1 /*
   2  * Copyright (c) 2013, 2015, 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 7122142
  27  * @summary Test deadlock situation when recursive annotations are parsed
  28  * @modules java.management
  29  */
  30 
  31 import java.lang.annotation.Retention;
  32 import java.lang.management.ManagementFactory;
  33 import java.lang.management.ThreadInfo;
  34 import java.lang.management.ThreadMXBean;
  35 import java.util.concurrent.CountDownLatch;
  36 import java.util.concurrent.atomic.AtomicInteger;
  37 
  38 import static java.lang.annotation.RetentionPolicy.RUNTIME;
  39 
  40 public class AnnotationTypeDeadlockTest {
  41 
  42     @Retention(RUNTIME)
  43     @AnnB
  44     public @interface AnnA {
  45     }
  46 
  47     @Retention(RUNTIME)
  48     @AnnA
  49     public @interface AnnB {
  50     }
  51 
  52     static class Task extends Thread {
  53         final CountDownLatch prepareLatch;
  54         final AtomicInteger goLatch;
  55         final Class<?> clazz;
  56 
  57         Task(CountDownLatch prepareLatch, AtomicInteger goLatch, Class<?> clazz) {
  58             super(clazz.getSimpleName());
  59             setDaemon(true); // in case it deadlocks
  60             this.prepareLatch = prepareLatch;
  61             this.goLatch = goLatch;
  62             this.clazz = clazz;
  63         }
  64 
  65         @Override
  66         public void run() {
  67             prepareLatch.countDown();  // notify we are prepared
  68             while (goLatch.get() > 0); // spin-wait before go
  69             clazz.getDeclaredAnnotations();
  70         }
  71     }
  72 
  73     public static void main(String[] args) throws Exception {
  74         CountDownLatch prepareLatch = new CountDownLatch(2);
  75         AtomicInteger goLatch = new AtomicInteger(1);
  76         Task taskA = new Task(prepareLatch, goLatch, AnnA.class);
  77         Task taskB = new Task(prepareLatch, goLatch, AnnB.class);
  78         taskA.start();
  79         taskB.start();
  80         // wait until both threads start-up
  81         prepareLatch.await();
  82         // let them go
  83         goLatch.set(0);
  84         // obtain ThreadMXBean
  85         ThreadMXBean threadBean = ManagementFactory.getThreadMXBean();
  86         // wait for threads to finish or dead-lock
  87         while (taskA.isAlive() || taskB.isAlive()) {
  88             // attempt to join threads
  89             taskA.join(500L);
  90             taskB.join(500L);
  91             // detect dead-lock
  92             long[] deadlockedIds = threadBean.findMonitorDeadlockedThreads();
  93             if (deadlockedIds != null && deadlockedIds.length > 0) {
  94                 StringBuilder sb = new StringBuilder("deadlock detected:\n\n");
  95                 for (ThreadInfo ti : threadBean.getThreadInfo(deadlockedIds, Integer.MAX_VALUE)) {
  96                     sb.append(ti);
  97                 }
  98                 throw new IllegalStateException(sb.toString());
  99             }
 100         }
 101     }
 102 }