commit 03f81e780d4d78206eff672f71a3f168290dd6fe Author: Adam Heinrich Date: Sun Jun 14 10:04:53 2015 +0200 Initial commit diff --git a/LICENSE b/LICENSE new file mode 100644 index 0000000..06c59d7 --- /dev/null +++ b/LICENSE @@ -0,0 +1,22 @@ +The MIT License (MIT) + +Copyright (c) 2012 Adam Heinrich + +Permission is hereby granted, free of charge, to any person obtaining a copy +of this software and associated documentation files (the "Software"), to deal +in the Software without restriction, including without limitation the rights +to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +copies of the Software, and to permit persons to whom the Software is +furnished to do so, subject to the following conditions: + +The above copyright notice and this permission notice shall be included in all +copies or substantial portions of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE +SOFTWARE. + diff --git a/NativeUtils.java b/NativeUtils.java new file mode 100644 index 0000000..d8073d5 --- /dev/null +++ b/NativeUtils.java @@ -0,0 +1,118 @@ +/* + * Class NativeUtils is published under the The MIT License: + * + * Copyright (c) 2012 Adam Heinrich + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in all + * copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ +package cz.adamh.utils; + +import java.io.File; +import java.io.FileNotFoundException; +import java.io.FileOutputStream; +import java.io.IOException; +import java.io.InputStream; +import java.io.OutputStream; + +/** + * A simple library class which helps with loading dynamic libraries stored in the + * JAR archive. These libraries usualy contain implementation of some methods in + * native code (using JNI - Java Native Interface). + * + * @see http://adamheinrich.com/blog/2012/how-to-load-native-jni-library-from-jar + * @see https://github.com/adamheinrich/native-utils + * + */ +public class NativeUtils { + + /** + * Private constructor - this class will never be instanced + */ + private NativeUtils() { + } + + /** + * Loads library from current JAR archive + * + * The file from JAR is copied into system temporary directory and then loaded. The temporary file is deleted after exiting. + * Method uses String as filename because the pathname is "abstract", not system-dependent. + * + * @param filename The filename inside JAR as absolute path (beginning with '/'), e.g. /package/File.ext + * @throws IOException If temporary file creation or read/write operation fails + * @throws IllegalArgumentException If source file (param path) does not exist + * @throws IllegalArgumentException If the path is not absolute or if the filename is shorter than three characters (restriction of {@see File#createTempFile(java.lang.String, java.lang.String)}). + */ + public static void loadLibraryFromJar(String path) throws IOException { + + if (!path.startsWith("/")) { + throw new IllegalArgumentException("The path has to be absolute (start with '/')."); + } + + // Obtain filename from path + String[] parts = path.split("/"); + String filename = (parts.length > 1) ? parts[parts.length - 1] : null; + + // Split filename to prexif and suffix (extension) + String prefix = ""; + String suffix = null; + if (filename != null) { + parts = filename.split("\\.", 2); + prefix = parts[0]; + suffix = (parts.length > 1) ? "."+parts[parts.length - 1] : null; // Thanks, davs! :-) + } + + // Check if the filename is okay + if (filename == null || prefix.length() < 3) { + throw new IllegalArgumentException("The filename has to be at least 3 characters long."); + } + + // Prepare temporary file + File temp = File.createTempFile(prefix, suffix); + temp.deleteOnExit(); + + if (!temp.exists()) { + throw new FileNotFoundException("File " + temp.getAbsolutePath() + " does not exist."); + } + + // Prepare buffer for data copying + byte[] buffer = new byte[1024]; + int readBytes; + + // Open and check input stream + InputStream is = NativeUtils.class.getResourceAsStream(path); + if (is == null) { + throw new FileNotFoundException("File " + path + " was not found inside JAR."); + } + + // Open output stream and copy data between source file in JAR and the temporary file + OutputStream os = new FileOutputStream(temp); + try { + while ((readBytes = is.read(buffer)) != -1) { + os.write(buffer, 0, readBytes); + } + } finally { + // If read/write fails, close streams safely before throwing an exception + os.close(); + is.close(); + } + + // Finally, load the library + System.load(temp.getAbsolutePath()); + } +}