/* * Copyright (c) 2018, 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. */ /* * @test UnloadInterfaceTest * @requires vm.opt.final.ClassUnloading * @modules java.base/jdk.internal.misc * @library /test/lib * @compile test/Interface.java * @compile test/ImplementorClass.java * @build jdk.test.whitebox.WhiteBox * @run driver jdk.test.lib.helpers.ClassFileInstaller jdk.test.whitebox.WhiteBox * @run main/othervm -Xbootclasspath/a:. -Xmn8m -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -Xlog:class+unload=trace UnloadInterfaceTest */ import jdk.test.whitebox.WhiteBox; import test.Interface; import java.lang.ClassLoader; import jdk.test.lib.classloader.ClassUnloadCommon; /** * Test that verifies that class unloaded removes the implementor from its the interface that it implements * via logging. * [1.364s][info][class,unload] unloading class test.ImplementorClass 0x00000008000a2840 * [1.366s][trace][class,unload] unlinking class (subclass): test.ImplementorClass * [1.366s][trace][class,unload] unlinking class (implementor): test.ImplementorClass */ public class UnloadInterfaceTest { private static String className = "test.ImplementorClass"; private static String interfaceName = "test.Interface"; static class LoaderToUnload extends ClassLoader { ClassLoader myParent; public Class loadClass(String name) throws ClassNotFoundException { if (name.contains(className)) { System.out.println("className found " + className); byte[] data = ClassUnloadCommon.getClassData(name); return defineClass(name, data, 0, data.length); } else { return myParent.loadClass(name); } } public LoaderToUnload(ClassLoader parent) { super(); myParent = parent; } } public static void main(String... args) throws Exception { run(); } private static void run() throws Exception { final WhiteBox wb = WhiteBox.getWhiteBox(); ClassUnloadCommon.failIf(wb.isClassAlive(className), "is not expected to be alive yet"); // Load interface Class with one class loader. ClassLoader icl = ClassUnloadCommon.newClassLoader(); Class ic = icl.loadClass(interfaceName); ClassLoader cl = new LoaderToUnload(icl); Class c = cl.loadClass(className); Object o = c.newInstance(); ClassUnloadCommon.failIf(!wb.isClassAlive(className), "should be live here"); ClassUnloadCommon.failIf(!wb.isClassAlive(interfaceName), "should be live here"); cl = null; c = null; o = null; ClassUnloadCommon.triggerUnloading(); ClassUnloadCommon.failIf(wb.isClassAlive(className), "should have been unloaded"); ClassUnloadCommon.failIf(!wb.isClassAlive(interfaceName), "should be live here"); System.out.println("We still have Interface referenced" + ic); } }