[refactor] Use getType in ModelUtils (#18577)

* use getType in model utils

* add tests

* update

modules/openapi-generator/src/main/java/org/openapitools/codegen/DefaultCodegen.java

@@ -2492,10 +2492,10 @@ public class DefaultCodegen implements CodegenConfig {
     private String getPrimitiveType(Schema schema) {
         if (schema == null) {
             throw new RuntimeException("schema cannot be null in getPrimitiveType");
-        } else if (typeMapping.containsKey(schema.getType() + "+" + schema.getFormat())) {
+        } else if (typeMapping.containsKey(ModelUtils.getType(schema) + "+" + schema.getFormat())) {
             // allows custom type_format mapping.
             // use {type}+{format}
-            return typeMapping.get(schema.getType() + "+" + schema.getFormat());
+            return typeMapping.get(ModelUtils.getType(schema) + "+" + schema.getFormat());
         } else if (ModelUtils.isNullType(schema)) {
             // The 'null' type is allowed in OAS 3.1 and above. It is not supported by OAS 3.0.x,
             // though this tooling supports it.
@@ -2536,7 +2536,7 @@ public class DefaultCodegen implements CodegenConfig {
             } else if (ModelUtils.isShortSchema(schema)) {// int32
                 return "integer";
             } else {
-                return schema.getType(); // integer
+                return ModelUtils.getType(schema); // integer
             }
         } else if (ModelUtils.isMapSchema(schema)) {
             return "map";
@@ -2567,11 +2567,11 @@ public class DefaultCodegen implements CodegenConfig {
             return "object";
         } else if (ModelUtils.isAnyType(schema)) {
             return "AnyType";
-        } else if (StringUtils.isNotEmpty(schema.getType())) {
-            if (!schemaMapping.containsKey(schema.getType())) {
-                LOGGER.warn("Unknown type found in the schema: {}. To map it, please use the schema mapping option (e.g. --schema-mappings in CLI)", schema.getType());
+        } else if (StringUtils.isNotEmpty(ModelUtils.getType(schema))) {
+            if (!schemaMapping.containsKey(ModelUtils.getType(schema))) {
+                LOGGER.warn("Unknown type found in the schema: {}. To map it, please use the schema mapping option (e.g. --schema-mappings in CLI)", ModelUtils.getType(schema));
             }
-            return schema.getType();
+            return ModelUtils.getType(schema);
         }
         // The 'type' attribute has not been set in the OAS schema, which means the value
         // can be an arbitrary type, e.g. integer, string, object, array, number...
@@ -4019,10 +4019,10 @@ public class DefaultCodegen implements CodegenConfig {
 
         property.name = toVarName(name);
         property.baseName = name;
-        if (p.getType() == null) {
+        if (ModelUtils.getType(p) == null) {
             property.openApiType = getSchemaType(p);
         } else {
-            property.openApiType = p.getType();
+            property.openApiType = ModelUtils.getType(p);
         }
         property.nameInPascalCase = camelize(property.name);
         property.nameInCamelCase = camelize(property.name, LOWERCASE_FIRST_LETTER);
@@ -7128,7 +7128,7 @@ public class DefaultCodegen implements CodegenConfig {
         Schema original = null;
         // check if it's allOf (only 1 sub schema) with or without default/nullable/etc set in the top level
         if (ModelUtils.isAllOf(schema) && schema.getAllOf().size() == 1 &&
-                schema.getType() == null && schema.getTypes() == null) {
+                ModelUtils.getType(schema) == null) {
             if (schema.getAllOf().get(0) instanceof Schema) {
                 original = schema;
                 schema = (Schema) schema.getAllOf().get(0);
@@ -7781,7 +7781,7 @@ public class DefaultCodegen implements CodegenConfig {
         Schema original = null;
         // check if it's allOf (only 1 sub schema) with or without default/nullable/etc set in the top level
         if (ModelUtils.isAllOf(schema) && schema.getAllOf().size() == 1 &&
-                schema.getType() == null && schema.getTypes() == null) {
+                ModelUtils.getType(schema) == null) {
             if (schema.getAllOf().get(0) instanceof Schema) {
                 original = schema;
                 schema = (Schema) schema.getAllOf().get(0);

modules/openapi-generator/src/main/java/org/openapitools/codegen/utils/ModelUtils.java

@@ -419,16 +419,7 @@ public class ModelUtils {
      * @return true if the specified schema is an Object schema.
      */
     public static boolean isTypeObjectSchema(Schema schema) {
-        if (schema instanceof JsonSchema) { // 3.1 spec
-            if (schema.getTypes() != null && schema.getTypes().size() == 1) {
-                return SchemaTypeUtil.OBJECT_TYPE.equals(schema.getTypes().iterator().next());
-            } else {
-                // null type or  multiple types, e.g. [string, integer]
-                return false;
-            }
-        } else { // 3.0.x or 2.0 spec
-            return SchemaTypeUtil.OBJECT_TYPE.equals(schema.getType());
-        }
+        return SchemaTypeUtil.OBJECT_TYPE.equals(getType(schema));
     }
 
     /**
@@ -460,9 +451,9 @@ public class ModelUtils {
 
         return (schema instanceof ObjectSchema) ||
                 // must not be a map
-                (SchemaTypeUtil.OBJECT_TYPE.equals(schema.getType()) && !(ModelUtils.isMapSchema(schema))) ||
+                (SchemaTypeUtil.OBJECT_TYPE.equals(getType(schema)) && !(ModelUtils.isMapSchema(schema))) ||
                 // must have at least one property
-                (schema.getType() == null && schema.getProperties() != null && !schema.getProperties().isEmpty());
+                (getType(schema) == null && schema.getProperties() != null && !schema.getProperties().isEmpty());
     }
 
     /**
@@ -594,17 +585,7 @@ public class ModelUtils {
         if (schema == null) {
             return false;
         }
-
-        if (schema instanceof JsonSchema) { // 3.1 spec
-            if (schema.getTypes() != null && schema.getTypes().contains("array")) {
-                return true;
-            } else {
-                return false;
-            }
-        } else { // 3.0 spec
-            return (schema instanceof ArraySchema) || "array".equals(schema.getType());
-        }
-
+        return (schema instanceof ArraySchema) || "array".equals(getType(schema));
     }
 
     /**
@@ -636,89 +617,89 @@ public class ModelUtils {
     }
 
     public static boolean isStringSchema(Schema schema) {
-        return schema instanceof StringSchema || SchemaTypeUtil.STRING_TYPE.equals(schema.getType());
+        return schema instanceof StringSchema || SchemaTypeUtil.STRING_TYPE.equals(getType(schema));
     }
 
     public static boolean isIntegerSchema(Schema schema) {
-        return schema instanceof IntegerSchema || SchemaTypeUtil.INTEGER_TYPE.equals(schema.getType());
+        return schema instanceof IntegerSchema || SchemaTypeUtil.INTEGER_TYPE.equals(getType(schema));
     }
 
     public static boolean isShortSchema(Schema schema) {
         // format: short (int32)
-        return SchemaTypeUtil.INTEGER_TYPE.equals(schema.getType()) // type: integer
+        return SchemaTypeUtil.INTEGER_TYPE.equals(getType(schema)) // type: integer
                 && SchemaTypeUtil.INTEGER32_FORMAT.equals(schema.getFormat());
     }
 
     public static boolean isUnsignedIntegerSchema(Schema schema) {
-        return SchemaTypeUtil.INTEGER_TYPE.equals(schema.getType()) && // type: integer
+        return SchemaTypeUtil.INTEGER_TYPE.equals(getType(schema)) && // type: integer
                 ("int32".equals(schema.getFormat()) || schema.getFormat() == null) && // format: int32
                 (schema.getExtensions() != null && (Boolean) schema.getExtensions().getOrDefault("x-unsigned", Boolean.FALSE));
     }
 
     public static boolean isLongSchema(Schema schema) {
         // format: long (int64)
-        return SchemaTypeUtil.INTEGER_TYPE.equals(schema.getType()) // type: integer
+        return SchemaTypeUtil.INTEGER_TYPE.equals(getType(schema)) // type: integer
                 && SchemaTypeUtil.INTEGER64_FORMAT.equals(schema.getFormat());
     }
 
     public static boolean isUnsignedLongSchema(Schema schema) {
-        return SchemaTypeUtil.INTEGER_TYPE.equals(schema.getType()) && // type: integer
+        return SchemaTypeUtil.INTEGER_TYPE.equals(getType(schema)) && // type: integer
                 "int64".equals(schema.getFormat()) && // format: int64
                 (schema.getExtensions() != null && (Boolean) schema.getExtensions().getOrDefault("x-unsigned", Boolean.FALSE));
     }
 
     public static boolean isBooleanSchema(Schema schema) {
-        return schema instanceof BooleanSchema || SchemaTypeUtil.BOOLEAN_TYPE.equals(schema.getType());
+        return schema instanceof BooleanSchema || SchemaTypeUtil.BOOLEAN_TYPE.equals(getType(schema));
     }
 
     public static boolean isNumberSchema(Schema schema) {
-        return schema instanceof NumberSchema || SchemaTypeUtil.NUMBER_TYPE.equals(schema.getType());
+        return schema instanceof NumberSchema || SchemaTypeUtil.NUMBER_TYPE.equals(getType(schema));
     }
 
     public static boolean isFloatSchema(Schema schema) {
         // format: float
-        return SchemaTypeUtil.NUMBER_TYPE.equals(schema.getType())
+        return SchemaTypeUtil.NUMBER_TYPE.equals(getType(schema))
                 && SchemaTypeUtil.FLOAT_FORMAT.equals(schema.getFormat());
     }
 
     public static boolean isDoubleSchema(Schema schema) {
         // format: double
-        return SchemaTypeUtil.NUMBER_TYPE.equals(schema.getType())
+        return SchemaTypeUtil.NUMBER_TYPE.equals(getType(schema))
                 && SchemaTypeUtil.DOUBLE_FORMAT.equals(schema.getFormat());
     }
 
     public static boolean isDateSchema(Schema schema) {
         return (schema instanceof DateSchema) ||
                 // format: date
-                (SchemaTypeUtil.STRING_TYPE.equals(schema.getType())
+                (SchemaTypeUtil.STRING_TYPE.equals(getType(schema))
                         && SchemaTypeUtil.DATE_FORMAT.equals(schema.getFormat()));
     }
 
     public static boolean isDateTimeSchema(Schema schema) {
         return (schema instanceof DateTimeSchema) ||
                 // format: date-time
-                (SchemaTypeUtil.STRING_TYPE.equals(schema.getType())
+                (SchemaTypeUtil.STRING_TYPE.equals(getType(schema))
                         && SchemaTypeUtil.DATE_TIME_FORMAT.equals(schema.getFormat()));
     }
 
     public static boolean isPasswordSchema(Schema schema) {
         return (schema instanceof PasswordSchema) ||
                 // double
-                (SchemaTypeUtil.STRING_TYPE.equals(schema.getType())
+                (SchemaTypeUtil.STRING_TYPE.equals(getType(schema))
                         && SchemaTypeUtil.PASSWORD_FORMAT.equals(schema.getFormat()));
     }
 
     public static boolean isByteArraySchema(Schema schema) {
         return (schema instanceof ByteArraySchema) ||
                 // format: byte
-                (SchemaTypeUtil.STRING_TYPE.equals(schema.getType())
+                (SchemaTypeUtil.STRING_TYPE.equals(getType(schema))
                         && SchemaTypeUtil.BYTE_FORMAT.equals(schema.getFormat()));
     }
 
     public static boolean isBinarySchema(Schema schema) {
         return (schema instanceof BinarySchema) ||
                 // format: binary
-                (SchemaTypeUtil.STRING_TYPE.equals(schema.getType())
+                (SchemaTypeUtil.STRING_TYPE.equals(getType(schema))
                         && SchemaTypeUtil.BINARY_FORMAT.equals(schema.getFormat()));
     }
 
@@ -731,26 +712,26 @@ public class ModelUtils {
     public static boolean isUUIDSchema(Schema schema) {
         return (schema instanceof UUIDSchema) ||
                 // format: uuid
-                (SchemaTypeUtil.STRING_TYPE.equals(schema.getType())
+                (SchemaTypeUtil.STRING_TYPE.equals(getType(schema))
                         && SchemaTypeUtil.UUID_FORMAT.equals(schema.getFormat()));
     }
 
     public static boolean isURISchema(Schema schema) {
         // format: uri
-        return SchemaTypeUtil.STRING_TYPE.equals(schema.getType())
+        return SchemaTypeUtil.STRING_TYPE.equals(getType(schema))
                 && URI_FORMAT.equals(schema.getFormat());
     }
 
     public static boolean isEmailSchema(Schema schema) {
         return (schema instanceof EmailSchema) ||
                 // format: email
-                (SchemaTypeUtil.STRING_TYPE.equals(schema.getType())
+                (SchemaTypeUtil.STRING_TYPE.equals(getType(schema))
                         && SchemaTypeUtil.EMAIL_FORMAT.equals(schema.getFormat()));
     }
 
     public static boolean isDecimalSchema(Schema schema) {
         // format: number
-        return SchemaTypeUtil.STRING_TYPE.equals(schema.getType()) // type: string
+        return SchemaTypeUtil.STRING_TYPE.equals(getType(schema)) // type: string
                 && "number".equals(schema.getFormat());
     }
 
@@ -898,7 +879,7 @@ public class ModelUtils {
         }
 
         // has at least one property
-        if ("object".equals(schema.getType())) {
+        if ("object".equals(getType(schema))) {
             // no properties
             if ((schema.getProperties() == null || schema.getProperties().isEmpty())) {
                 Schema addlProps = ModelUtils.getAdditionalProperties(schema);
@@ -1782,7 +1763,7 @@ public class ModelUtils {
      * @return true if the schema is the 'null' type
      */
     public static boolean isNullType(Schema schema) {
-        return "null".equals(schema.getType());
+        return "null".equals(getType(schema));
     }
 
     /**
@@ -1798,7 +1779,7 @@ public class ModelUtils {
         // TODO remove the ref check here, or pass in the spec version
         // openapi 3.1.0 specs allow ref to be adjacent to any keyword
         // openapi 3.0.3 and earlier do not allow adjacent keywords to refs
-        return (schema.get$ref() == null && schema.getType() == null);
+        return (schema.get$ref() == null && getType(schema) == null);
     }
 
     public static void syncValidationProperties(Schema schema, IJsonSchemaValidationProperties target) {
@@ -1930,7 +1911,7 @@ public class ModelUtils {
     private static void logWarnMessagesForIneffectiveValidations(Set<String> setValidations, Schema schema, Set<String> effectiveValidations) {
         setValidations.removeAll(effectiveValidations);
         setValidations.stream().forEach(validation -> {
-            LOGGER.warn("Validation '" + validation + "' has no effect on schema '" + schema.getType() +"'. Ignoring!");
+            LOGGER.warn("Validation '" + validation + "' has no effect on schema '" + getType(schema) +"'. Ignoring!");
         });
     }
 
@@ -2139,7 +2120,11 @@ public class ModelUtils {
         }
 
         if (schema instanceof JsonSchema) {
-            return String.valueOf(schema.getTypes().iterator().next());
+            if (schema.getTypes() != null) {
+                return String.valueOf(schema.getTypes().iterator().next());
+            } else {
+                return null;
+            }
         } else {
             return schema.getType();
         }

modules/openapi-generator/src/test/resources/3_1/java/petstore.yaml

@@ -969,3 +969,15 @@ components:
         - Code 1
         - Code 2
         - Code 3
+    SimpleModelWithArrayProperty:
+      type: object
+      required:
+        - arrayOfStrings
+      properties:
+        arrayOfStrings:
+          type: array
+          items:
+            type: string
+    AllOfSimpleModel:
+      allOf:
+        - $ref: '#/components/schemas/SimpleModelWithArrayProperty'

samples/client/petstore/java/okhttp-gson-3.1/.openapi-generator/FILES

@@ -5,6 +5,7 @@ README.md
 api/openapi.yaml
 build.gradle
 build.sbt
+docs/AllOfSimpleModel.md
 docs/Animal.md
 docs/AnyTypeTest.md
 docs/ArrayOfSameRef.md
@@ -21,6 +22,7 @@ docs/OneOfStringOrInt.md
 docs/Order.md
 docs/Pet.md
 docs/PetApi.md
+docs/SimpleModelWithArrayProperty.md
 docs/StoreApi.md
 docs/StringOrInt.md
 docs/Tag.md
@@ -61,6 +63,7 @@ src/main/java/org/openapitools/client/auth/OAuthFlow.java
 src/main/java/org/openapitools/client/auth/OAuthOkHttpClient.java
 src/main/java/org/openapitools/client/auth/RetryingOAuth.java
 src/main/java/org/openapitools/client/model/AbstractOpenApiSchema.java
+src/main/java/org/openapitools/client/model/AllOfSimpleModel.java
 src/main/java/org/openapitools/client/model/Animal.java
 src/main/java/org/openapitools/client/model/AnyTypeTest.java
 src/main/java/org/openapitools/client/model/ArrayOfSameRef.java
@@ -75,6 +78,7 @@ src/main/java/org/openapitools/client/model/ModelApiResponse.java
 src/main/java/org/openapitools/client/model/OneOfStringOrInt.java
 src/main/java/org/openapitools/client/model/Order.java
 src/main/java/org/openapitools/client/model/Pet.java
+src/main/java/org/openapitools/client/model/SimpleModelWithArrayProperty.java
 src/main/java/org/openapitools/client/model/StringOrInt.java
 src/main/java/org/openapitools/client/model/Tag.java
 src/main/java/org/openapitools/client/model/User.java

samples/client/petstore/java/okhttp-gson-3.1/README.md

@@ -144,6 +144,7 @@ Class | Method | HTTP request | Description
 
 ## Documentation for Models
 
+ - [AllOfSimpleModel](docs/AllOfSimpleModel.md)
  - [Animal](docs/Animal.md)
  - [AnyTypeTest](docs/AnyTypeTest.md)
  - [ArrayOfSameRef](docs/ArrayOfSameRef.md)
@@ -158,6 +159,7 @@ Class | Method | HTTP request | Description
  - [OneOfStringOrInt](docs/OneOfStringOrInt.md)
  - [Order](docs/Order.md)
  - [Pet](docs/Pet.md)
+ - [SimpleModelWithArrayProperty](docs/SimpleModelWithArrayProperty.md)
  - [StringOrInt](docs/StringOrInt.md)
  - [Tag](docs/Tag.md)
  - [User](docs/User.md)

samples/client/petstore/java/okhttp-gson-3.1/api/openapi.yaml

@@ -1063,6 +1063,17 @@ components:
       - Code 2
       - Code 3
       type: string
+    SimpleModelWithArrayProperty:
+      properties:
+        arrayOfStrings:
+          items:
+            type: string
+          type: array
+      required:
+      - arrayOfStrings
+    AllOfSimpleModel:
+      allOf:
+      - $ref: '#/components/schemas/SimpleModelWithArrayProperty'
     updatePetWithForm_request:
       properties:
         name:

samples/client/petstore/java/okhttp-gson-3.1/docs/AllOfSimpleModel.md

@@ -0,0 +1,13 @@
+
+
+# AllOfSimpleModel
+
+
+## Properties
+
+| Name | Type | Description | Notes |
+|------------ | ------------- | ------------- | -------------|
+|**arrayOfStrings** | **List<String>** |  |  |
+
+
+

samples/client/petstore/java/okhttp-gson-3.1/docs/SimpleModelWithArrayProperty.md

@@ -0,0 +1,13 @@
+
+
+# SimpleModelWithArrayProperty
+
+
+## Properties
+
+| Name | Type | Description | Notes |
+|------------ | ------------- | ------------- | -------------|
+|**arrayOfStrings** | **List<String>** |  |  |
+
+
+

samples/client/petstore/java/okhttp-gson-3.1/src/main/java/org/openapitools/client/JSON.java

@@ -129,6 +129,7 @@ public class JSON {
         gsonBuilder.registerTypeAdapter(OffsetDateTime.class, offsetDateTimeTypeAdapter);
         gsonBuilder.registerTypeAdapter(LocalDate.class, localDateTypeAdapter);
         gsonBuilder.registerTypeAdapter(byte[].class, byteArrayAdapter);
+        gsonBuilder.registerTypeAdapterFactory(new org.openapitools.client.model.AllOfSimpleModel.CustomTypeAdapterFactory());
         gsonBuilder.registerTypeAdapterFactory(new org.openapitools.client.model.AnyTypeTest.CustomTypeAdapterFactory());
         gsonBuilder.registerTypeAdapterFactory(new org.openapitools.client.model.ArrayOfSameRef.CustomTypeAdapterFactory());
         gsonBuilder.registerTypeAdapterFactory(new org.openapitools.client.model.Cat.CustomTypeAdapterFactory());
@@ -141,6 +142,7 @@ public class JSON {
         gsonBuilder.registerTypeAdapterFactory(new org.openapitools.client.model.OneOfStringOrInt.CustomTypeAdapterFactory());
         gsonBuilder.registerTypeAdapterFactory(new org.openapitools.client.model.Order.CustomTypeAdapterFactory());
         gsonBuilder.registerTypeAdapterFactory(new org.openapitools.client.model.Pet.CustomTypeAdapterFactory());
+        gsonBuilder.registerTypeAdapterFactory(new org.openapitools.client.model.SimpleModelWithArrayProperty.CustomTypeAdapterFactory());
         gsonBuilder.registerTypeAdapterFactory(new org.openapitools.client.model.StringOrInt.CustomTypeAdapterFactory());
         gsonBuilder.registerTypeAdapterFactory(new org.openapitools.client.model.Tag.CustomTypeAdapterFactory());
         gsonBuilder.registerTypeAdapterFactory(new org.openapitools.client.model.User.CustomTypeAdapterFactory());

samples/client/petstore/java/okhttp-gson-3.1/src/main/java/org/openapitools/client/model/AllOfSimpleModel.java

@@ -0,0 +1,308 @@
+/*
+ * OpenAPI Petstore
+ * This is a sample server Petstore server. For this sample, you can use the api key `special-key` to test the authorization filters.
+ *
+ * The version of the OpenAPI document: 1.0.0
+ * 
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+package org.openapitools.client.model;
+
+import java.util.Objects;
+import com.google.gson.TypeAdapter;
+import com.google.gson.annotations.JsonAdapter;
+import com.google.gson.annotations.SerializedName;
+import com.google.gson.stream.JsonReader;
+import com.google.gson.stream.JsonWriter;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+import com.google.gson.Gson;
+import com.google.gson.GsonBuilder;
+import com.google.gson.JsonArray;
+import com.google.gson.JsonDeserializationContext;
+import com.google.gson.JsonDeserializer;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
+import com.google.gson.JsonParseException;
+import com.google.gson.TypeAdapterFactory;
+import com.google.gson.reflect.TypeToken;
+import com.google.gson.TypeAdapter;
+import com.google.gson.stream.JsonReader;
+import com.google.gson.stream.JsonWriter;
+import java.io.IOException;
+
+import java.lang.reflect.Type;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+import org.openapitools.client.JSON;
+
+/**
+ * AllOfSimpleModel
+ */
+@javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen", comments = "Generator version: 7.6.0-SNAPSHOT")
+public class AllOfSimpleModel {
+  public static final String SERIALIZED_NAME_ARRAY_OF_STRINGS = "arrayOfStrings";
+  @SerializedName(SERIALIZED_NAME_ARRAY_OF_STRINGS)
+  private List<String> arrayOfStrings = new ArrayList<>();
+
+  public AllOfSimpleModel() {
+  }
+
+  public AllOfSimpleModel arrayOfStrings(List<String> arrayOfStrings) {
+    this.arrayOfStrings = arrayOfStrings;
+    return this;
+  }
+
+  public AllOfSimpleModel addArrayOfStringsItem(String arrayOfStringsItem) {
+    if (this.arrayOfStrings == null) {
+      this.arrayOfStrings = new ArrayList<>();
+    }
+    this.arrayOfStrings.add(arrayOfStringsItem);
+    return this;
+  }
+
+   /**
+   * Get arrayOfStrings
+   * @return arrayOfStrings
+  **/
+  @javax.annotation.Nonnull
+  public List<String> getArrayOfStrings() {
+    return arrayOfStrings;
+  }
+
+  public void setArrayOfStrings(List<String> arrayOfStrings) {
+    this.arrayOfStrings = arrayOfStrings;
+  }
+
+  /**
+   * A container for additional, undeclared properties.
+   * This is a holder for any undeclared properties as specified with
+   * the 'additionalProperties' keyword in the OAS document.
+   */
+  private Map<String, Object> additionalProperties;
+
+  /**
+   * Set the additional (undeclared) property with the specified name and value.
+   * If the property does not already exist, create it otherwise replace it.
+   *
+   * @param key name of the property
+   * @param value value of the property
+   * @return the AllOfSimpleModel instance itself
+   */
+  public AllOfSimpleModel putAdditionalProperty(String key, Object value) {
+    if (this.additionalProperties == null) {
+        this.additionalProperties = new HashMap<String, Object>();
+    }
+    this.additionalProperties.put(key, value);
+    return this;
+  }
+
+  /**
+   * Return the additional (undeclared) property.
+   *
+   * @return a map of objects
+   */
+  public Map<String, Object> getAdditionalProperties() {
+    return additionalProperties;
+  }
+
+  /**
+   * Return the additional (undeclared) property with the specified name.
+   *
+   * @param key name of the property
+   * @return an object
+   */
+  public Object getAdditionalProperty(String key) {
+    if (this.additionalProperties == null) {
+        return null;
+    }
+    return this.additionalProperties.get(key);
+  }
+
+
+  @Override
+  public boolean equals(Object o) {
+    if (this == o) {
+      return true;
+    }
+    if (o == null || getClass() != o.getClass()) {
+      return false;
+    }
+    AllOfSimpleModel allOfSimpleModel = (AllOfSimpleModel) o;
+    return Objects.equals(this.arrayOfStrings, allOfSimpleModel.arrayOfStrings)&&
+        Objects.equals(this.additionalProperties, allOfSimpleModel.additionalProperties);
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(arrayOfStrings, additionalProperties);
+  }
+
+  @Override
+  public String toString() {
+    StringBuilder sb = new StringBuilder();
+    sb.append("class AllOfSimpleModel {\n");
+    sb.append("    arrayOfStrings: ").append(toIndentedString(arrayOfStrings)).append("\n");
+    sb.append("    additionalProperties: ").append(toIndentedString(additionalProperties)).append("\n");
+    sb.append("}");
+    return sb.toString();
+  }
+
+  /**
+   * Convert the given object to string with each line indented by 4 spaces
+   * (except the first line).
+   */
+  private String toIndentedString(Object o) {
+    if (o == null) {
+      return "null";
+    }
+    return o.toString().replace("\n", "\n    ");
+  }
+
+
+  public static HashSet<String> openapiFields;
+  public static HashSet<String> openapiRequiredFields;
+
+  static {
+    // a set of all properties/fields (JSON key names)
+    openapiFields = new HashSet<String>();
+    openapiFields.add("arrayOfStrings");
+
+    // a set of required properties/fields (JSON key names)
+    openapiRequiredFields = new HashSet<String>();
+    openapiRequiredFields.add("arrayOfStrings");
+  }
+
+ /**
+  * Validates the JSON Element and throws an exception if issues found
+  *
+  * @param jsonElement JSON Element
+  * @throws IOException if the JSON Element is invalid with respect to AllOfSimpleModel
+  */
+  public static void validateJsonElement(JsonElement jsonElement) throws IOException {
+      if (jsonElement == null) {
+        if (!AllOfSimpleModel.openapiRequiredFields.isEmpty()) { // has required fields but JSON element is null
+          throw new IllegalArgumentException(String.format("The required field(s) %s in AllOfSimpleModel is not found in the empty JSON string", AllOfSimpleModel.openapiRequiredFields.toString()));
+        }
+      }
+
+      // check to make sure all required properties/fields are present in the JSON string
+      for (String requiredField : AllOfSimpleModel.openapiRequiredFields) {
+        if (jsonElement.getAsJsonObject().get(requiredField) == null) {
+          throw new IllegalArgumentException(String.format("The required field `%s` is not found in the JSON string: %s", requiredField, jsonElement.toString()));
+        }
+      }
+        JsonObject jsonObj = jsonElement.getAsJsonObject();
+      // ensure the required json array is present
+      if (jsonObj.get("arrayOfStrings") == null) {
+        throw new IllegalArgumentException("Expected the field `linkedContent` to be an array in the JSON string but got `null`");
+      } else if (!jsonObj.get("arrayOfStrings").isJsonArray()) {
+        throw new IllegalArgumentException(String.format("Expected the field `arrayOfStrings` to be an array in the JSON string but got `%s`", jsonObj.get("arrayOfStrings").toString()));
+      }
+  }
+
+  public static class CustomTypeAdapterFactory implements TypeAdapterFactory {
+    @SuppressWarnings("unchecked")
+    @Override
+    public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> type) {
+       if (!AllOfSimpleModel.class.isAssignableFrom(type.getRawType())) {
+         return null; // this class only serializes 'AllOfSimpleModel' and its subtypes
+       }
+       final TypeAdapter<JsonElement> elementAdapter = gson.getAdapter(JsonElement.class);
+       final TypeAdapter<AllOfSimpleModel> thisAdapter
+                        = gson.getDelegateAdapter(this, TypeToken.get(AllOfSimpleModel.class));
+
+       return (TypeAdapter<T>) new TypeAdapter<AllOfSimpleModel>() {
+           @Override
+           public void write(JsonWriter out, AllOfSimpleModel value) throws IOException {
+             JsonObject obj = thisAdapter.toJsonTree(value).getAsJsonObject();
+             obj.remove("additionalProperties");
+             // serialize additional properties
+             if (value.getAdditionalProperties() != null) {
+               for (Map.Entry<String, Object> entry : value.getAdditionalProperties().entrySet()) {
+                 if (entry.getValue() instanceof String)
+                   obj.addProperty(entry.getKey(), (String) entry.getValue());
+                 else if (entry.getValue() instanceof Number)
+                   obj.addProperty(entry.getKey(), (Number) entry.getValue());
+                 else if (entry.getValue() instanceof Boolean)
+                   obj.addProperty(entry.getKey(), (Boolean) entry.getValue());
+                 else if (entry.getValue() instanceof Character)
+                   obj.addProperty(entry.getKey(), (Character) entry.getValue());
+                 else {
+                   JsonElement jsonElement = gson.toJsonTree(entry.getValue());
+                   if (jsonElement.isJsonArray()) {
+                     obj.add(entry.getKey(), jsonElement.getAsJsonArray());
+                   } else {
+                     obj.add(entry.getKey(), jsonElement.getAsJsonObject());
+                   }
+                 }
+               }
+             }
+             elementAdapter.write(out, obj);
+           }
+
+           @Override
+           public AllOfSimpleModel read(JsonReader in) throws IOException {
+             JsonElement jsonElement = elementAdapter.read(in);
+             validateJsonElement(jsonElement);
+             JsonObject jsonObj = jsonElement.getAsJsonObject();
+             // store additional fields in the deserialized instance
+             AllOfSimpleModel instance = thisAdapter.fromJsonTree(jsonObj);
+             for (Map.Entry<String, JsonElement> entry : jsonObj.entrySet()) {
+               if (!openapiFields.contains(entry.getKey())) {
+                 if (entry.getValue().isJsonPrimitive()) { // primitive type
+                   if (entry.getValue().getAsJsonPrimitive().isString())
+                     instance.putAdditionalProperty(entry.getKey(), entry.getValue().getAsString());
+                   else if (entry.getValue().getAsJsonPrimitive().isNumber())
+                     instance.putAdditionalProperty(entry.getKey(), entry.getValue().getAsNumber());
+                   else if (entry.getValue().getAsJsonPrimitive().isBoolean())
+                     instance.putAdditionalProperty(entry.getKey(), entry.getValue().getAsBoolean());
+                   else
+                     throw new IllegalArgumentException(String.format("The field `%s` has unknown primitive type. Value: %s", entry.getKey(), entry.getValue().toString()));
+                 } else if (entry.getValue().isJsonArray()) {
+                     instance.putAdditionalProperty(entry.getKey(), gson.fromJson(entry.getValue(), List.class));
+                 } else { // JSON object
+                     instance.putAdditionalProperty(entry.getKey(), gson.fromJson(entry.getValue(), HashMap.class));
+                 }
+               }
+             }
+             return instance;
+           }
+
+       }.nullSafe();
+    }
+  }
+
+ /**
+  * Create an instance of AllOfSimpleModel given an JSON string
+  *
+  * @param jsonString JSON string
+  * @return An instance of AllOfSimpleModel
+  * @throws IOException if the JSON string is invalid with respect to AllOfSimpleModel
+  */
+  public static AllOfSimpleModel fromJson(String jsonString) throws IOException {
+    return JSON.getGson().fromJson(jsonString, AllOfSimpleModel.class);
+  }
+
+ /**
+  * Convert an instance of AllOfSimpleModel to an JSON string
+  *
+  * @return JSON string
+  */
+  public String toJson() {
+    return JSON.getGson().toJson(this);
+  }
+}
+

samples/client/petstore/java/okhttp-gson-3.1/src/main/java/org/openapitools/client/model/SimpleModelWithArrayProperty.java

@@ -0,0 +1,308 @@
+/*
+ * OpenAPI Petstore
+ * This is a sample server Petstore server. For this sample, you can use the api key `special-key` to test the authorization filters.
+ *
+ * The version of the OpenAPI document: 1.0.0
+ * 
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+package org.openapitools.client.model;
+
+import java.util.Objects;
+import com.google.gson.TypeAdapter;
+import com.google.gson.annotations.JsonAdapter;
+import com.google.gson.annotations.SerializedName;
+import com.google.gson.stream.JsonReader;
+import com.google.gson.stream.JsonWriter;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+import com.google.gson.Gson;
+import com.google.gson.GsonBuilder;
+import com.google.gson.JsonArray;
+import com.google.gson.JsonDeserializationContext;
+import com.google.gson.JsonDeserializer;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
+import com.google.gson.JsonParseException;
+import com.google.gson.TypeAdapterFactory;
+import com.google.gson.reflect.TypeToken;
+import com.google.gson.TypeAdapter;
+import com.google.gson.stream.JsonReader;
+import com.google.gson.stream.JsonWriter;
+import java.io.IOException;
+
+import java.lang.reflect.Type;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+import org.openapitools.client.JSON;
+
+/**
+ * SimpleModelWithArrayProperty
+ */
+@javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen", comments = "Generator version: 7.6.0-SNAPSHOT")
+public class SimpleModelWithArrayProperty {
+  public static final String SERIALIZED_NAME_ARRAY_OF_STRINGS = "arrayOfStrings";
+  @SerializedName(SERIALIZED_NAME_ARRAY_OF_STRINGS)
+  private List<String> arrayOfStrings = new ArrayList<>();
+
+  public SimpleModelWithArrayProperty() {
+  }
+
+  public SimpleModelWithArrayProperty arrayOfStrings(List<String> arrayOfStrings) {
+    this.arrayOfStrings = arrayOfStrings;
+    return this;
+  }
+
+  public SimpleModelWithArrayProperty addArrayOfStringsItem(String arrayOfStringsItem) {
+    if (this.arrayOfStrings == null) {
+      this.arrayOfStrings = new ArrayList<>();
+    }
+    this.arrayOfStrings.add(arrayOfStringsItem);
+    return this;
+  }
+
+   /**
+   * Get arrayOfStrings
+   * @return arrayOfStrings
+  **/
+  @javax.annotation.Nonnull
+  public List<String> getArrayOfStrings() {
+    return arrayOfStrings;
+  }
+
+  public void setArrayOfStrings(List<String> arrayOfStrings) {
+    this.arrayOfStrings = arrayOfStrings;
+  }
+
+  /**
+   * A container for additional, undeclared properties.
+   * This is a holder for any undeclared properties as specified with
+   * the 'additionalProperties' keyword in the OAS document.
+   */
+  private Map<String, Object> additionalProperties;
+
+  /**
+   * Set the additional (undeclared) property with the specified name and value.
+   * If the property does not already exist, create it otherwise replace it.
+   *
+   * @param key name of the property
+   * @param value value of the property
+   * @return the SimpleModelWithArrayProperty instance itself
+   */
+  public SimpleModelWithArrayProperty putAdditionalProperty(String key, Object value) {
+    if (this.additionalProperties == null) {
+        this.additionalProperties = new HashMap<String, Object>();
+    }
+    this.additionalProperties.put(key, value);
+    return this;
+  }
+
+  /**
+   * Return the additional (undeclared) property.
+   *
+   * @return a map of objects
+   */
+  public Map<String, Object> getAdditionalProperties() {
+    return additionalProperties;
+  }
+
+  /**
+   * Return the additional (undeclared) property with the specified name.
+   *
+   * @param key name of the property
+   * @return an object
+   */
+  public Object getAdditionalProperty(String key) {
+    if (this.additionalProperties == null) {
+        return null;
+    }
+    return this.additionalProperties.get(key);
+  }
+
+
+  @Override
+  public boolean equals(Object o) {
+    if (this == o) {
+      return true;
+    }
+    if (o == null || getClass() != o.getClass()) {
+      return false;
+    }
+    SimpleModelWithArrayProperty simpleModelWithArrayProperty = (SimpleModelWithArrayProperty) o;
+    return Objects.equals(this.arrayOfStrings, simpleModelWithArrayProperty.arrayOfStrings)&&
+        Objects.equals(this.additionalProperties, simpleModelWithArrayProperty.additionalProperties);
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(arrayOfStrings, additionalProperties);
+  }
+
+  @Override
+  public String toString() {
+    StringBuilder sb = new StringBuilder();
+    sb.append("class SimpleModelWithArrayProperty {\n");
+    sb.append("    arrayOfStrings: ").append(toIndentedString(arrayOfStrings)).append("\n");
+    sb.append("    additionalProperties: ").append(toIndentedString(additionalProperties)).append("\n");
+    sb.append("}");
+    return sb.toString();
+  }
+
+  /**
+   * Convert the given object to string with each line indented by 4 spaces
+   * (except the first line).
+   */
+  private String toIndentedString(Object o) {
+    if (o == null) {
+      return "null";
+    }
+    return o.toString().replace("\n", "\n    ");
+  }
+
+
+  public static HashSet<String> openapiFields;
+  public static HashSet<String> openapiRequiredFields;
+
+  static {
+    // a set of all properties/fields (JSON key names)
+    openapiFields = new HashSet<String>();
+    openapiFields.add("arrayOfStrings");
+
+    // a set of required properties/fields (JSON key names)
+    openapiRequiredFields = new HashSet<String>();
+    openapiRequiredFields.add("arrayOfStrings");
+  }
+
+ /**
+  * Validates the JSON Element and throws an exception if issues found
+  *
+  * @param jsonElement JSON Element
+  * @throws IOException if the JSON Element is invalid with respect to SimpleModelWithArrayProperty
+  */
+  public static void validateJsonElement(JsonElement jsonElement) throws IOException {
+      if (jsonElement == null) {
+        if (!SimpleModelWithArrayProperty.openapiRequiredFields.isEmpty()) { // has required fields but JSON element is null
+          throw new IllegalArgumentException(String.format("The required field(s) %s in SimpleModelWithArrayProperty is not found in the empty JSON string", SimpleModelWithArrayProperty.openapiRequiredFields.toString()));
+        }
+      }
+
+      // check to make sure all required properties/fields are present in the JSON string
+      for (String requiredField : SimpleModelWithArrayProperty.openapiRequiredFields) {
+        if (jsonElement.getAsJsonObject().get(requiredField) == null) {
+          throw new IllegalArgumentException(String.format("The required field `%s` is not found in the JSON string: %s", requiredField, jsonElement.toString()));
+        }
+      }
+        JsonObject jsonObj = jsonElement.getAsJsonObject();
+      // ensure the required json array is present
+      if (jsonObj.get("arrayOfStrings") == null) {
+        throw new IllegalArgumentException("Expected the field `linkedContent` to be an array in the JSON string but got `null`");
+      } else if (!jsonObj.get("arrayOfStrings").isJsonArray()) {
+        throw new IllegalArgumentException(String.format("Expected the field `arrayOfStrings` to be an array in the JSON string but got `%s`", jsonObj.get("arrayOfStrings").toString()));
+      }
+  }
+
+  public static class CustomTypeAdapterFactory implements TypeAdapterFactory {
+    @SuppressWarnings("unchecked")
+    @Override
+    public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> type) {
+       if (!SimpleModelWithArrayProperty.class.isAssignableFrom(type.getRawType())) {
+         return null; // this class only serializes 'SimpleModelWithArrayProperty' and its subtypes
+       }
+       final TypeAdapter<JsonElement> elementAdapter = gson.getAdapter(JsonElement.class);
+       final TypeAdapter<SimpleModelWithArrayProperty> thisAdapter
+                        = gson.getDelegateAdapter(this, TypeToken.get(SimpleModelWithArrayProperty.class));
+
+       return (TypeAdapter<T>) new TypeAdapter<SimpleModelWithArrayProperty>() {
+           @Override
+           public void write(JsonWriter out, SimpleModelWithArrayProperty value) throws IOException {
+             JsonObject obj = thisAdapter.toJsonTree(value).getAsJsonObject();
+             obj.remove("additionalProperties");
+             // serialize additional properties
+             if (value.getAdditionalProperties() != null) {
+               for (Map.Entry<String, Object> entry : value.getAdditionalProperties().entrySet()) {
+                 if (entry.getValue() instanceof String)
+                   obj.addProperty(entry.getKey(), (String) entry.getValue());
+                 else if (entry.getValue() instanceof Number)
+                   obj.addProperty(entry.getKey(), (Number) entry.getValue());
+                 else if (entry.getValue() instanceof Boolean)
+                   obj.addProperty(entry.getKey(), (Boolean) entry.getValue());
+                 else if (entry.getValue() instanceof Character)
+                   obj.addProperty(entry.getKey(), (Character) entry.getValue());
+                 else {
+                   JsonElement jsonElement = gson.toJsonTree(entry.getValue());
+                   if (jsonElement.isJsonArray()) {
+                     obj.add(entry.getKey(), jsonElement.getAsJsonArray());
+                   } else {
+                     obj.add(entry.getKey(), jsonElement.getAsJsonObject());
+                   }
+                 }
+               }
+             }
+             elementAdapter.write(out, obj);
+           }
+
+           @Override
+           public SimpleModelWithArrayProperty read(JsonReader in) throws IOException {
+             JsonElement jsonElement = elementAdapter.read(in);
+             validateJsonElement(jsonElement);
+             JsonObject jsonObj = jsonElement.getAsJsonObject();
+             // store additional fields in the deserialized instance
+             SimpleModelWithArrayProperty instance = thisAdapter.fromJsonTree(jsonObj);
+             for (Map.Entry<String, JsonElement> entry : jsonObj.entrySet()) {
+               if (!openapiFields.contains(entry.getKey())) {
+                 if (entry.getValue().isJsonPrimitive()) { // primitive type
+                   if (entry.getValue().getAsJsonPrimitive().isString())
+                     instance.putAdditionalProperty(entry.getKey(), entry.getValue().getAsString());
+                   else if (entry.getValue().getAsJsonPrimitive().isNumber())
+                     instance.putAdditionalProperty(entry.getKey(), entry.getValue().getAsNumber());
+                   else if (entry.getValue().getAsJsonPrimitive().isBoolean())
+                     instance.putAdditionalProperty(entry.getKey(), entry.getValue().getAsBoolean());
+                   else
+                     throw new IllegalArgumentException(String.format("The field `%s` has unknown primitive type. Value: %s", entry.getKey(), entry.getValue().toString()));
+                 } else if (entry.getValue().isJsonArray()) {
+                     instance.putAdditionalProperty(entry.getKey(), gson.fromJson(entry.getValue(), List.class));
+                 } else { // JSON object
+                     instance.putAdditionalProperty(entry.getKey(), gson.fromJson(entry.getValue(), HashMap.class));
+                 }
+               }
+             }
+             return instance;
+           }
+
+       }.nullSafe();
+    }
+  }
+
+ /**
+  * Create an instance of SimpleModelWithArrayProperty given an JSON string
+  *
+  * @param jsonString JSON string
+  * @return An instance of SimpleModelWithArrayProperty
+  * @throws IOException if the JSON string is invalid with respect to SimpleModelWithArrayProperty
+  */
+  public static SimpleModelWithArrayProperty fromJson(String jsonString) throws IOException {
+    return JSON.getGson().fromJson(jsonString, SimpleModelWithArrayProperty.class);
+  }
+
+ /**
+  * Convert an instance of SimpleModelWithArrayProperty to an JSON string
+  *
+  * @return JSON string
+  */
+  public String toJson() {
+    return JSON.getGson().toJson(this);
+  }
+}
+

samples/client/petstore/java/okhttp-gson-3.1/src/test/java/org/openapitools/client/model/AllOfSimpleModelTest.java

@@ -0,0 +1,50 @@
+/*
+ * OpenAPI Petstore
+ * This is a sample server Petstore server. For this sample, you can use the api key `special-key` to test the authorization filters.
+ *
+ * The version of the OpenAPI document: 1.0.0
+ * 
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+package org.openapitools.client.model;
+
+import com.google.gson.TypeAdapter;
+import com.google.gson.annotations.JsonAdapter;
+import com.google.gson.annotations.SerializedName;
+import com.google.gson.stream.JsonReader;
+import com.google.gson.stream.JsonWriter;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+import org.junit.jupiter.api.Disabled;
+import org.junit.jupiter.api.Test;
+
+/**
+ * Model tests for AllOfSimpleModel
+ */
+public class AllOfSimpleModelTest {
+    private final AllOfSimpleModel model = new AllOfSimpleModel();
+
+    /**
+     * Model tests for AllOfSimpleModel
+     */
+    @Test
+    public void testAllOfSimpleModel() {
+        // TODO: test AllOfSimpleModel
+    }
+
+    /**
+     * Test the property 'arrayOfStrings'
+     */
+    @Test
+    public void arrayOfStringsTest() {
+        // TODO: test arrayOfStrings
+    }
+
+}

samples/client/petstore/java/okhttp-gson-3.1/src/test/java/org/openapitools/client/model/SimpleModelWithArrayPropertyTest.java

@@ -0,0 +1,50 @@
+/*
+ * OpenAPI Petstore
+ * This is a sample server Petstore server. For this sample, you can use the api key `special-key` to test the authorization filters.
+ *
+ * The version of the OpenAPI document: 1.0.0
+ * 
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+package org.openapitools.client.model;
+
+import com.google.gson.TypeAdapter;
+import com.google.gson.annotations.JsonAdapter;
+import com.google.gson.annotations.SerializedName;
+import com.google.gson.stream.JsonReader;
+import com.google.gson.stream.JsonWriter;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+import org.junit.jupiter.api.Disabled;
+import org.junit.jupiter.api.Test;
+
+/**
+ * Model tests for SimpleModelWithArrayProperty
+ */
+public class SimpleModelWithArrayPropertyTest {
+    private final SimpleModelWithArrayProperty model = new SimpleModelWithArrayProperty();
+
+    /**
+     * Model tests for SimpleModelWithArrayProperty
+     */
+    @Test
+    public void testSimpleModelWithArrayProperty() {
+        // TODO: test SimpleModelWithArrayProperty
+    }
+
+    /**
+     * Test the property 'arrayOfStrings'
+     */
+    @Test
+    public void arrayOfStringsTest() {
+        // TODO: test arrayOfStrings
+    }
+
+}