1 /*

     2  * Copyright (c) 2013, 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 7038914

    27  * @summary Verify that the reference handler does not die after an OOME allocating the InterruptedException object

    28  * @run main/othervm -Xmx16M -XX:-UseTLAB OOMEInReferenceHandler

    29  * @author peter.levart@gmail.com

    30  */

    31 

    32 import java.lang.ref.*;

    33 

    34 public class OOMEInReferenceHandler {

    35      static Object[] fillHeap() {

    36          Object[] first = null, last = null;

    37          int size = 1 << 20;

    38          while (size > 0) {

    39              try {

    40                  Object[] array = new Object[size];

    41                  if (first == null) {

    42                      first = array;

    43                  } else {

    44                      last[0] = array;

    45                  }

    46                  last = array;

    47              } catch (OutOfMemoryError oome) {

    48                  size = size >>> 1;

    49              }

    50          }

    51          return first;

    52      }

    53 

    54      public static void main(String[] args) throws Exception {

    55          // preinitialize the InterruptedException class so that the reference handler

    56          // does not die due to OOME when loading the class if it is the first use

    57          InterruptedException ie = new InterruptedException("dummy");

    58 

    59          ThreadGroup tg = Thread.currentThread().getThreadGroup();

    60          for (

    61              ThreadGroup tgn = tg;

    62              tgn != null;

    63              tg = tgn, tgn = tg.getParent()

    64              )

    65              ;

    66 

    67          Thread[] threads = new Thread[tg.activeCount()];

    68          Thread referenceHandlerThread = null;

    69          int n = tg.enumerate(threads);

    70          for (int i = 0; i < n; i++) {

    71              if ("Reference Handler".equals(threads[i].getName())) {

    72                  referenceHandlerThread = threads[i];

    73              }

    74          }

    75 

    76          if (referenceHandlerThread == null) {

    77              throw new IllegalStateException("Couldn't find Reference Handler thread.");

    78          }

    79 

    80          ReferenceQueue<Object> refQueue = new ReferenceQueue<>();

    81          Object referent = new Object();

    82          WeakReference<Object> weakRef = new WeakReference<>(referent, refQueue);

    83 

    84          Object waste = fillHeap();

    85 

    86          referenceHandlerThread.interrupt();

    87 

    88          // allow referenceHandlerThread some time to throw OOME

    89          Thread.sleep(500L);

    90 

    91          // release waste & referent

    92          waste = null;

    93          referent = null;

    94 

    95          // wait at most 10 seconds for success or failure

    96          for (int i = 0; i < 20; i++) {

    97              if (refQueue.poll() != null) {

    98                  // Reference Handler thread still working -> success

    99                  return;

   100              }

   101              System.gc();

   102              Thread.sleep(500L); // wait a little to allow GC to do it's work before allocating objects

   103              if (!referenceHandlerThread.isAlive()) {

   104                  // Reference Handler thread died -> failure

   105                  throw new Exception("Reference Handler thread died.");

   106              }

   107          }

   108 

   109          // no sure answer after 10 seconds

   110          throw new IllegalStateException("Reference Handler thread stuck.");

   111      }

   112 }