Here you can find the source of getAllClassesInPackage(String packageName)
public static List<Class<?>> getAllClassesInPackage(String packageName) throws ClassNotFoundException, IOException
//package com.java2s; /*/*w w w . j ava 2 s. c o m*/ * [The "BSD licence"] * Copyright (c) 2012 Dandelion * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of Dandelion nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ import java.io.File; import java.io.IOException; import java.net.MalformedURLException; import java.net.URL; import java.net.URLDecoder; import java.util.ArrayList; import java.util.Enumeration; import java.util.List; import java.util.TreeSet; import java.util.zip.ZipEntry; import java.util.zip.ZipInputStream; public class Main { public static List<Class<?>> getAllClassesInPackage(String packageName) throws ClassNotFoundException, IOException { ClassLoader classLoader = Thread.currentThread().getContextClassLoader(); String path = packageName.replace('.', '/'); Enumeration<URL> resources = classLoader.getResources(path); List<String> dirs = new ArrayList<String>(); while (resources.hasMoreElements()) { URL resource = resources.nextElement(); dirs.add(URLDecoder.decode(resource.getFile(), "UTF-8")); } TreeSet<String> classes = new TreeSet<String>(); for (String directory : dirs) { classes.addAll(findClasses(directory, packageName)); } ArrayList<Class<?>> classList = new ArrayList<Class<?>>(); for (String clazz : classes) { classList.add(Class.forName(clazz)); } return classList; } private static TreeSet<String> findClasses(String path, String packageName) throws MalformedURLException, IOException { TreeSet<String> classes = new TreeSet<String>(); if (path.startsWith("file:") && path.contains("!")) { String[] split = path.split("!"); URL jar = new URL(split[0]); ZipInputStream zip = new ZipInputStream(jar.openStream()); ZipEntry entry; while ((entry = zip.getNextEntry()) != null) { if (entry.getName().endsWith(".class")) { String className = entry.getName().replaceAll("[$].*", "").replaceAll("[.]class", "") .replace('/', '.'); if (className.startsWith(packageName)) { classes.add(className); } } } } File dir = new File(path); if (!dir.exists()) { return classes; } File[] files = dir.listFiles(); for (File file : files) { if (file.isDirectory()) { classes.addAll(findClasses(file.getAbsolutePath(), packageName + "." + file.getName())); } else if (file.getName().endsWith(".class")) { // Build the class name with the package name and the file after // removing the .class extension String className = packageName + '.' + file.getName().substring(0, file.getName().length() - 6); classes.add(className); } } return classes; } }