From 39e40cb84f9cd8cb2a816546633bb36e033ea3da Mon Sep 17 00:00:00 2001 From: bae Date: Wed, 4 Feb 2009 14:06:18 +0300 Subject: [PATCH] 6799583: LogManager shutdown hook may cause a memory leak. Reviewed-by: igor, swamyv --- .../classes/java/util/logging/LogManager.java | 8 + .../util/logging/ClassLoaderLeakTest.java | 190 ++++++++++++++++++ 2 files changed, 198 insertions(+) create mode 100644 test/java/util/logging/ClassLoaderLeakTest.java diff --git a/src/share/classes/java/util/logging/LogManager.java b/src/share/classes/java/util/logging/LogManager.java index 412f74940..fc8f080eb 100644 --- a/src/share/classes/java/util/logging/LogManager.java +++ b/src/share/classes/java/util/logging/LogManager.java @@ -215,6 +215,14 @@ public class LogManager { // This private class is used as a shutdown hook. // It does a "reset" to close all open handlers. private class Cleaner extends Thread { + + private Cleaner() { + /* Set context class loader to null in order to avoid + * keeping a strong reference to an application classloader. + */ + this.setContextClassLoader(null); + } + public void run() { // This is to ensure the LogManager. is completed // before synchronized block. Otherwise deadlocks are possible. diff --git a/test/java/util/logging/ClassLoaderLeakTest.java b/test/java/util/logging/ClassLoaderLeakTest.java new file mode 100644 index 000000000..988041472 --- /dev/null +++ b/test/java/util/logging/ClassLoaderLeakTest.java @@ -0,0 +1,190 @@ +/* + * Copyright 2009 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, + * CA 95054 USA or visit www.sun.com if you need additional information or + * have any questions. + */ + +/** + * @test + * @bug 6799583 + * + * @summary Test verifes that LogManager shutdown hook does not cause + * an application classloader leaks. + * + * @run main/othervm ClassLoaderLeakTest + */ + +import java.io.File; +import java.lang.ref.WeakReference; +import java.lang.reflect.Constructor; +import java.lang.reflect.Method; +import java.net.MalformedURLException; +import java.net.URL; +import java.net.URLClassLoader; +import java.util.concurrent.CountDownLatch; +import java.util.logging.Logger; +import java.util.logging.Logger; + +public class ClassLoaderLeakTest { + + private static CountDownLatch doneSignal; + private static CountDownLatch launchSignal; + private static ThreadGroup appsThreadGroup; + private static Throwable launchFailure = null; + + public static void main(String[] args) { + appsThreadGroup = new ThreadGroup("MyAppsThreadGroup"); + doneSignal = new CountDownLatch(1); + launchSignal = new CountDownLatch(1); + + Runnable launcher = new Runnable() { + public void run() { + try { + ClassLoader cl = + Thread.currentThread().getContextClassLoader(); + Class appMain = cl.loadClass("AppTest"); + Method launch = + appMain.getDeclaredMethod("launch", doneSignal.getClass()); + + Constructor c = appMain.getConstructor(); + + Object o = c.newInstance(); + + launch.invoke(o, doneSignal); + + } catch (Throwable e) { + launchFailure = e; + } finally { + launchSignal.countDown(); + } + } + }; + + /* prepare test class loader */ + URL pwd = null; + try { + + pwd = new File(System.getProperty("test.classes",".")).toURL(); + } catch (MalformedURLException e) { + throw new RuntimeException("Test failed.", e); + } + URL[] urls = new URL[] { pwd }; + + MyClassLoader appClassLoader = new MyClassLoader(urls, "test0"); + WeakReference ref = + new WeakReference(appClassLoader); + + + Thread appThread = new Thread(appsThreadGroup, launcher, "AppThread-0"); + appThread.setContextClassLoader(appClassLoader); + + appThread.start(); + appClassLoader = null; + launcher = null; + appThread = null; + + /* wait for laucnh completion */ + try { + launchSignal.await(); + } catch (InterruptedException e) { + } + + /* check if launch failed */ + if (launchFailure != null) { + throw new RuntimeException("Test failed.", launchFailure); + } + + /* wait for test app excution completion */ + try { + doneSignal.await(); + } catch (InterruptedException e) { + } + + /* give a chence to GC */ + waitAndGC(5); + + if (ref.get() != null) { + throw new RuntimeException("Test failed: classloader is still alive"); + } + + System.out.println("Test passed."); + } + + private static class MyClassLoader extends URLClassLoader { + + private static boolean verbose = + Boolean.getBoolean("verboseClassLoading"); + private String uniqClassName; + + public MyClassLoader(URL[] urls, String uniq) { + super(urls); + + uniqClassName = uniq; + } + + public Class loadClass(String name) throws ClassNotFoundException { + if (verbose) { + System.out.printf("%s: load class %s\n", uniqClassName, name); + } + if (uniqClassName.equals(name)) { + return Object.class; + } + return super.loadClass(name); + } + + public String toString() { + return "MyClassLoader(" + uniqClassName + ")"; + } + } + + private static void waitAndGC(int sec) { + int cnt = sec; + System.out.print("Wait "); + while (cnt-- > 0) { + try { + Thread.sleep(1000); + } catch (InterruptedException e) { + } + // do GC every 3 seconds + if (cnt % 3 == 2) { + System.gc(); + System.out.print("+"); + } else { + System.out.print("."); + } + //checkErrors(); + } + System.out.println(""); + } +} + + +class AppTest { + public AppTest() { + + } + + public void launch(CountDownLatch done) { + Logger log = Logger.getLogger("app_test_logger"); + log.fine("Test app is launched"); + + done.countDown(); + } +} -- GitLab