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 7122142
  27  * @summary Test deadlock situation when recursive annotations are parsed
  28  */
  29 
  30 import java.lang.annotation.Retention;
  31 import java.util.concurrent.CountDownLatch;
  32 import java.util.concurrent.atomic.AtomicInteger;
  33 
  34 import static java.lang.annotation.RetentionPolicy.RUNTIME;
  35 
  36 public class AnnotationTypeDeadlockTest {
  37 
  38     @Retention(RUNTIME)
  39     @AnnB
  40     public @interface AnnA {
  41     }
  42 
  43     @Retention(RUNTIME)
  44     @AnnA
  45     public @interface AnnB {
  46     }
  47 
  48     static class Task extends Thread {
  49         final CountDownLatch prepareLatch;
  50         final AtomicInteger goLatch;
  51         final Class<?> clazz;
  52 
  53         Task(CountDownLatch prepareLatch, AtomicInteger goLatch, Class<?> clazz) {
  54             super(clazz.getSimpleName());
  55             setDaemon(true); // in case it deadlocks
  56             this.prepareLatch = prepareLatch;
  57             this.goLatch = goLatch;
  58             this.clazz = clazz;
  59         }
  60 
  61         @Override
  62         public void run() {
  63             prepareLatch.countDown();  // notify we are prepared
  64             while (goLatch.get() > 0); // spin-wait before go
  65             clazz.getDeclaredAnnotations();
  66         }
  67     }
  68 
  69     static void dumpState(Task task) {
  70         System.err.println(
  71             "Task[" + task.getName() + "].state: " +
  72             task.getState() + " ..."
  73         );
  74         for (StackTraceElement ste : task.getStackTrace()) {
  75             System.err.println("\tat " + ste);
  76         }
  77         System.err.println();
  78     }
  79 
  80     public static void main(String[] args) throws Exception {
  81         CountDownLatch prepareLatch = new CountDownLatch(2);
  82         AtomicInteger goLatch = new AtomicInteger(1);
  83         Task taskA = new Task(prepareLatch, goLatch, AnnA.class);
  84         Task taskB = new Task(prepareLatch, goLatch, AnnB.class);
  85         taskA.start();
  86         taskB.start();
  87         // wait until both threads start-up
  88         prepareLatch.await();
  89         // let them go
  90         goLatch.set(0);
  91         // attempt to join them
  92         taskA.join(5000L);
  93         taskB.join(5000L);
  94 
  95         if (taskA.isAlive() || taskB.isAlive()) {
  96             dumpState(taskA);
  97             dumpState(taskB);
  98             throw new IllegalStateException(
  99                 taskA.getState() == Thread.State.BLOCKED &&
 100                 taskB.getState() == Thread.State.BLOCKED
 101                 ? "deadlock detected"
 102                 : "unexpected condition");
 103         }
 104     }
 105 }