1 /* 2 * Copyright (c) 2016, 2018, 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 * @bug 8151486 27 * @summary Call Class.forName() on the system classloader from a class loaded 28 * from a custom classloader. 29 * @library /test/lib 30 * @build jdk.test.lib.Utils JarUtils 31 * @build ClassForName ClassForNameLeak 32 * @run main/othervm/policy=test.policy -Djava.security.manager ClassForNameLeak 33 */ 34 35 import java.io.IOException; 36 import java.lang.ref.PhantomReference; 37 import java.lang.ref.Reference; 38 import java.lang.ref.ReferenceQueue; 39 import java.net.MalformedURLException; 40 import java.net.URL; 41 import java.net.URLClassLoader; 42 import java.nio.file.Path; 43 import java.nio.file.Paths; 44 import java.util.List; 45 import java.util.concurrent.Callable; 46 import java.util.concurrent.ExecutorService; 47 import java.util.concurrent.Executors; 48 import java.util.concurrent.Future; 49 import java.util.stream.Collectors; 50 import java.util.stream.Stream; 51 import jdk.test.lib.Utils; 52 53 /* 54 * Create .jar, load ClassForName from .jar using a URLClassLoader 55 */ 56 public class ClassForNameLeak { 57 private static final long TIMEOUT = (long)(5000.0 * Utils.TIMEOUT_FACTOR); 58 private static final int THREADS = 10; 59 private static final Path jarFilePath = Paths.get("cfn.jar"); 60 private static final ReferenceQueue<ClassLoader> rq = new ReferenceQueue<>(); 61 62 static class TestLoader { 63 private final PhantomReference<ClassLoader> ref; 64 TestLoader() { 65 this.ref = loadAndRun(); 66 } 67 68 // Use a new classloader to load the ClassForName class, then run its 69 // Runnable. 70 PhantomReference<ClassLoader> loadAndRun() { 71 try { 72 ClassLoader classLoader = 73 new URLClassLoader("LeakedClassLoader", 74 new URL[]{jarFilePath.toUri().toURL()}, 75 ClassLoader.getPlatformClassLoader()); 76 77 Class<?> loadClass = Class.forName("ClassForName", true, classLoader); 78 ((Runnable) loadClass.newInstance()).run(); 79 80 return new PhantomReference<>(classLoader, rq); 81 } catch (MalformedURLException|ReflectiveOperationException e) { 82 throw new RuntimeException(e); 83 } 84 } 85 86 PhantomReference<ClassLoader> getRef() { 87 return ref; 88 } 89 } 90 91 public static void main(String... args) throws Exception { 92 // create the JAR file 93 setup(); 94 95 // Make simultaneous calls to the test method, to stress things a bit 96 ExecutorService es = Executors.newFixedThreadPool(THREADS); 97 98 List<Callable<TestLoader>> callables = 99 Stream.generate(() -> { 100 Callable<TestLoader> cprcl = TestLoader::new; 101 return cprcl; 102 }).limit(THREADS).collect(Collectors.toList()); 103 104 List<Future<TestLoader>> futures = es.invokeAll(callables); 105 106 // Give the GC a chance to enqueue the PhantomReferences 107 for (int i = 0; i < 10; i++) { 108 System.gc(); 109 } 110 111 // Make sure all PhantomReferences to the leaked classloader are enqueued 112 for (int j = 0; j < futures.size(); j++) { 113 Reference rmRef = rq.remove(TIMEOUT); 114 if (rmRef == null) { 115 throw new RuntimeException("ClassLoader was never enqueued!"); 116 } else { 117 System.out.println("Enqueued " + rmRef); 118 } 119 } 120 es.shutdown(); 121 System.out.println("All ClassLoaders successfully enqueued"); 122 } 123 124 private static final String CLASSFILENAME = "ClassForName.class"; 125 private static void setup() throws IOException { 126 String testclasses = System.getProperty("test.classes", "."); 127 128 // Create a temporary .jar file containing ClassForName.class 129 Path testClassesDir = Paths.get(testclasses); 130 JarUtils.createJarFile(jarFilePath, testClassesDir, CLASSFILENAME); 131 } 132 }