test/jdk/java/lang/management/ManagementFactory/ThreadMXBeanProxy.java

*** 1,7 ****
  /*
!  * Copyright (c) 2005, 2016, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.
--- 1,7 ----
  /*
!  * Copyright (c) 2005, 2018, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.
*** 21,31 ****
   * questions.
   */
  
  /*
   * @test
!  * @bug     5086470 6358247 7193302
   * @summary Test type conversion when invoking ThreadMXBean.dumpAllThreads
   *          through proxy.
   * @author  Mandy Chung
   *
   * @run main ThreadMXBeanProxy
--- 21,31 ----
   * questions.
   */
  
  /*
   * @test
!  * @bug     5086470 6358247 7193302 8048215
   * @summary Test type conversion when invoking ThreadMXBean.dumpAllThreads
   *          through proxy.
   * @author  Mandy Chung
   *
   * @run main ThreadMXBeanProxy
*** 43,52 ****
--- 43,53 ----
      private static MBeanServer server =
          ManagementFactory.getPlatformMBeanServer();
      private static ThreadMXBean mbean;
      static Mutex mutex = new Mutex();
      static Object lock = new Object();
+     static Object waiter = new Object();
      static MyThread thread = new MyThread();
      public static void main(String[] argv) throws Exception {
          mbean = newPlatformMXBeanProxy(server,
                                         THREAD_MXBEAN_NAME,
                                         ThreadMXBean.class);
*** 66,75 ****
--- 67,82 ----
             } catch (InterruptedException e) {
                 throw new RuntimeException(e);
             }
          }
  
+         // 'thread' holds the mutex, which means it must also have the monitor of
+         // 'waiter' at least until it does the wait(). So we acquire the monitor of
+         // 'waiter' here, which ensures that 'thread' must be in wait()
+         synchronized(waiter) {
+         }
+ 
          long[] ids = new long[] { thread.getId() };
  
          // validate the local access
          ThreadInfo[] infos = getThreadMXBean().getThreadInfo(ids, true, true);
          if (infos.length != 1) {
*** 106,120 ****
          public MyThread() {
              super("MyThread");
          }
          public void run() {
              synchronized (lock) {
                  mutex.lock();
-                 Object o = new Object();
-                 synchronized(o) {
                      try {
!                         o.wait();
                      } catch (InterruptedException e) {
                          throw new RuntimeException(e);
                      }
                  }
              }
--- 113,126 ----
          public MyThread() {
              super("MyThread");
          }
          public void run() {
              synchronized (lock) {
+                 synchronized(waiter) {
                      mutex.lock();
                      try {
!                         waiter.wait();
                      } catch (InterruptedException e) {
                          throw new RuntimeException(e);
                      }
                  }
              }