Javaで特定のパッケージに含まれるクラスの一覧を取得する

package jaxrsexample; import java.io.File; import java.io.IOException; import java.net.URL; import java.net.URLDecoder; import java.util.ArrayList; import java.util.Enumeration; import java.util.List; public class ClassListExample { @SuppressWarnings("rawtypes") public static void main(String[] args) throws Exception { for (Class klass : getClasses("jaxrsexample")) { System.out.println(klass.getName()); } } /** * Scans all classes accessible from the context class loader which belong * to the given package and subpackages. * * @param packageName * The base package * @return The classes * @throws ClassNotFoundException * @throws IOException */ @SuppressWarnings("rawtypes") private static List<Class> getClasses(String packageName) throws ClassNotFoundException, IOException { ClassLoader classLoader = Thread.currentThread() .getContextClassLoader(); assert classLoader != null; String path = packageName.replace('.', '/'); Enumeration<URL> resources = classLoader.getResources(path); List<File> dirs = new ArrayList<File>(); while (resources.hasMoreElements()) { URL resource = resources.nextElement(); String fileName = resource.getFile(); String fileNameDecoded = URLDecoder.decode(fileName, "UTF-8"); dirs.add(new File(fileNameDecoded)); } ArrayList<Class> classes = new ArrayList<Class>(); for (File directory : dirs) { classes.addAll(findClasses(directory, packageName)); } return classes; } /** * Recursive method used to find all classes in a given directory and * subdirs. * * @param directory * The base directory * @param packageName * The package name for classes found inside the base directory * @return The classes * @throws ClassNotFoundException */ @SuppressWarnings("rawtypes") private static List<Class> findClasses(File directory, String packageName) throws ClassNotFoundException { List<Class> classes = new ArrayList<Class>(); if (!directory.exists()) { return classes; } File[] files = directory.listFiles(); for (File file : files) { String fileName = file.getName(); if (file.isDirectory()) { assert !fileName.contains("."); classes.addAll(findClasses(file, packageName + "." + fileName)); } else if (fileName.endsWith(".class") && !fileName.contains("$")) { Class _class; try { _class = Class.forName(packageName + '.' + fileName.substring(0, fileName.length() - 6)); } catch (ExceptionInInitializerError e) { // happen, for example, in classes, which depend on // Spring to inject some beans, and which fail, // if dependency is not fulfilled _class = Class.forName( packageName + '.' + fileName.substring(0, fileName.length() - 6), false, Thread.currentThread().getContextClassLoader()); } classes.add(_class); } } return classes; } }