1 /* 2 * Copyright (c) 2020, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23 24 /* 25 * @test 26 * @summary Test the ability to safely unload a class that has an error 27 * with its designated nest host. The nest host class must resolve 28 * successfully but fail validation. This tests a specific, otherwise 29 * untested, code path in ResolutionErrorTable::free_entry. 30 * 31 * @library /runtime/testlibrary 32 * @compile TestNestHostErrorWithClassUnload.java 33 * Helper.java 34 * PackagedNestHost.java 35 * PackagedNestHost2.java 36 * @compile PackagedNestHost2Member.jcod 37 * 38 * @run main/othervm -Xlog:class+unload=trace TestNestHostErrorWithClassUnload 39 */ 40 41 // Test setup: 42 // PackagedNestHost.java defines P1.PackagedNestHost, which is referenced 43 // by P2.PackageNestHost2.Member 44 // PackagedNestHost2.java defines P2.PackagedNestHost2 and its nested Member 45 // class. 46 // PackagedNestHost2Member.jcod changes P2.PackagedNestHost.Member to claim 47 // it is in the nest of P1.PackagedNestHost. 48 // Helper.java is a helper class to run the test under the other classloader. 49 // A separate class is used to avoid confusion because if a public nested 50 // class were to be used, then the main test class would be loaded a second 51 // time in the other loader, and also subsequently unloaded. 52 // 53 // We load all classes into a new classloader and then try to call 54 // P2.PackagedNestHost.Member.m() which will be private at runtime. That will 55 // trigger nest host resolution and validation and the invocation will fail 56 // with IllegalAccessError. We then drop the classloader and invoke GC to force 57 // the unloading of the classes. Not all GC configurations are guaranteed to 58 // result in unloading, but that isn't essential for the test to succeed - we 59 // know that when unloading does occur we have tested the desired code path. 60 61 import java.lang.invoke.MethodHandle; 62 import java.lang.invoke.MethodHandles; 63 import java.lang.invoke.MethodType; 64 65 public class TestNestHostErrorWithClassUnload { 66 67 static final MethodType INVOKE_T = MethodType.methodType(void.class); 68 69 public static void main(String[] args) throws Throwable { 70 ClassLoader cl = ClassUnloadCommon.newClassLoader(); 71 Class<?> c = cl.loadClass("Helper"); 72 MethodHandle mh = MethodHandles.lookup().findStatic(c, "test", INVOKE_T); 73 mh.invoke(); 74 // now drop all references so we can trigger unloading 75 mh = null; 76 c = null; 77 cl = null; 78 ClassUnloadCommon.triggerUnloading(); 79 } 80 }