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/*
* Copyright (c) 2016, 2018, 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
* @bug 8151486
* @summary Call Class.forName() on the system classloader from a class loaded
* from a custom classloader.
* @library /lib/testlibrary
* @build jdk.testlibrary.Utils JarUtils
* @build ClassForName ClassForNameLeak
* @run main/othervm/policy=test.policy -Djava.security.manager ClassForNameLeak
*/
import java.io.IOException;
import java.lang.ref.PhantomReference;
import java.lang.ref.Reference;
import java.lang.ref.ReferenceQueue;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLClassLoader;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.List;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.stream.Collectors;
import java.util.stream.Stream;
import jdk.testlibrary.Utils;
/*
* Create .jar, load ClassForName from .jar using a URLClassLoader
*/
public class ClassForNameLeak {
private static final long TIMEOUT = (long)(5000.0 * Utils.TIMEOUT_FACTOR);
private static final int THREADS = 10;
private static final Path jarFilePath = Paths.get("cfn.jar");
private static final ReferenceQueue<ClassLoader> rq = new ReferenceQueue<>();
static class TestLoader {
private final PhantomReference<ClassLoader> ref;
TestLoader() {
this.ref = loadAndRun();
}
// Use a new classloader to load the ClassForName class, then run its
// Runnable.
PhantomReference<ClassLoader> loadAndRun() {
try {
ClassLoader classLoader =
new URLClassLoader("LeakedClassLoader",
new URL[]{jarFilePath.toUri().toURL()},
ClassLoader.getPlatformClassLoader());
Class<?> loadClass = Class.forName("ClassForName", true, classLoader);
((Runnable) loadClass.newInstance()).run();
return new PhantomReference<>(classLoader, rq);
} catch (MalformedURLException|ReflectiveOperationException e) {
throw new RuntimeException(e);
}
}
PhantomReference<ClassLoader> getRef() {
return ref;
}
}
public static void main(String... args) throws Exception {
// create the JAR file
setup();
// Make simultaneous calls to the test method, to stress things a bit
ExecutorService es = Executors.newFixedThreadPool(THREADS);
List<Callable<TestLoader>> callables =
Stream.generate(() -> {
Callable<TestLoader> cprcl = TestLoader::new;
return cprcl;
}).limit(THREADS).collect(Collectors.toList());
List<Future<TestLoader>> futures = es.invokeAll(callables);
// Give the GC a chance to enqueue the PhantomReferences
for (int i = 0; i < 10; i++) {
System.gc();
}
// Make sure all PhantomReferences to the leaked classloader are enqueued
for (int j = 0; j < futures.size(); j++) {
Reference rmRef = rq.remove(TIMEOUT);
if (rmRef == null) {
throw new RuntimeException("ClassLoader was never enqueued!");
} else {
System.out.println("Enqueued " + rmRef);
}
}
es.shutdown();
System.out.println("All ClassLoaders successfully enqueued");
}
private static final String CLASSFILENAME = "ClassForName.class";
private static void setup() throws IOException {
String testclasses = System.getProperty("test.classes", ".");
// Create a temporary .jar file containing ClassForName.class
Path testClassesDir = Paths.get(testclasses);
JarUtils.createJarFile(jarFilePath, testClassesDir, CLASSFILENAME);
}
}
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