test/java/util/concurrent/ConcurrentQueues/OfferRemoveLoops.java

*** 1,7 ****
  /*
!  * Copyright (c) 2005, 2010, 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, 2014, 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.
*** 74,83 ****
--- 74,85 ----
  
          /** Poor man's bounded buffer. */
          final AtomicLong approximateCount = new AtomicLong(0L);
  
          abstract class CheckedThread extends Thread {
+             protected volatile boolean stopRequest = false;
+ 
              CheckedThread(String name) {
                  super(name);
                  setDaemon(true);
                  start();
              }
*** 85,157 ****
              protected boolean quittingTime() {
                  return System.nanoTime() - quittingTimeNanos > 0;
              }
              /** Polls occasionally for quitting time. */
              protected boolean quittingTime(long i) {
!                 return (i % 1024) == 0 && quittingTime();
              }
              abstract protected void realRun();
              public void run() {
                  try { realRun(); } catch (Throwable t) { unexpected(t); }
              }
          }
  
!         Thread offerer = new CheckedThread("offerer") {
              protected void realRun() {
                  final long chunkSize = getRandom().nextInt(maxChunkSize) + 2;
                  long c = 0;
                  for (long i = 0; ! quittingTime(i); i++) {
                      if (q.offer(Long.valueOf(c))) {
                          if ((++c % chunkSize) == 0) {
                              approximateCount.getAndAdd(chunkSize);
                              while (approximateCount.get() > maxQueueSize)
!                                 Thread.yield();
                          }
                      } else {
!                         Thread.yield();
                      }}}};
  
!         Thread remover = new CheckedThread("remover") {
              protected void realRun() {
                  final long chunkSize = getRandom().nextInt(maxChunkSize) + 2;
                  long c = 0;
                  for (long i = 0; ! quittingTime(i); i++) {
                      if (q.remove(Long.valueOf(c))) {
                          if ((++c % chunkSize) == 0) {
                              approximateCount.getAndAdd(-chunkSize);
                          }
                      } else {
!                         Thread.yield();
                      }
                  }
                  q.clear();
                  approximateCount.set(0); // Releases waiting offerer thread
              }};
  
!         Thread scanner = new CheckedThread("scanner") {
              protected void realRun() {
                  final Random rnd = getRandom();
                  while (! quittingTime()) {
                      switch (rnd.nextInt(3)) {
                      case 0: checkNotContainsNull(q); break;
                      case 1: q.size(); break;
                      case 2: checkNotContainsNull
                              (Arrays.asList(q.toArray(new Long[0])));
                          break;
                      }
!                     Thread.yield();
                  }}};
  
!         for (Thread thread : new Thread[] { offerer, remover, scanner }) {
              thread.join(timeoutMillis + testDurationMillis);
              if (thread.isAlive()) {
                  System.err.printf("Hung thread: %s%n", thread.getName());
                  failed++;
                  for (StackTraceElement e : thread.getStackTrace())
                      System.err.println(e);
                  // Kludge alert
!                 thread.stop();
                  thread.join(timeoutMillis);
              }
          }
      }
  
--- 87,167 ----
              protected boolean quittingTime() {
                  return System.nanoTime() - quittingTimeNanos > 0;
              }
              /** Polls occasionally for quitting time. */
              protected boolean quittingTime(long i) {
!                 return stopRequest || quittingTime() && (i % 1024 == 0 || i < 1024);
!             }
!             protected void giveupCPU(){
!                 try {
!                     Thread.sleep(0L);
!                 } catch (InterruptedException ignore) {}
              }
              abstract protected void realRun();
              public void run() {
                  try { realRun(); } catch (Throwable t) { unexpected(t); }
              }
+             public void stopThread() {
+                 stopRequest = true;
+             }
          }
  
!         CheckedThread offerer = new CheckedThread("offerer") {
              protected void realRun() {
                  final long chunkSize = getRandom().nextInt(maxChunkSize) + 2;
                  long c = 0;
                  for (long i = 0; ! quittingTime(i); i++) {
                      if (q.offer(Long.valueOf(c))) {
                          if ((++c % chunkSize) == 0) {
                              approximateCount.getAndAdd(chunkSize);
                              while (approximateCount.get() > maxQueueSize)
!                                 giveupCPU();
                          }
                      } else {
!                         giveupCPU();
                      }}}};
  
!         CheckedThread remover = new CheckedThread("remover") {
              protected void realRun() {
                  final long chunkSize = getRandom().nextInt(maxChunkSize) + 2;
                  long c = 0;
                  for (long i = 0; ! quittingTime(i); i++) {
                      if (q.remove(Long.valueOf(c))) {
                          if ((++c % chunkSize) == 0) {
                              approximateCount.getAndAdd(-chunkSize);
                          }
                      } else {
!                         giveupCPU();
                      }
                  }
                  q.clear();
                  approximateCount.set(0); // Releases waiting offerer thread
              }};
  
!         CheckedThread scanner = new CheckedThread("scanner") {
              protected void realRun() {
                  final Random rnd = getRandom();
                  while (! quittingTime()) {
                      switch (rnd.nextInt(3)) {
                      case 0: checkNotContainsNull(q); break;
                      case 1: q.size(); break;
                      case 2: checkNotContainsNull
                              (Arrays.asList(q.toArray(new Long[0])));
                          break;
                      }
!                     giveupCPU();
                  }}};
  
!         for (CheckedThread thread : new CheckedThread[] { offerer, remover, scanner }) {
              thread.join(timeoutMillis + testDurationMillis);
              if (thread.isAlive()) {
                  System.err.printf("Hung thread: %s%n", thread.getName());
                  failed++;
                  for (StackTraceElement e : thread.getStackTrace())
                      System.err.println(e);
                  // Kludge alert
!                 thread.stopThread();
                  thread.join(timeoutMillis);
              }
          }
      }