatterns.util.MoreTypes.raw;
+import static tech.picnic.errorprone.bugpatterns.util.MoreTypes.subOf;
 
 import com.google.auto.service.AutoService;
 import com.google.errorprone.BugPattern;

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/NestedPublishers.java

@@ -6,13 +6,13 @@ import static com.google.errorprone.BugPattern.StandardTags.FRAGILE_CODE;
 import static com.google.errorprone.matchers.Matchers.typePredicateMatcher;
 import static com.google.errorprone.predicates.TypePredicates.allOf;
 import static com.google.errorprone.predicates.TypePredicates.not;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
-import static tech.picnic.errorprone.utils.MoreTypePredicates.hasTypeParameter;
-import static tech.picnic.errorprone.utils.MoreTypePredicates.isSubTypeOf;
-import static tech.picnic.errorprone.utils.MoreTypes.generic;
-import static tech.picnic.errorprone.utils.MoreTypes.raw;
-import static tech.picnic.errorprone.utils.MoreTypes.subOf;
-import static tech.picnic.errorprone.utils.MoreTypes.type;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.MoreTypePredicates.hasTypeParameter;
+import static tech.picnic.errorprone.bugpatterns.util.MoreTypePredicates.isSubTypeOf;
+import static tech.picnic.errorprone.bugpatterns.util.MoreTypes.generic;
+import static tech.picnic.errorprone.bugpatterns.util.MoreTypes.raw;
+import static tech.picnic.errorprone.bugpatterns.util.MoreTypes.subOf;
+import static tech.picnic.errorprone.bugpatterns.util.MoreTypes.type;
 
 import com.google.auto.service.AutoService;
 import com.google.errorprone.BugPattern;
@@ -34,9 +34,8 @@ import com.sun.tools.javac.code.Type;
 @AutoService(BugChecker.class)
 @BugPattern(
     summary =
-        """
-        Avoid `Publisher`s that emit other `Publishers`s; the resultant code is hard to reason \
-        about""",
+        "Avoid `Publisher`s that emit other `Publishers`s; "
+            + "the resultant code is hard to reason about",
     link = BUG_PATTERNS_BASE_URL + "NestedPublishers",
     linkType = CUSTOM,
     severity = WARNING,

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/NonEmptyMono.java

@@ -5,7 +5,7 @@ import static com.google.errorprone.BugPattern.SeverityLevel.WARNING;
 import static com.google.errorprone.BugPattern.StandardTags.SIMPLIFICATION;
 import static com.google.errorprone.matchers.Matchers.anyOf;
 import static com.google.errorprone.matchers.Matchers.instanceMethod;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.errorprone.BugPattern;
@@ -20,7 +20,7 @@ import com.sun.source.tree.ExpressionTree;
 import com.sun.source.tree.MethodInvocationTree;
 import java.util.function.BiFunction;
 import reactor.core.publisher.Mono;
-import tech.picnic.errorprone.utils.SourceCode;
+import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 
 /**
  * A {@link BugChecker} that flags {@link Mono} operations that are known to be vacuous, given that

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/NonStaticImport.java

@@ -4,7 +4,7 @@ import static com.google.errorprone.BugPattern.LinkType.CUSTOM;
 import static com.google.errorprone.BugPattern.SeverityLevel.SUGGESTION;
 import static com.google.errorprone.BugPattern.StandardTags.STYLE;
 import static tech.picnic.errorprone.bugpatterns.StaticImport.STATIC_IMPORT_CANDIDATE_MEMBERS;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.auto.value.AutoValue;
@@ -33,10 +33,9 @@ import java.time.Clock;
 import java.time.ZoneOffset;
 import java.util.Collections;
 import java.util.Locale;
-import java.util.Optional;
 import java.util.regex.Pattern;
 import org.jspecify.annotations.Nullable;
-import tech.picnic.errorprone.utils.SourceCode;
+import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 
 /**
  * A {@link BugChecker} that flags static imports of type members that should *not* be statically
@@ -72,9 +71,7 @@ public final class NonStaticImport extends BugChecker implements CompilationUnit
           Strings.class.getCanonicalName(),
           VisitorState.class.getCanonicalName(),
           ZoneOffset.class.getCanonicalName(),
-          "com.google.errorprone.BugCheckerRefactoringTestHelper.TestMode",
-          "reactor.core.publisher.Flux",
-          "reactor.core.publisher.Mono");
+          "com.google.errorprone.BugCheckerRefactoringTestHelper.TestMode");
 
   /**
    * Type members that should never be statically imported.
@@ -106,7 +103,6 @@ public final class NonStaticImport extends BugChecker implements CompilationUnit
               "sort",
               "swap")
           .put(Locale.class.getCanonicalName(), "ROOT")
-          .put(Optional.class.getCanonicalName(), "empty")
           .putAll(Pattern.class.getCanonicalName(), "compile", "matches", "quote")
           .put(Predicates.class.getCanonicalName(), "contains")
           .put("org.springframework.http.MediaType", "ALL")
@@ -129,6 +125,7 @@ public final class NonStaticImport extends BugChecker implements CompilationUnit
           "builder",
           "copyOf",
           "create",
+          "empty",
           "from",
           "getDefaultInstance",
           "INSTANCE",
@@ -139,8 +136,10 @@ public final class NonStaticImport extends BugChecker implements CompilationUnit
           "newBuilder",
           "newInstance",
           "of",
+          "ONE",
           "parse",
-          "valueOf");
+          "valueOf",
+          "ZERO");
 
   /** Instantiates a new {@link NonStaticImport} instance. */
   public NonStaticImport() {}
@@ -169,9 +168,10 @@ public final class NonStaticImport extends BugChecker implements CompilationUnit
         ImmutableTable.builder();
     for (ImportTree importTree : tree.getImports()) {
       Tree qualifiedIdentifier = importTree.getQualifiedIdentifier();
-      if (importTree.isStatic() && qualifiedIdentifier instanceof MemberSelectTree memberSelect) {
-        String type = SourceCode.treeToString(memberSelect.getExpression(), state);
-        String member = memberSelect.getIdentifier().toString();
+      if (importTree.isStatic() && qualifiedIdentifier instanceof MemberSelectTree) {
+        MemberSelectTree memberSelectTree = (MemberSelectTree) qualifiedIdentifier;
+        String type = SourceCode.treeToString(memberSelectTree.getExpression(), state);
+        String member = memberSelectTree.getIdentifier().toString();
         if (shouldNotBeStaticallyImported(type, member)) {
           imports.put(
               type,
@@ -210,7 +210,7 @@ public final class NonStaticImport extends BugChecker implements CompilationUnit
           }
         }
 
-        return super.visitIdentifier(node, null);
+        return super.visitIdentifier(node, unused);
       }
     }.scan(tree, null);
   }

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/OptionalOrElse.java

@@ -1,135 +0,0 @@
-package tech.picnic.errorprone.bugpatterns;
-
-import static com.google.errorprone.BugPattern.LinkType.NONE;
-import static com.google.errorprone.BugPattern.SeverityLevel.WARNING;
-import static com.google.errorprone.BugPattern.StandardTags.PERFORMANCE;
-import static com.google.errorprone.matchers.Matchers.instanceMethod;
-import static com.google.errorprone.matchers.Matchers.staticMethod;
-import static java.util.stream.Collectors.joining;
-
-import com.google.auto.service.AutoService;
-import com.google.common.collect.Iterables;
-import com.google.errorprone.BugPattern;
-import com.google.errorprone.VisitorState;
-import com.google.errorprone.bugpatterns.BugChecker;
-import com.google.errorprone.bugpatterns.BugChecker.MethodInvocationTreeMatcher;
-import com.google.errorprone.fixes.SuggestedFix;
-import com.google.errorprone.fixes.SuggestedFixes;
-import com.google.errorprone.matchers.Description;
-import com.google.errorprone.matchers.Matcher;
-import com.google.errorprone.refaster.Refaster;
-import com.google.errorprone.util.ASTHelpers;
-import com.sun.source.tree.ExpressionTree;
-import com.sun.source.tree.IdentifierTree;
-import com.sun.source.tree.LiteralTree;
-import com.sun.source.tree.MemberSelectTree;
-import com.sun.source.tree.MethodInvocationTree;
-import java.util.Optional;
-import java.util.function.Supplier;
-import tech.picnic.errorprone.utils.SourceCode;
-
-/**
- * A {@link BugChecker} that flags arguments to {@link Optional#orElse(Object)} that should be
- * deferred using {@link Optional#orElseGet(Supplier)}.
- *
- * <p>The suggested fix assumes that the argument to {@code orElse} does not have side effects. If
- * it does, the suggested fix changes the program's semantics. Such fragile code must instead be
- * refactored such that the side-effectful code does not appear accidental.
- */
-// XXX: Consider also implementing the inverse, in which `.orElseGet(() -> someConstant)` is
-// flagged.
-// XXX: Once the `MethodReferenceUsageCheck` becomes generally usable, consider leaving the method
-// reference cleanup to that check, and express the remainder of the logic in this class using a
-// Refaster template, i.c.w. a `@Matches` constraint that implements the `requiresComputation`
-// logic.
-@AutoService(BugChecker.class)
-@BugPattern(
-    summary =
-        """
-        Prefer `Optional#orElseGet` over `Optional#orElse` if the fallback requires additional \
-        computation""",
-    linkType = NONE,
-    severity = WARNING,
-    tags = PERFORMANCE)
-public final class OptionalOrElse extends BugChecker implements MethodInvocationTreeMatcher {
-  private static final long serialVersionUID = 1L;
-  private static final Matcher<ExpressionTree> OPTIONAL_OR_ELSE_METHOD =
-      instanceMethod().onExactClass(Optional.class.getCanonicalName()).namedAnyOf("orElse");
-  // XXX: Also exclude invocations of `@Placeholder`-annotated methods.
-  private static final Matcher<ExpressionTree> REFASTER_METHOD =
-      staticMethod().onClass(Refaster.class.getCanonicalName());
-
-  /** Instantiates a new {@link OptionalOrElse} instance. */
-  public OptionalOrElse() {}
-
-  @Override
-  public Description matchMethodInvocation(MethodInvocationTree tree, VisitorState state) {
-    if (!OPTIONAL_OR_ELSE_METHOD.matches(tree, state)) {
-      return Description.NO_MATCH;
-    }
-
-    ExpressionTree argument = Iterables.getOnlyElement(tree.getArguments());
-    if (!requiresComputation(argument) || REFASTER_METHOD.matches(argument, state)) {
-      return Description.NO_MATCH;
-    }
-
-    /*
-     * We have a match. Construct the method reference or lambda expression to be passed to the
-     * replacement `#orElseGet` invocation.
-     */
-    String newArgument =
-        tryMethodReferenceConversion(argument, state)
-            .orElseGet(() -> "() -> " + SourceCode.treeToString(argument, state));
-
-    /* Construct the suggested fix, replacing the method invocation and its argument. */
-    SuggestedFix fix =
-        SuggestedFix.builder()
-            .merge(SuggestedFixes.renameMethodInvocation(tree, "orElseGet", state))
-            .replace(argument, newArgument)
-            .build();
-
-    return describeMatch(tree, fix);
-  }
-
-  /**
-   * Tells whether the given expression contains anything other than a literal or a (possibly
-   * dereferenced) variable or constant.
-   */
-  private static boolean requiresComputation(ExpressionTree tree) {
-    return !(tree instanceof IdentifierTree
-        || tree instanceof LiteralTree
-        || (tree instanceof MemberSelectTree memberSelect
-            && !requiresComputation(memberSelect.getExpression()))
-        || ASTHelpers.constValue(tree) != null);
-  }
-
-  /** Returns the nullary method reference matching the given expression, if any. */
-  private static Optional<String> tryMethodReferenceConversion(
-      ExpressionTree tree, VisitorState state) {
-    if (!(tree instanceof MethodInvocationTree methodInvocation)) {
-      return Optional.empty();
-    }
-
-    if (!methodInvocation.getArguments().isEmpty()) {
-      return Optional.empty();
-    }
-
-    if (!(methodInvocation.getMethodSelect() instanceof MemberSelectTree memberSelect)) {
-      return Optional.empty();
-    }
-
-    if (requiresComputation(memberSelect.getExpression())) {
-      return Optional.empty();
-    }
-
-    return Optional.of(
-        SourceCode.treeToString(memberSelect.getExpression(), state)
-            + "::"
-            + (methodInvocation.getTypeArguments().isEmpty()
-                ? ""
-                : methodInvocation.getTypeArguments().stream()
-                    .map(arg -> SourceCode.treeToString(arg, state))
-                    .collect(joining(",", "<", ">")))
-            + memberSelect.getIdentifier());
-  }
-}

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/PrimitiveComparison.java

@@ -7,7 +7,7 @@ import static com.google.errorprone.matchers.Matchers.anyOf;
 import static com.google.errorprone.matchers.method.MethodMatchers.instanceMethod;
 import static com.google.errorprone.matchers.method.MethodMatchers.staticMethod;
 import static java.util.stream.Collectors.joining;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.common.base.VerifyException;
@@ -22,7 +22,6 @@ import com.google.errorprone.matchers.Description;
 import com.google.errorprone.matchers.Matcher;
 import com.google.errorprone.util.ASTHelpers;
 import com.sun.source.tree.ExpressionTree;
-import com.sun.source.tree.IdentifierTree;
 import com.sun.source.tree.LambdaExpressionTree;
 import com.sun.source.tree.MemberSelectTree;
 import com.sun.source.tree.MethodInvocationTree;
@@ -34,7 +33,7 @@ import java.util.Comparator;
 import java.util.Optional;
 import java.util.function.Function;
 import java.util.stream.Stream;
-import tech.picnic.errorprone.utils.SourceCode;
+import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 
 /**
  * A {@link BugChecker} that flags {@code Comparator#comparing*} invocations that can be replaced
@@ -45,9 +44,8 @@ import tech.picnic.errorprone.utils.SourceCode;
 @AutoService(BugChecker.class)
 @BugPattern(
     summary =
-        """
-        Ensure invocations of `Comparator#comparing{,Double,Int,Long}` match the return type of \
-        the provided function""",
+        "Ensure invocations of `Comparator#comparing{,Double,Int,Long}` match the return type"
+            + " of the provided function",
     link = BUG_PATTERNS_BASE_URL + "PrimitiveComparison",
     linkType = CUSTOM,
     severity = WARNING,
@@ -149,44 +147,38 @@ public final class PrimitiveComparison extends BugChecker implements MethodInvoc
     return isStatic ? "comparing" : "thenComparing";
   }
 
-  // XXX: Use switch pattern matching once the targeted JDK supports this.
   private static Optional<Type> getPotentiallyBoxedReturnType(ExpressionTree tree) {
-    if (tree instanceof LambdaExpressionTree lambdaExpression) {
-      /* Return the lambda expression's actual return type. */
-      return Optional.ofNullable(ASTHelpers.getType(lambdaExpression.getBody()));
+    switch (tree.getKind()) {
+      case LAMBDA_EXPRESSION:
+        /* Return the lambda expression's actual return type. */
+        return Optional.ofNullable(ASTHelpers.getType(((LambdaExpressionTree) tree).getBody()));
+      case MEMBER_REFERENCE:
+        /* Return the method's declared return type. */
+        // XXX: Very fragile. Do better.
+        Type subType2 = ((JCMemberReference) tree).referentType;
+        return Optional.of(subType2.getReturnType());
+      default:
+        /* This appears to be a genuine `{,ToInt,ToLong,ToDouble}Function`. */
+        return Optional.empty();
     }
-
-    // XXX: The match against a concrete type and reference to one of its fields is fragile. Do
-    // better.
-    if (tree instanceof JCMemberReference memberReference) {
-      /* Return the method's declared return type. */
-      Type subType = memberReference.referentType;
-      return Optional.of(subType.getReturnType());
-    }
-
-    /* This appears to be a genuine `{,ToInt,ToLong,ToDouble}Function`. */
-    return Optional.empty();
   }
 
-  // XXX: Use switch pattern matching once the targeted JDK supports this.
   private static Fix suggestFix(
       MethodInvocationTree tree, String preferredMethodName, VisitorState state) {
     ExpressionTree expr = tree.getMethodSelect();
-
-    if (expr instanceof IdentifierTree) {
-      SuggestedFix.Builder fix = SuggestedFix.builder();
-      String replacement =
-          SuggestedFixes.qualifyStaticImport(
-              Comparator.class.getCanonicalName() + '.' + preferredMethodName, fix, state);
-      return fix.replace(expr, replacement).build();
+    switch (expr.getKind()) {
+      case IDENTIFIER:
+        SuggestedFix.Builder fix = SuggestedFix.builder();
+        String replacement =
+            SuggestedFixes.qualifyStaticImport(
+                Comparator.class.getCanonicalName() + '.' + preferredMethodName, fix, state);
+        return fix.replace(expr, replacement).build();
+      case MEMBER_SELECT:
+        MemberSelectTree ms = (MemberSelectTree) tree.getMethodSelect();
+        return SuggestedFix.replace(
+            ms, SourceCode.treeToString(ms.getExpression(), state) + '.' + preferredMethodName);
+      default:
+        throw new VerifyException("Unexpected type of expression: " + expr.getKind());
     }
-
-    if (expr instanceof MemberSelectTree memberSelect) {
-      return SuggestedFix.replace(
-          memberSelect,
-          SourceCode.treeToString(memberSelect.getExpression(), state) + '.' + preferredMethodName);
-    }
-
-    throw new VerifyException("Unexpected type of expression: " + expr.getKind());
   }
 }

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/RedundantStringConversion.java

@@ -15,7 +15,7 @@ import static com.google.errorprone.matchers.Matchers.isSubtypeOf;
 import static com.google.errorprone.matchers.Matchers.not;
 import static com.google.errorprone.matchers.method.MethodMatchers.instanceMethod;
 import static com.google.errorprone.matchers.method.MethodMatchers.staticMethod;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.common.base.Preconditions;
@@ -53,9 +53,9 @@ import java.util.Objects;
 import java.util.Optional;
 import java.util.stream.Stream;
 import javax.inject.Inject;
-import tech.picnic.errorprone.utils.Flags;
-import tech.picnic.errorprone.utils.MethodMatcherFactory;
-import tech.picnic.errorprone.utils.SourceCode;
+import tech.picnic.errorprone.bugpatterns.util.Flags;
+import tech.picnic.errorprone.bugpatterns.util.MethodMatcherFactory;
+import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 
 /** A {@link BugChecker} that flags redundant explicit string conversions. */
 @AutoService(BugChecker.class)
@@ -331,32 +331,36 @@ public final class RedundantStringConversion extends BugChecker
   }
 
   private Optional<ExpressionTree> trySimplify(ExpressionTree tree, VisitorState state) {
-    if (!(tree instanceof MethodInvocationTree methodInvocation)) {
+    if (tree.getKind() != Kind.METHOD_INVOCATION) {
       return Optional.empty();
     }
 
+    MethodInvocationTree methodInvocation = (MethodInvocationTree) tree;
     if (!conversionMethodMatcher.matches(methodInvocation, state)) {
       return Optional.empty();
     }
 
-    return switch (methodInvocation.getArguments().size()) {
-      case 0 -> trySimplifyNullaryMethod(methodInvocation, state);
-      case 1 -> trySimplifyUnaryMethod(methodInvocation, state);
-      default ->
-          throw new IllegalStateException(
-              "Cannot simplify method call with two or more arguments: "
-                  + SourceCode.treeToString(tree, state));
-    };
+    switch (methodInvocation.getArguments().size()) {
+      case 0:
+        return trySimplifyNullaryMethod(methodInvocation, state);
+      case 1:
+        return trySimplifyUnaryMethod(methodInvocation, state);
+      default:
+        throw new IllegalStateException(
+            "Cannot simplify method call with two or more arguments: "
+                + SourceCode.treeToString(tree, state));
+    }
   }
 
   private static Optional<ExpressionTree> trySimplifyNullaryMethod(
       MethodInvocationTree methodInvocation, VisitorState state) {
-    if (!instanceMethod().matches(methodInvocation, state)
-        || !(methodInvocation.getMethodSelect() instanceof MemberSelectTree memberSelect)) {
+    if (!instanceMethod().matches(methodInvocation, state)) {
       return Optional.empty();
     }
 
-    return Optional.of(memberSelect.getExpression())
+    return Optional.of(methodInvocation.getMethodSelect())
+        .filter(methodSelect -> methodSelect.getKind() == Kind.MEMBER_SELECT)
+        .map(methodSelect -> ((MemberSelectTree) methodSelect).getExpression())
         .filter(expr -> !"super".equals(SourceCode.treeToString(expr, state)));
   }
 

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/RefasterAnyOfUsage.java

@@ -1,10 +1,10 @@
-package tech.picnic.errorprone.guidelines.bugpatterns;
+package tech.picnic.errorprone.bugpatterns;
 
 import static com.google.errorprone.BugPattern.LinkType.CUSTOM;
 import static com.google.errorprone.BugPattern.SeverityLevel.SUGGESTION;
 import static com.google.errorprone.BugPattern.StandardTags.SIMPLIFICATION;
 import static com.google.errorprone.matchers.method.MethodMatchers.staticMethod;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.errorprone.BugPattern;
@@ -17,7 +17,7 @@ import com.google.errorprone.matchers.Matcher;
 import com.google.errorprone.refaster.Refaster;
 import com.sun.source.tree.ExpressionTree;
 import com.sun.source.tree.MethodInvocationTree;
-import tech.picnic.errorprone.utils.SourceCode;
+import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 
 /**
  * A {@link BugChecker} that flags unnecessary {@link Refaster#anyOf(Object[])} usages.
@@ -42,18 +42,21 @@ public final class RefasterAnyOfUsage extends BugChecker implements MethodInvoca
 
   @Override
   public Description matchMethodInvocation(MethodInvocationTree tree, VisitorState state) {
-    int argumentCount = tree.getArguments().size();
-    if (argumentCount > 1 || !REFASTER_ANY_OF.matches(tree, state)) {
-      return Description.NO_MATCH;
+    if (REFASTER_ANY_OF.matches(tree, state)) {
+      switch (tree.getArguments().size()) {
+        case 0:
+          // We can't safely fix this case; dropping the expression may produce non-compilable code.
+          return describeMatch(tree);
+        case 1:
+          return describeMatch(
+              tree,
+              SuggestedFix.replace(
+                  tree, SourceCode.treeToString(tree.getArguments().get(0), state)));
+        default:
+          /* Handled below. */
+      }
     }
 
-    if (argumentCount == 0) {
-      /* We can't safely fix this case; dropping the expression may produce non-compilable code. */
-      return describeMatch(tree);
-    }
-
-    return describeMatch(
-        tree,
-        SuggestedFix.replace(tree, SourceCode.treeToString(tree.getArguments().get(0), state)));
+    return Description.NO_MATCH;
   }
 }

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/RefasterRuleModifiers.java

@@ -1,11 +1,11 @@
-package tech.picnic.errorprone.guidelines.bugpatterns;
+package tech.picnic.errorprone.bugpatterns;
 
 import static com.google.errorprone.BugPattern.LinkType.CUSTOM;
 import static com.google.errorprone.BugPattern.SeverityLevel.SUGGESTION;
 import static com.google.errorprone.BugPattern.StandardTags.STYLE;
 import static com.google.errorprone.matchers.Matchers.anyOf;
 import static com.google.errorprone.matchers.Matchers.hasAnnotation;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.errorprone.BugPattern;

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/RequestMappingAnnotation.java

@@ -11,7 +11,7 @@ import static com.google.errorprone.matchers.Matchers.isSameType;
 import static com.google.errorprone.matchers.Matchers.isType;
 import static com.google.errorprone.matchers.Matchers.methodHasParameters;
 import static com.google.errorprone.matchers.Matchers.not;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.errorprone.BugPattern;
@@ -73,9 +73,7 @@ public final class RequestMappingAnnotation extends BugChecker implements Method
                           isType(ANN_PACKAGE_PREFIX + "RequestBody"),
                           isType(ANN_PACKAGE_PREFIX + "RequestHeader"),
                           isType(ANN_PACKAGE_PREFIX + "RequestParam"),
-                          isType(ANN_PACKAGE_PREFIX + "RequestPart"),
-                          isType(
-                              "org.springframework.security.core.annotation.CurrentSecurityContext"))),
+                          isType(ANN_PACKAGE_PREFIX + "RequestPart"))),
                   isSameType(InputStream.class.getCanonicalName()),
                   isSameType(Locale.class.getCanonicalName()),
                   isSameType(TimeZone.class.getCanonicalName()),
@@ -105,10 +103,9 @@ public final class RequestMappingAnnotation extends BugChecker implements Method
             && LACKS_PARAMETER_ANNOTATION.matches(tree, state)
         ? buildDescription(tree)
             .setMessage(
-                """
-                Not all parameters of this request mapping method are annotated; this may be a \
-                mistake. If the unannotated parameters represent query string parameters, annotate \
-                them with `@RequestParam`.""")
+                "Not all parameters of this request mapping method are annotated; this may be a "
+                    + "mistake. If the unannotated parameters represent query string parameters, "
+                    + "annotate them with `@RequestParam`.")
             .build()
         : Description.NO_MATCH;
   }

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/RequestParamType.java

@@ -11,7 +11,7 @@ import static com.google.errorprone.matchers.Matchers.anyOf;
 import static com.google.errorprone.matchers.Matchers.isSubtypeOf;
 import static com.google.errorprone.matchers.Matchers.isType;
 import static com.google.errorprone.matchers.Matchers.not;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.common.collect.ImmutableCollection;
@@ -28,15 +28,13 @@ import com.google.errorprone.suppliers.Suppliers;
 import com.sun.source.tree.Tree;
 import com.sun.source.tree.VariableTree;
 import javax.inject.Inject;
-import tech.picnic.errorprone.utils.Flags;
+import tech.picnic.errorprone.bugpatterns.util.Flags;
 
 /** A {@link BugChecker} that flags {@code @RequestParam} parameters with an unsupported type. */
 @AutoService(BugChecker.class)
 @BugPattern(
     summary =
-        """
-        By default, `@RequestParam` does not support `ImmutableCollection` and `ImmutableMap` \
-        subtypes""",
+        "By default, `@RequestParam` does not support `ImmutableCollection` and `ImmutableMap` subtypes",
     link = BUG_PATTERNS_BASE_URL + "RequestParamType",
     linkType = CUSTOM,
     severity = ERROR,

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/Slf4jLogStatement.java

@@ -6,7 +6,7 @@ import static com.google.errorprone.BugPattern.SeverityLevel.WARNING;
 import static com.google.errorprone.BugPattern.StandardTags.LIKELY_ERROR;
 import static com.google.errorprone.matchers.Matchers.isSubtypeOf;
 import static com.google.errorprone.matchers.method.MethodMatchers.instanceMethod;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.common.base.Splitter;
@@ -23,7 +23,7 @@ import com.sun.source.tree.MethodInvocationTree;
 import com.sun.source.tree.Tree.Kind;
 import java.util.List;
 import java.util.Optional;
-import tech.picnic.errorprone.utils.SourceCode;
+import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 
 /** A {@link BugChecker} that flags SLF4J usages that are likely to be in error. */
 // XXX: The special-casing of Throwable applies only to SLF4J 1.6.0+; see

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/SpringMvcAnnotation.java

@@ -1,11 +1,12 @@
 package tech.picnic.errorprone.bugpatterns;
 
+import static com.google.common.base.Verify.verify;
 import static com.google.errorprone.BugPattern.LinkType.CUSTOM;
 import static com.google.errorprone.BugPattern.SeverityLevel.SUGGESTION;
 import static com.google.errorprone.BugPattern.StandardTags.SIMPLIFICATION;
 import static java.util.function.Predicate.not;
 import static java.util.stream.Collectors.joining;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.common.base.VerifyException;
@@ -24,9 +25,10 @@ import com.sun.source.tree.AssignmentTree;
 import com.sun.source.tree.ExpressionTree;
 import com.sun.source.tree.MemberSelectTree;
 import com.sun.source.tree.NewArrayTree;
+import com.sun.source.tree.Tree.Kind;
 import java.util.Optional;
-import tech.picnic.errorprone.utils.AnnotationAttributeMatcher;
-import tech.picnic.errorprone.utils.SourceCode;
+import tech.picnic.errorprone.bugpatterns.util.AnnotationAttributeMatcher;
+import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 
 /**
  * A {@link BugChecker} that flags {@code @RequestMapping} annotations that can be written more
@@ -78,25 +80,31 @@ public final class SpringMvcAnnotation extends BugChecker implements AnnotationT
   }
 
   private static Optional<String> extractUniqueMethod(ExpressionTree arg, VisitorState state) {
-    if (!(arg instanceof AssignmentTree assignment)) {
-      throw new VerifyException("Annotation attribute is not an assignment:" + arg.getKind());
+    verify(
+        arg.getKind() == Kind.ASSIGNMENT,
+        "Annotation attribute is not an assignment: %s",
+        arg.getKind());
+
+    ExpressionTree expr = ((AssignmentTree) arg).getExpression();
+    if (expr.getKind() != Kind.NEW_ARRAY) {
+      return Optional.of(extractMethod(expr, state));
     }
 
-    ExpressionTree expr = assignment.getExpression();
-    return expr instanceof NewArrayTree newArray
-        ? Optional.of(newArray.getInitializers())
-            .filter(args -> args.size() == 1)
-            .map(args -> extractMethod(args.get(0), state))
-        : Optional.of(extractMethod(expr, state));
+    NewArrayTree newArray = (NewArrayTree) expr;
+    return Optional.of(newArray.getInitializers())
+        .filter(args -> args.size() == 1)
+        .map(args -> extractMethod(args.get(0), state));
   }
 
-  // XXX: Use switch pattern matching once the targeted JDK supports this.
   private static String extractMethod(ExpressionTree expr, VisitorState state) {
-    return switch (expr.getKind()) {
-      case IDENTIFIER -> SourceCode.treeToString(expr, state);
-      case MEMBER_SELECT -> ((MemberSelectTree) expr).getIdentifier().toString();
-      default -> throw new VerifyException("Unexpected type of expression: " + expr.getKind());
-    };
+    switch (expr.getKind()) {
+      case IDENTIFIER:
+        return SourceCode.treeToString(expr, state);
+      case MEMBER_SELECT:
+        return ((MemberSelectTree) expr).getIdentifier().toString();
+      default:
+        throw new VerifyException("Unexpected type of expression: " + expr.getKind());
+    }
   }
 
   private static Fix replaceAnnotation(

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/StaticImport.java

@@ -6,7 +6,7 @@ import static com.google.errorprone.BugPattern.StandardTags.STYLE;
 import static java.util.Objects.requireNonNull;
 import static tech.picnic.errorprone.bugpatterns.NonStaticImport.NON_STATIC_IMPORT_CANDIDATE_IDENTIFIERS;
 import static tech.picnic.errorprone.bugpatterns.NonStaticImport.NON_STATIC_IMPORT_CANDIDATE_MEMBERS;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.common.annotations.VisibleForTesting;
@@ -39,13 +39,11 @@ import com.google.errorprone.fixes.SuggestedFix;
 import com.google.errorprone.fixes.SuggestedFixes;
 import com.google.errorprone.matchers.Description;
 import com.google.errorprone.matchers.Matchers;
-import com.google.errorprone.predicates.TypePredicates;
 import com.google.errorprone.refaster.ImportPolicy;
 import com.google.errorprone.util.ASTHelpers;
 import com.sun.source.tree.MemberSelectTree;
 import com.sun.source.tree.MethodInvocationTree;
 import com.sun.source.tree.Tree;
-import com.sun.source.tree.Tree.Kind;
 import com.sun.tools.javac.code.Type;
 import java.nio.charset.StandardCharsets;
 import java.time.ZoneOffset;
@@ -102,7 +100,6 @@ public final class StaticImport extends BugChecker implements MemberSelectTreeMa
           Preconditions.class.getCanonicalName(),
           Predicates.class.getCanonicalName(),
           StandardCharsets.class.getCanonicalName(),
-          TypePredicates.class.getCanonicalName(),
           Verify.class.getCanonicalName(),
           "com.fasterxml.jackson.annotation.JsonCreator.Mode",
           "com.fasterxml.jackson.annotation.JsonFormat.Shape",
@@ -135,7 +132,7 @@ public final class StaticImport extends BugChecker implements MemberSelectTreeMa
           "org.springframework.http.MediaType",
           "org.testng.Assert",
           "reactor.function.TupleUtils",
-          "tech.picnic.errorprone.utils.MoreTypes");
+          "tech.picnic.errorprone.bugpatterns.util.MoreTypes");
 
   /**
    * Type members that should be statically imported.
@@ -212,10 +209,15 @@ public final class StaticImport extends BugChecker implements MemberSelectTreeMa
     Tree parentTree =
         requireNonNull(state.getPath().getParentPath(), "MemberSelectTree lacks enclosing node")
             .getLeaf();
-
-    return parentTree instanceof MethodInvocationTree methodInvocation
-        ? methodInvocation.getTypeArguments().isEmpty()
-        : (parentTree.getKind() != Kind.IMPORT && parentTree.getKind() != Kind.MEMBER_SELECT);
+    switch (parentTree.getKind()) {
+      case IMPORT:
+      case MEMBER_SELECT:
+        return false;
+      case METHOD_INVOCATION:
+        return ((MethodInvocationTree) parentTree).getTypeArguments().isEmpty();
+      default:
+        return true;
+    }
   }
 
   private static boolean isCandidate(MemberSelectTree tree) {

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/StringJoin.java

@@ -4,7 +4,7 @@ import static com.google.errorprone.BugPattern.LinkType.CUSTOM;
 import static com.google.errorprone.BugPattern.SeverityLevel.SUGGESTION;
 import static com.google.errorprone.BugPattern.StandardTags.SIMPLIFICATION;
 import static com.google.errorprone.matchers.method.MethodMatchers.staticMethod;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.common.base.Splitter;
@@ -28,7 +28,7 @@ import java.util.Formattable;
 import java.util.Iterator;
 import java.util.List;
 import org.jspecify.annotations.Nullable;
-import tech.picnic.errorprone.utils.SourceCode;
+import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 
 /**
  * A {@link BugChecker} that flags {@link String#format(String, Object...)} invocations which can be

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/TimeZoneUsage.java

@@ -10,7 +10,7 @@ import static com.google.errorprone.matchers.Matchers.instanceMethod;
 import static com.google.errorprone.matchers.Matchers.isSubtypeOf;
 import static com.google.errorprone.matchers.Matchers.not;
 import static com.google.errorprone.matchers.Matchers.staticMethod;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.errorprone.BugPattern;
@@ -34,9 +34,7 @@ import java.time.ZonedDateTime;
 @AutoService(BugChecker.class)
 @BugPattern(
     summary =
-        """
-        Derive the current time from an existing `Clock` Spring bean, and don't rely on a \
-        `Clock`'s time zone""",
+        "Derive the current time from an existing `Clock` Spring bean, and don't rely on a `Clock`'s time zone",
     link = BUG_PATTERNS_BASE_URL + "TimeZoneUsage",
     linkType = CUSTOM,
     severity = WARNING,

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/UnqualifiedSuggestedFixImport.java

@@ -1,10 +1,10 @@
-package tech.picnic.errorprone.guidelines.bugpatterns;
+package tech.picnic.errorprone.bugpatterns;
 
 import static com.google.errorprone.BugPattern.LinkType.CUSTOM;
 import static com.google.errorprone.BugPattern.SeverityLevel.WARNING;
 import static com.google.errorprone.BugPattern.StandardTags.FRAGILE_CODE;
 import static com.google.errorprone.matchers.Matchers.instanceMethod;
-import static tech.picnic.errorprone.utils.Documentation.BUG_PATTERNS_BASE_URL;
+import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.errorprone.BugPattern;
@@ -45,14 +45,16 @@ public final class UnqualifiedSuggestedFixImport extends BugChecker
       return Description.NO_MATCH;
     }
 
-    return switch (ASTHelpers.getSymbol(tree).getSimpleName().toString()) {
-      case "addImport" ->
-          createDescription(tree, "SuggestedFix.Builder#addImport", "SuggestedFixes#qualifyType");
-      case "addStaticImport" ->
-          createDescription(
-              tree, "SuggestedFix.Builder#addStaticImport", "SuggestedFixes#qualifyStaticImport");
-      default -> Description.NO_MATCH;
-    };
+    switch (ASTHelpers.getSymbol(tree).getSimpleName().toString()) {
+      case "addImport":
+        return createDescription(
+            tree, "SuggestedFix.Builder#addImport", "SuggestedFixes#qualifyType");
+      case "addStaticImport":
+        return createDescription(
+            tree, "SuggestedFix.Builder#addStaticImport", "SuggestedFixes#qualifyStaticImport");
+      default:
+        return Description.NO_MATCH;
+    }
   }
 
   private Description createDescription(

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/util/AnnotationAttributeMatcher.java

@@ -1,4 +1,4 @@
-package tech.picnic.errorprone.utils;
+package tech.picnic.errorprone.bugpatterns.util;
 
 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.collect.HashMultimap;
@@ -9,6 +9,7 @@ import com.google.errorprone.util.ASTHelpers;
 import com.sun.source.tree.AnnotationTree;
 import com.sun.source.tree.AssignmentTree;
 import com.sun.source.tree.ExpressionTree;
+import com.sun.source.tree.Tree.Kind;
 import com.sun.tools.javac.code.Type;
 import java.io.Serializable;
 import java.util.HashSet;
@@ -115,8 +116,8 @@ public final class AnnotationAttributeMatcher implements Serializable {
   }
 
   private static String extractAttributeName(ExpressionTree expr) {
-    return (expr instanceof AssignmentTree assignment)
-        ? ASTHelpers.getSymbol(assignment.getVariable()).getSimpleName().toString()
+    return (expr.getKind() == Kind.ASSIGNMENT)
+        ? ASTHelpers.getSymbol(((AssignmentTree) expr).getVariable()).getSimpleName().toString()
         : "value";
   }
 

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/util/ConflictDetection.java

@@ -1,6 +1,6 @@
-package tech.picnic.errorprone.utils;
+package tech.picnic.errorprone.bugpatterns.util;
 
-import static tech.picnic.errorprone.utils.JavaKeywords.isValidIdentifier;
+import static tech.picnic.errorprone.bugpatterns.util.JavaKeywords.isValidIdentifier;
 
 import com.google.errorprone.VisitorState;
 import com.google.errorprone.util.ASTHelpers;

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/util/Documentation.java

@@ -1,4 +1,4 @@
-package tech.picnic.errorprone.utils;
+package tech.picnic.errorprone.bugpatterns.util;
 
 /** Utility class providing documentation-related code. */
 public final class Documentation {

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/util/Flags.java

@@ -1,4 +1,4 @@
-package tech.picnic.errorprone.utils;
+package tech.picnic.errorprone.bugpatterns.util;
 
 import com.google.common.collect.ImmutableList;
 import com.google.errorprone.ErrorProneFlags;

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/util/JavaKeywords.java

@@ -1,4 +1,4 @@
-package tech.picnic.errorprone.utils;
+package tech.picnic.errorprone.bugpatterns.util;
 
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Sets;

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/util/MethodMatcherFactory.java

@@ -1,4 +1,4 @@
-package tech.picnic.errorprone.utils;
+package tech.picnic.errorprone.bugpatterns.util;
 
 import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.common.collect.ImmutableSet.toImmutableSet;
@@ -45,6 +45,9 @@ public final class MethodMatcherFactory {
   // XXX: It seems parse errors are silently swallowed. Double-check; if true, file a ticket.
   // XXX: This (probably) doesn't work for methods with array type arguments; if true, implement a
   // fix.
+  // XXX: The `nullness` warning suppression shouldn't be necessary. See
+  // https://github.com/typetools/checker-framework/issues/4006.
+  @SuppressWarnings("nullness:argument")
   private static Matcher<ExpressionTree> createMethodMatcher(CharSequence signature) {
     java.util.regex.Matcher m = METHOD_SIGNATURE.matcher(signature);
     checkArgument(m.matches(), "Not a valid method signature: %s", signature);

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/util/MoreASTHelpers.java

@@ -1,4 +1,4 @@
-package tech.picnic.errorprone.utils;
+package tech.picnic.errorprone.bugpatterns.util;
 
 import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.common.collect.ImmutableList.toImmutableList;
@@ -15,7 +15,8 @@ import java.util.Optional;
 /**
  * A collection of helper methods for working with the AST.
  *
- * <p>These methods are additions to the ones found in {@link ASTHelpers}.
+ * <p>These methods are additions to the ones found in {@link
+ * com.google.errorprone.util.ASTHelpers}.
  */
 public final class MoreASTHelpers {
   private MoreASTHelpers() {}

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/util/MoreJUnitMatchers.java

@@ -1,4 +1,4 @@
-package tech.picnic.errorprone.utils;
+package tech.picnic.errorprone.bugpatterns.util;
 
 import static com.google.common.collect.ImmutableList.toImmutableList;
 import static com.google.errorprone.matchers.ChildMultiMatcher.MatchType.AT_LEAST_ONE;
@@ -6,7 +6,7 @@ import static com.google.errorprone.matchers.Matchers.annotations;
 import static com.google.errorprone.matchers.Matchers.anyOf;
 import static com.google.errorprone.matchers.Matchers.isType;
 import static java.util.Objects.requireNonNullElse;
-import static tech.picnic.errorprone.utils.MoreMatchers.hasMetaAnnotation;
+import static tech.picnic.errorprone.bugpatterns.util.MoreMatchers.hasMetaAnnotation;
 
 import com.google.common.base.Strings;
 import com.google.common.collect.ImmutableList;
@@ -99,13 +99,14 @@ public final class MoreJUnitMatchers {
     String methodName = method.getName().toString();
     ExpressionTree value = AnnotationMatcherUtils.getArgument(methodSourceAnnotation, "value");
 
-    if (!(value instanceof NewArrayTree newArray)) {
+    if (!(value instanceof NewArrayTree)) {
       return ImmutableList.of(toMethodSourceFactoryDescriptor(value, methodName));
     }
 
-    return newArray.getInitializers().stream()
-        .map(name -> toMethodSourceFactoryDescriptor(name, methodName))
-        .collect(toImmutableList());
+    return ((NewArrayTree) value)
+        .getInitializers().stream()
+            .map(name -> toMethodSourceFactoryDescriptor(name, methodName))
+            .collect(toImmutableList());
   }
 
   private static String toMethodSourceFactoryDescriptor(

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/util/MoreMatchers.java

@@ -1,7 +1,7 @@
-package tech.picnic.errorprone.utils;
+package tech.picnic.errorprone.bugpatterns.util;
 
 import static com.google.errorprone.matchers.Matchers.typePredicateMatcher;
-import static tech.picnic.errorprone.utils.MoreTypePredicates.hasAnnotation;
+import static tech.picnic.errorprone.bugpatterns.util.MoreTypePredicates.hasAnnotation;
 
 import com.google.errorprone.matchers.Matcher;
 import com.google.errorprone.matchers.Matchers;

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/util/MoreTypePredicates.java

@@ -1,4 +1,4 @@
-package tech.picnic.errorprone.utils;
+package tech.picnic.errorprone.bugpatterns.util;
 
 import com.google.errorprone.VisitorState;
 import com.google.errorprone.predicates.TypePredicate;

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/util/MoreTypes.java

@@ -1,4 +1,4 @@
-package tech.picnic.errorprone.utils;
+package tech.picnic.errorprone.bugpatterns.util;
 
 import static java.util.stream.Collectors.toCollection;
 

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/util/SourceCode.java

@@ -1,4 +1,4 @@
-package tech.picnic.errorprone.utils;
+package tech.picnic.errorprone.bugpatterns.util;
 
 import static com.sun.tools.javac.parser.Tokens.TokenKind.RPAREN;
 import static com.sun.tools.javac.util.Position.NOPOS;

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/util/ThirdPartyLibrary.java

@@ -1,4 +1,4 @@
-package tech.picnic.errorprone.utils;
+package tech.picnic.errorprone.bugpatterns.util;
 
 import com.google.common.collect.ImmutableList;
 import com.google.errorprone.VisitorState;
@@ -6,13 +6,10 @@ import com.google.errorprone.bugpatterns.BugChecker;
 import com.google.errorprone.suppliers.Supplier;
 import com.sun.tools.javac.code.ClassFinder;
 import com.sun.tools.javac.code.Source;
-import com.sun.tools.javac.code.Symbol;
 import com.sun.tools.javac.code.Symbol.CompletionFailure;
 import com.sun.tools.javac.code.Symbol.ModuleSymbol;
 import com.sun.tools.javac.code.Symtab;
-import com.sun.tools.javac.code.Type;
 import com.sun.tools.javac.util.Name;
-import javax.lang.model.element.Modifier;
 
 /**
  * Utility class that helps decide whether it is appropriate to introduce references to (well-known)
@@ -73,12 +70,12 @@ public enum ThirdPartyLibrary {
   /**
    * Tells whether the given fully qualified type is available on the current class path.
    *
-   * @param typeName The type of interest.
+   * @param className The type of interest.
    * @param state The context under consideration.
    * @return {@code true} iff it is okay to assume or create a dependency on this type.
    */
-  public static boolean canIntroduceUsage(String typeName, VisitorState state) {
-    return shouldIgnoreClasspath(state) || isKnownClass(typeName, state);
+  public static boolean canIntroduceUsage(String className, VisitorState state) {
+    return shouldIgnoreClasspath(state) || isKnownClass(className, state);
   }
 
   /**
@@ -87,16 +84,11 @@ public enum ThirdPartyLibrary {
    * <p>The {@link VisitorState}'s symbol table is consulted first. If the type has not yet been
    * loaded, then an attempt is made to do so.
    */
-  private static boolean isKnownClass(String typeName, VisitorState state) {
-    return isPublicClassInSymbolTable(typeName, state) || canLoadPublicClass(typeName, state);
+  private static boolean isKnownClass(String className, VisitorState state) {
+    return state.getTypeFromString(className) != null || canLoadClass(className, state);
   }
 
-  private static boolean isPublicClassInSymbolTable(String typeName, VisitorState state) {
-    Type type = state.getTypeFromString(typeName);
-    return type != null && isPublic(type.tsym);
-  }
-
-  private static boolean canLoadPublicClass(String typeName, VisitorState state) {
+  private static boolean canLoadClass(String className, VisitorState state) {
     ClassFinder classFinder = ClassFinder.instance(state.context);
     Symtab symtab = state.getSymtab();
     // XXX: Drop support for targeting Java 8 once the oldest supported JDK drops such support.
@@ -104,9 +96,10 @@ public enum ThirdPartyLibrary {
         Source.instance(state.context).compareTo(Source.JDK9) < 0
             ? symtab.noModule
             : symtab.unnamedModule;
-    Name binaryName = state.binaryNameFromClassname(typeName);
+    Name binaryName = state.binaryNameFromClassname(className);
     try {
-      return isPublic(classFinder.loadClass(module, binaryName));
+      classFinder.loadClass(module, binaryName);
+      return true;
     } catch (
         @SuppressWarnings("java:S1166" /* Not exceptional. */)
         CompletionFailure e) {
@@ -114,11 +107,6 @@ public enum ThirdPartyLibrary {
     }
   }
 
-  // XXX: Once we target JDK 14+, drop this method in favour of `Symbol#isPublic()`.
-  private static boolean isPublic(Symbol symbol) {
-    return symbol.getModifiers().contains(Modifier.PUBLIC);
-  }
-
   private static boolean shouldIgnoreClasspath(VisitorState state) {
     return state
         .errorProneOptions()

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/util/package-info.java

@@ -1,4 +1,4 @@
 /** Auxiliary utilities for use by Error Prone checks. */
 @com.google.errorprone.annotations.CheckReturnValue
 @org.jspecify.annotations.NullMarked
-package tech.picnic.errorprone.utils;
+package tech.picnic.errorprone.bugpatterns.util;

error-prone-contrib/src/main/java/tech/picnic/errorprone/refasterrules/AssertJRules.java

@@ -530,13 +530,13 @@ final class AssertJRules {
   static final class AssertThatStreamContainsAnyElementsOf<S, T extends S, U extends T> {
     @BeforeTemplate
     IterableAssert<T> before(
-        Stream<S> stream, Iterable<U> iterable, Collector<S, ?, ? extends Iterable<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends Iterable<T>> collector, Iterable<U> iterable) {
       return assertThat(stream.collect(collector)).containsAnyElementsOf(iterable);
     }
 
     @BeforeTemplate
     ListAssert<T> before2(
-        Stream<S> stream, Iterable<U> iterable, Collector<S, ?, ? extends List<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends List<T>> collector, Iterable<U> iterable) {
       return assertThat(stream.collect(collector)).containsAnyElementsOf(iterable);
     }
 
@@ -551,13 +551,13 @@ final class AssertJRules {
   static final class AssertThatStreamContainsAnyOf<S, T extends S, U extends T> {
     @BeforeTemplate
     IterableAssert<T> before(
-        Stream<S> stream, U[] array, Collector<S, ?, ? extends Iterable<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends Iterable<T>> collector, U[] array) {
       return assertThat(stream.collect(collector)).containsAnyOf(array);
     }
 
     @BeforeTemplate
     ListAssert<T> before2(
-        Stream<S> stream, U[] array, Collector<S, ?, ? extends List<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends List<T>> collector, U[] array) {
       return assertThat(stream.collect(collector)).containsAnyOf(array);
     }
 
@@ -573,14 +573,14 @@ final class AssertJRules {
     @BeforeTemplate
     @SuppressWarnings("AssertThatStreamContainsAnyOf" /* Varargs converted to array. */)
     IterableAssert<T> before(
-        Stream<S> stream, @Repeated U elements, Collector<S, ?, ? extends Iterable<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends Iterable<T>> collector, @Repeated U elements) {
       return assertThat(stream.collect(collector)).containsAnyOf(Refaster.asVarargs(elements));
     }
 
     @BeforeTemplate
     @SuppressWarnings("AssertThatStreamContainsAnyOf" /* Varargs converted to array. */)
     ListAssert<T> before2(
-        Stream<S> stream, @Repeated U elements, Collector<S, ?, ? extends List<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends List<T>> collector, @Repeated U elements) {
       return assertThat(stream.collect(collector)).containsAnyOf(Refaster.asVarargs(elements));
     }
 
@@ -596,13 +596,13 @@ final class AssertJRules {
   static final class AssertThatStreamContainsAll<S, T extends S, U extends T> {
     @BeforeTemplate
     IterableAssert<T> before(
-        Stream<S> stream, Iterable<U> iterable, Collector<S, ?, ? extends Iterable<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends Iterable<T>> collector, Iterable<U> iterable) {
       return assertThat(stream.collect(collector)).containsAll(iterable);
     }
 
     @BeforeTemplate
     ListAssert<T> before2(
-        Stream<S> stream, Iterable<U> iterable, Collector<S, ?, ? extends List<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends List<T>> collector, Iterable<U> iterable) {
       return assertThat(stream.collect(collector)).containsAll(iterable);
     }
 
@@ -617,13 +617,13 @@ final class AssertJRules {
   static final class AssertThatStreamContains<S, T extends S, U extends T> {
     @BeforeTemplate
     IterableAssert<T> before(
-        Stream<S> stream, U[] array, Collector<S, ?, ? extends Iterable<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends Iterable<T>> collector, U[] array) {
       return assertThat(stream.collect(collector)).contains(array);
     }
 
     @BeforeTemplate
     ListAssert<T> before2(
-        Stream<S> stream, U[] array, Collector<S, ?, ? extends List<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends List<T>> collector, U[] array) {
       return assertThat(stream.collect(collector)).contains(array);
     }
 
@@ -639,14 +639,14 @@ final class AssertJRules {
     @BeforeTemplate
     @SuppressWarnings("AssertThatStreamContains" /* Varargs converted to array. */)
     IterableAssert<T> before(
-        Stream<S> stream, @Repeated U elements, Collector<S, ?, ? extends Iterable<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends Iterable<T>> collector, @Repeated U elements) {
       return assertThat(stream.collect(collector)).contains(Refaster.asVarargs(elements));
     }
 
     @BeforeTemplate
     @SuppressWarnings("AssertThatStreamContains" /* Varargs converted to array. */)
     ListAssert<T> before2(
-        Stream<S> stream, @Repeated U elements, Collector<S, ?, ? extends List<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends List<T>> collector, @Repeated U elements) {
       return assertThat(stream.collect(collector)).contains(Refaster.asVarargs(elements));
     }
 
@@ -661,7 +661,7 @@ final class AssertJRules {
   static final class AssertThatStreamContainsExactlyElementsOf<S, T extends S, U extends T> {
     @BeforeTemplate
     ListAssert<T> before(
-        Stream<S> stream, Iterable<U> iterable, Collector<S, ?, ? extends List<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends List<T>> collector, Iterable<U> iterable) {
       return assertThat(stream.collect(collector)).containsExactlyElementsOf(iterable);
     }
 
@@ -676,7 +676,7 @@ final class AssertJRules {
   static final class AssertThatStreamContainsExactly<S, T extends S, U extends T> {
     @BeforeTemplate
     ListAssert<T> before(
-        Stream<S> stream, U[] array, Collector<S, ?, ? extends List<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends List<T>> collector, U[] array) {
       return assertThat(stream.collect(collector)).containsExactly(array);
     }
 
@@ -692,7 +692,7 @@ final class AssertJRules {
     @BeforeTemplate
     @SuppressWarnings("AssertThatStreamContainsExactly" /* Varargs converted to array. */)
     ListAssert<T> before(
-        Stream<S> stream, @Repeated U elements, Collector<S, ?, ? extends List<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends List<T>> collector, @Repeated U elements) {
       return assertThat(stream.collect(collector)).containsExactly(Refaster.asVarargs(elements));
     }
 
@@ -708,13 +708,13 @@ final class AssertJRules {
       S, T extends S, U extends T> {
     @BeforeTemplate
     ListAssert<T> before(
-        Stream<S> stream, Iterable<U> iterable, Collector<S, ?, ? extends List<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends List<T>> collector, Iterable<U> iterable) {
       return assertThat(stream.collect(collector)).containsExactlyInAnyOrderElementsOf(iterable);
     }
 
     @BeforeTemplate
     AbstractCollectionAssert<?, ?, T, ?> before2(
-        Stream<S> stream, Iterable<U> iterable, Collector<S, ?, ? extends Multiset<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends Multiset<T>> collector, Iterable<U> iterable) {
       return assertThat(stream.collect(collector)).containsExactlyInAnyOrderElementsOf(iterable);
     }
 
@@ -729,13 +729,13 @@ final class AssertJRules {
   static final class AssertThatStreamContainsExactlyInAnyOrder<S, T extends S, U extends T> {
     @BeforeTemplate
     ListAssert<T> before(
-        Stream<S> stream, U[] array, Collector<S, ?, ? extends List<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends List<T>> collector, U[] array) {
       return assertThat(stream.collect(collector)).containsExactlyInAnyOrder(array);
     }
 
     @BeforeTemplate
     AbstractCollectionAssert<?, ?, T, ?> before2(
-        Stream<S> stream, U[] array, Collector<S, ?, ? extends Multiset<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends Multiset<T>> collector, U[] array) {
       return assertThat(stream.collect(collector)).containsExactlyInAnyOrder(array);
     }
 
@@ -751,7 +751,7 @@ final class AssertJRules {
     @BeforeTemplate
     @SuppressWarnings("AssertThatStreamContainsExactlyInAnyOrder" /* Varargs converted to array. */)
     ListAssert<T> before(
-        Stream<S> stream, @Repeated U elements, Collector<S, ?, ? extends List<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends List<T>> collector, @Repeated U elements) {
       return assertThat(stream.collect(collector))
           .containsExactlyInAnyOrder(Refaster.asVarargs(elements));
     }
@@ -759,7 +759,7 @@ final class AssertJRules {
     @BeforeTemplate
     @SuppressWarnings("AssertThatStreamContainsExactlyInAnyOrder" /* Varargs converted to array. */)
     AbstractCollectionAssert<?, ?, T, ?> before2(
-        Stream<S> stream, @Repeated U elements, Collector<S, ?, ? extends Multiset<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends Multiset<T>> collector, @Repeated U elements) {
       return assertThat(stream.collect(collector))
           .containsExactlyInAnyOrder(Refaster.asVarargs(elements));
     }
@@ -776,13 +776,13 @@ final class AssertJRules {
   static final class AssertThatStreamContainsSequence<S, T extends S, U extends T> {
     @BeforeTemplate
     ListAssert<T> before(
-        Stream<S> stream, Iterable<U> iterable, Collector<S, ?, ? extends List<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends List<T>> collector, Iterable<U> iterable) {
       return assertThat(stream.collect(collector)).containsSequence(iterable);
     }
 
     @BeforeTemplate
     ListAssert<T> before(
-        Stream<S> stream, U[] iterable, Collector<S, ?, ? extends List<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends List<T>> collector, U[] iterable) {
       return assertThat(stream.collect(collector)).containsSequence(iterable);
     }
 
@@ -798,7 +798,7 @@ final class AssertJRules {
     @BeforeTemplate
     @SuppressWarnings("AssertThatStreamContainsSequence" /* Varargs converted to array. */)
     ListAssert<T> before(
-        Stream<S> stream, @Repeated U elements, Collector<S, ?, ? extends List<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends List<T>> collector, @Repeated U elements) {
       return assertThat(stream.collect(collector)).containsSequence(Refaster.asVarargs(elements));
     }
 
@@ -814,13 +814,13 @@ final class AssertJRules {
   static final class AssertThatStreamContainsSubsequence<S, T extends S, U extends T> {
     @BeforeTemplate
     ListAssert<T> before(
-        Stream<S> stream, Iterable<U> iterable, Collector<S, ?, ? extends List<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends List<T>> collector, Iterable<U> iterable) {
       return assertThat(stream.collect(collector)).containsSubsequence(iterable);
     }
 
     @BeforeTemplate
     ListAssert<T> before(
-        Stream<S> stream, U[] iterable, Collector<S, ?, ? extends List<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends List<T>> collector, U[] iterable) {
       return assertThat(stream.collect(collector)).containsSubsequence(iterable);
     }
 
@@ -836,7 +836,7 @@ final class AssertJRules {
     @BeforeTemplate
     @SuppressWarnings("AssertThatStreamContainsSubsequence" /* Varargs converted to array. */)
     ListAssert<T> before(
-        Stream<S> stream, @Repeated U elements, Collector<S, ?, ? extends List<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends List<T>> collector, @Repeated U elements) {
       return assertThat(stream.collect(collector))
           .containsSubsequence(Refaster.asVarargs(elements));
     }
@@ -853,13 +853,13 @@ final class AssertJRules {
   static final class AssertThatStreamDoesNotContainAnyElementsOf<S, T extends S, U extends T> {
     @BeforeTemplate
     IterableAssert<T> before(
-        Stream<S> stream, Iterable<U> iterable, Collector<S, ?, ? extends Iterable<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends Iterable<T>> collector, Iterable<U> iterable) {
       return assertThat(stream.collect(collector)).doesNotContainAnyElementsOf(iterable);
     }
 
     @BeforeTemplate
     ListAssert<T> before2(
-        Stream<S> stream, Iterable<U> iterable, Collector<S, ?, ? extends List<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends List<T>> collector, Iterable<U> iterable) {
       return assertThat(stream.collect(collector)).doesNotContainAnyElementsOf(iterable);
     }
 
@@ -874,13 +874,13 @@ final class AssertJRules {
   static final class AssertThatStreamDoesNotContain<S, T extends S, U extends T> {
     @BeforeTemplate
     IterableAssert<T> before(
-        Stream<S> stream, U[] array, Collector<S, ?, ? extends Iterable<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends Iterable<T>> collector, U[] array) {
       return assertThat(stream.collect(collector)).doesNotContain(array);
     }
 
     @BeforeTemplate
     ListAssert<T> before2(
-        Stream<S> stream, U[] array, Collector<S, ?, ? extends List<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends List<T>> collector, U[] array) {
       return assertThat(stream.collect(collector)).doesNotContain(array);
     }
 
@@ -896,14 +896,14 @@ final class AssertJRules {
     @BeforeTemplate
     @SuppressWarnings("AssertThatStreamDoesNotContain" /* Varargs converted to array. */)
     IterableAssert<T> before(
-        Stream<S> stream, @Repeated U elements, Collector<S, ?, ? extends Iterable<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends Iterable<T>> collector, @Repeated U elements) {
       return assertThat(stream.collect(collector)).doesNotContain(Refaster.asVarargs(elements));
     }
 
     @BeforeTemplate
     @SuppressWarnings("AssertThatStreamDoesNotContain" /* Varargs converted to array. */)
     ListAssert<T> before2(
-        Stream<S> stream, @Repeated U elements, Collector<S, ?, ? extends List<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends List<T>> collector, @Repeated U elements) {
       return assertThat(stream.collect(collector)).doesNotContain(Refaster.asVarargs(elements));
     }
 
@@ -918,13 +918,13 @@ final class AssertJRules {
   static final class AssertThatStreamDoesNotContainSequence<S, T extends S, U extends T> {
     @BeforeTemplate
     ListAssert<T> before(
-        Stream<S> stream, Iterable<U> iterable, Collector<S, ?, ? extends List<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends List<T>> collector, Iterable<U> iterable) {
       return assertThat(stream.collect(collector)).doesNotContainSequence(iterable);
     }
 
     @BeforeTemplate
     ListAssert<T> before(
-        Stream<S> stream, U[] iterable, Collector<S, ?, ? extends List<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends List<T>> collector, U[] iterable) {
       return assertThat(stream.collect(collector)).doesNotContainSequence(iterable);
     }
 
@@ -940,7 +940,7 @@ final class AssertJRules {
     @BeforeTemplate
     @SuppressWarnings("AssertThatStreamDoesNotContainSequence" /* Varargs converted to array. */)
     ListAssert<T> before(
-        Stream<S> stream, @Repeated U elements, Collector<S, ?, ? extends List<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends List<T>> collector, @Repeated U elements) {
       return assertThat(stream.collect(collector))
           .doesNotContainSequence(Refaster.asVarargs(elements));
     }
@@ -957,13 +957,13 @@ final class AssertJRules {
   static final class AssertThatStreamHasSameElementsAs<S, T extends S, U extends T> {
     @BeforeTemplate
     IterableAssert<T> before(
-        Stream<S> stream, Iterable<U> iterable, Collector<S, ?, ? extends Iterable<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends Iterable<T>> collector, Iterable<U> iterable) {
       return assertThat(stream.collect(collector)).hasSameElementsAs(iterable);
     }
 
     @BeforeTemplate
     ListAssert<T> before2(
-        Stream<S> stream, Iterable<U> iterable, Collector<S, ?, ? extends List<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends List<T>> collector, Iterable<U> iterable) {
       return assertThat(stream.collect(collector)).hasSameElementsAs(iterable);
     }
 
@@ -978,13 +978,13 @@ final class AssertJRules {
   static final class AssertThatStreamContainsOnly<S, T extends S, U extends T> {
     @BeforeTemplate
     IterableAssert<T> before(
-        Stream<S> stream, U[] array, Collector<S, ?, ? extends Iterable<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends Iterable<T>> collector, U[] array) {
       return assertThat(stream.collect(collector)).containsOnly(array);
     }
 
     @BeforeTemplate
     ListAssert<T> before2(
-        Stream<S> stream, U[] array, Collector<S, ?, ? extends List<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends List<T>> collector, U[] array) {
       return assertThat(stream.collect(collector)).containsOnly(array);
     }
 
@@ -1000,14 +1000,14 @@ final class AssertJRules {
     @BeforeTemplate
     @SuppressWarnings("AssertThatStreamContainsOnly" /* Varargs converted to array. */)
     IterableAssert<T> before(
-        Stream<S> stream, @Repeated U elements, Collector<S, ?, ? extends Iterable<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends Iterable<T>> collector, @Repeated U elements) {
       return assertThat(stream.collect(collector)).containsOnly(Refaster.asVarargs(elements));
     }
 
     @BeforeTemplate
     @SuppressWarnings("AssertThatStreamContainsOnly" /* Varargs converted to array. */)
     ListAssert<T> before2(
-        Stream<S> stream, @Repeated U elements, Collector<S, ?, ? extends List<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends List<T>> collector, @Repeated U elements) {
       return assertThat(stream.collect(collector)).containsOnly(Refaster.asVarargs(elements));
     }
 
@@ -1022,25 +1022,25 @@ final class AssertJRules {
   static final class AssertThatStreamIsSubsetOf<S, T extends S, U extends T> {
     @BeforeTemplate
     IterableAssert<T> before(
-        Stream<S> stream, Iterable<U> iterable, Collector<S, ?, ? extends Iterable<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends Iterable<T>> collector, Iterable<U> iterable) {
       return assertThat(stream.collect(collector)).isSubsetOf(iterable);
     }
 
     @BeforeTemplate
     IterableAssert<T> before(
-        Stream<S> stream, U[] iterable, Collector<S, ?, ? extends Iterable<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends Iterable<T>> collector, U[] iterable) {
       return assertThat(stream.collect(collector)).isSubsetOf(iterable);
     }
 
     @BeforeTemplate
     ListAssert<T> before2(
-        Stream<S> stream, Iterable<U> iterable, Collector<S, ?, ? extends List<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends List<T>> collector, Iterable<U> iterable) {
       return assertThat(stream.collect(collector)).isSubsetOf(iterable);
     }
 
     @BeforeTemplate
     ListAssert<T> before2(
-        Stream<S> stream, U[] iterable, Collector<S, ?, ? extends List<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends List<T>> collector, U[] iterable) {
       return assertThat(stream.collect(collector)).isSubsetOf(iterable);
     }
 
@@ -1056,14 +1056,14 @@ final class AssertJRules {
     @BeforeTemplate
     @SuppressWarnings("AssertThatStreamIsSubsetOf" /* Varargs converted to array. */)
     IterableAssert<T> before(
-        Stream<S> stream, @Repeated U elements, Collector<S, ?, ? extends Iterable<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends Iterable<T>> collector, @Repeated U elements) {
       return assertThat(stream.collect(collector)).isSubsetOf(Refaster.asVarargs(elements));
     }
 
     @BeforeTemplate
     @SuppressWarnings("AssertThatStreamIsSubsetOf" /* Varargs converted to array. */)
     ListAssert<T> before2(
-        Stream<S> stream, @Repeated U elements, Collector<S, ?, ? extends List<T>> collector) {
+        Stream<S> stream, Collector<S, ?, ? extends List<T>> collector, @Repeated U elements) {
       return assertThat(stream.collect(collector)).isSubsetOf(Refaster.asVarargs(elements));
     }
 

error-prone-contrib/src/main/java/tech/picnic/errorprone/refasterrules/AssertJStringRules.java

@@ -13,6 +13,7 @@ import java.nio.file.Files;
 import java.nio.file.Path;
 import org.assertj.core.api.AbstractAssert;
 import org.assertj.core.api.AbstractStringAssert;
+import org.checkerframework.checker.regex.qual.Regex;
 import tech.picnic.errorprone.refaster.annotation.OnlineDocumentation;
 
 @OnlineDocumentation
@@ -71,26 +72,26 @@ final class AssertJStringRules {
 
   static final class AssertThatMatches {
     @BeforeTemplate
-    AbstractAssert<?, ?> before(String string, String regex) {
+    AbstractAssert<?, ?> before(String string, @Regex String regex) {
       return assertThat(string.matches(regex)).isTrue();
     }
 
     @AfterTemplate
     @UseImportPolicy(STATIC_IMPORT_ALWAYS)
-    AbstractAssert<?, ?> after(String string, String regex) {
+    AbstractAssert<?, ?> after(String string, @Regex String regex) {
       return assertThat(string).matches(regex);
     }
   }
 
   static final class AssertThatDoesNotMatch {
     @BeforeTemplate
-    AbstractAssert<?, ?> before(String string, String regex) {
+    AbstractAssert<?, ?> before(String string, @Regex String regex) {
       return assertThat(string.matches(regex)).isFalse();
     }
 
     @AfterTemplate
     @UseImportPolicy(STATIC_IMPORT_ALWAYS)
-    AbstractAssert<?, ?> after(String string, String regex) {
+    AbstractAssert<?, ?> after(String string, @Regex String regex) {
       return assertThat(string).doesNotMatch(regex);
     }
   }