1 /* 2 * Copyright (c) 2019, Red Hat, Inc. 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 package gc.epsilon; 25 26 /** 27 * @test TestClasses 28 * @requires vm.gc.Epsilon 29 * @summary Epsilon is able to allocate a lot of classes 30 * 31 * @modules java.base/jdk.internal.org.objectweb.asm 32 * java.base/jdk.internal.misc 33 * 34 * @run main/othervm -Xmx128m -XX:MetaspaceSize=1m -XX:MaxMetaspaceSize=64m -XX:+UnlockExperimentalVMOptions -XX:+UseEpsilonGC -Xlog:gc -Xlog:gc+metaspace gc.epsilon.TestClasses 35 */ 36 37 import jdk.internal.org.objectweb.asm.ClassWriter; 38 import jdk.internal.org.objectweb.asm.Opcodes; 39 40 import java.util.*; 41 import java.io.*; 42 import java.nio.*; 43 import java.nio.file.*; 44 45 public class TestClasses { 46 47 static final int COUNT = 32*1024; 48 49 static volatile Object sink; 50 51 static class MyClassLoader extends ClassLoader { 52 public byte[] createClass(String name) { 53 ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_MAXS | ClassWriter.COMPUTE_FRAMES); 54 cw.visit(Opcodes.V1_8, Opcodes.ACC_PUBLIC | Opcodes.ACC_SUPER, name, null, "java/lang/Object", null); 55 return cw.toByteArray(); 56 } 57 58 public Class<?> loadClass(String name) throws ClassNotFoundException { 59 if (!name.startsWith("Dummy")) { 60 return super.loadClass(name); 61 } 62 byte[] cls = createClass(name); 63 return defineClass(name, cls, 0, cls.length, null); 64 } 65 } 66 67 public static void main(String[] args) throws Exception { 68 ClassLoader cl = new MyClassLoader(); 69 for (int c = 0; c < COUNT; c++) { 70 Class<?> clazz = Class.forName("Dummy" + c, true, cl); 71 if (clazz.getClassLoader() != cl) { 72 throw new IllegalStateException("Should have loaded by target loader"); 73 } 74 sink = c; 75 } 76 } 77 }