1 /*
   2  * Copyright (c) 2009, 2012, 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     6799583
  27  *
  28  * @summary Test verifes that LogManager shutdown hook does not cause
  29  *          an application classloader leaks.
  30  *
  31  * @run     main/othervm ClassLoaderLeakTest
  32  */
  33 
  34 import java.io.File;
  35 import java.lang.ref.WeakReference;
  36 import java.lang.reflect.Constructor;
  37 import java.lang.reflect.Method;
  38 import java.net.MalformedURLException;
  39 import java.net.URL;
  40 import java.net.URLClassLoader;
  41 import java.util.concurrent.CountDownLatch;
  42 import java.util.logging.Logger;
  43 
  44 public class ClassLoaderLeakTest {
  45 
  46     private static CountDownLatch doneSignal;
  47     private static CountDownLatch launchSignal;
  48     private static ThreadGroup appsThreadGroup;
  49     private static Throwable launchFailure = null;
  50 
  51     public static void main(String[] args) {
  52         appsThreadGroup = new ThreadGroup("MyAppsThreadGroup");
  53         doneSignal = new CountDownLatch(1);
  54         launchSignal = new CountDownLatch(1);
  55 
  56         Runnable launcher = new Runnable() {
  57             public void run() {
  58                 try {
  59                     ClassLoader cl =
  60                         Thread.currentThread().getContextClassLoader();
  61                     Class<?> appMain = cl.loadClass("AppTest");
  62                     Method launch =
  63                         appMain.getDeclaredMethod("launch", doneSignal.getClass());
  64 
  65                     Constructor<?> c = appMain.getConstructor();
  66 
  67                     Object o = c.newInstance();
  68 
  69                     launch.invoke(o, doneSignal);
  70 
  71                 } catch (Throwable e) {
  72                     launchFailure = e;
  73                 } finally {
  74                     launchSignal.countDown();
  75                 }
  76             }
  77         };
  78 
  79         /* prepare test  class loader */
  80         URL pwd = null;
  81         try {
  82             pwd = new File(System.getProperty("test.classes",".")).toURI().toURL();
  83         } catch (MalformedURLException e) {
  84             throw new RuntimeException("Test failed.", e);
  85         }
  86         URL[] urls = new URL[] { pwd };
  87 
  88          MyClassLoader appClassLoader = new MyClassLoader(urls, "test0");
  89          WeakReference<MyClassLoader> ref =
  90                  new WeakReference<>(appClassLoader);
  91 
  92 
  93          Thread appThread = new Thread(appsThreadGroup, launcher, "AppThread-0");
  94          appThread.setContextClassLoader(appClassLoader);
  95 
  96          appThread.start();
  97          appClassLoader = null;
  98          launcher = null;
  99          appThread = null;
 100 
 101          /* wait for laucnh completion */
 102          try {
 103              launchSignal.await();
 104          } catch (InterruptedException e) {
 105          }
 106 
 107          /* check if launch failed */
 108          if (launchFailure != null) {
 109              throw new RuntimeException("Test failed.", launchFailure);
 110          }
 111 
 112          /* wait for test app excution completion */
 113          try {
 114              doneSignal.await();
 115          } catch (InterruptedException e) {
 116          }
 117 
 118          /* give a chence to GC */
 119          waitAndGC(5);
 120 
 121          if (ref.get() != null) {
 122              throw new RuntimeException("Test failed: classloader is still alive");
 123          }
 124 
 125          System.out.println("Test passed.");
 126     }
 127 
 128     private static class MyClassLoader extends URLClassLoader {
 129 
 130         private static boolean verbose =
 131             Boolean.getBoolean("verboseClassLoading");
 132         private String uniqClassName;
 133 
 134         public MyClassLoader(URL[] urls, String uniq) {
 135             super(urls);
 136 
 137             uniqClassName = uniq;
 138         }
 139 
 140         public Class<?> loadClass(String name) throws ClassNotFoundException {
 141             if (verbose) {
 142                 System.out.printf("%s: load class %s\n", uniqClassName, name);
 143             }
 144             if (uniqClassName.equals(name)) {
 145                 return Object.class;
 146             }
 147             return super.loadClass(name);
 148         }
 149 
 150         public String toString() {
 151             return "MyClassLoader(" + uniqClassName + ")";
 152         }
 153     }
 154 
 155     private static void waitAndGC(int sec) {
 156         int cnt = sec;
 157         System.out.print("Wait ");
 158         while (cnt-- > 0) {
 159             try {
 160                 Thread.sleep(1000);
 161             } catch (InterruptedException e) {
 162             }
 163             // do GC every 3 seconds
 164             if (cnt % 3 == 2) {
 165                 System.gc();
 166                 System.out.print("+");
 167             } else {
 168                 System.out.print(".");
 169             }
 170             //checkErrors();
 171         }
 172         System.out.println("");
 173     }
 174 }
 175 
 176 
 177 class AppTest {
 178     public AppTest() {
 179 
 180     }
 181 
 182     public void launch(CountDownLatch done) {
 183         Logger log = Logger.getLogger("app_test_logger");
 184         log.fine("Test app is launched");
 185 
 186         done.countDown();
 187     }
 188 }