/* * Copyright (c) 2022, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. * */ import java.io.File; import java.net.URL; import java.net.URLClassLoader; import java.security.ProtectionDomain; public class ClassListWithCustomClassNoSource { private static byte[] helloBytes; private static final String HELLO = "Hello"; static class CL extends ClassLoader { private ProtectionDomain pd; public CL(String name, ClassLoader parent, ProtectionDomain protD) { super(name, parent); pd = protD; } @Override protected Class findClass(String name) throws ClassNotFoundException { if (pd == null) { pd = new ProtectionDomain(null, null); } return defineClass(name, helloBytes, 0, helloBytes.length, pd); } } public static void main(String[] args) throws Exception { if (args.length != 1) { throw new RuntimeException("Invalid arg, Use 1, 2, or 3"); } ClassLoader thisLoader = ClassListWithCustomClassNoSource.class.getClassLoader(); helloBytes = thisLoader.getResourceAsStream(HELLO + ".class").readAllBytes(); switch(args[0]) { case "1": Class cls1 = (new CL("HelloLoader", null, null)).loadClass(HELLO); System.out.println(HELLO + " was successfully loaded by " + cls1.getClassLoader().getName()); break; case "2": ProtectionDomain p = ClassListWithCustomClassNoSource.class.getProtectionDomain(); Class cls2 = (new CL("HelloLoader", null, p)).loadClass(HELLO); System.out.println(HELLO + " was successfully loaded by " + cls2.getClassLoader().getName()); break; case "3": URL url = ClassListWithCustomClassNoSource.class.getProtectionDomain().getCodeSource().getLocation(); URLClassLoader urlLoader = new URLClassLoader("HelloClassLoader", new URL[] {url}, null); Class cls = urlLoader.loadClass(HELLO); if (cls != null) { System.out.println(HELLO + " was loaded by " + cls.getClassLoader().getName()); if (urlLoader != cls.getClassLoader()) { System.out.println(HELLO + " was not loaded by " + urlLoader.getName()); } } else { System.out.println(HELLO + " is not loaded"); } break; default: throw new RuntimeException("Should have one argument, 1, 2 or 3"); } } }