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 }