code: // from gee.cs.oswego.edu/home/jsr166/jsr166
  
  package jsr166tests.jtreg.util.concurrent.ThreadPoolExecutor;
  
  /*
   * Copyright 2007 Sun Microsystems, Inc.  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.
   *
   * This code is distributed in the hope that it will be useful, but WITHOUT
   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   * version 2 for more details (a copy is included in the LICENSE file that
   * accompanied this code).
   *
   * You should have received a copy of the GNU General Public License version
   * 2 along with this work; if not, write to the Free Software Foundation,
   * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
   * CA 95054 USA or visit www.sun.com if you need additional information or
   * have any questions.
   */
  
  /*
   * @test
   * @bug 6523756
   * @summary Race task submission against shutdownNow
   * @author Martin Buchholz
   */
  
  // For extra chances to detect shutdownNow vs. execute races,
  // crank up the iterations to, say 1<<22 and
  // add a call to Thread.yield() before the call to t.start()
  // in ThreadPoolExecutor.addWorker.
  
  import java.util.*;
  import java.util.concurrent.*;
  
  public class ShutdownNowExecuteRace {
      static volatile boolean quit = false;
      static volatile ThreadPoolExecutor pool = null;
  
      final static Runnable sleeper = new Runnable() { public void run() {
          final long ONE_HOUR = 1000L * 60L * 60L;
          try { Thread.sleep(ONE_HOUR); }
          catch (InterruptedException ie) {}
          catch (Throwable t) { unexpected(t); }}};
  
      static void realMain(String[] args) throws Throwable {
          final int iterations = 1 << 8;
          Thread thread = new Thread() { public void run() {
              while (! quit) {
                  ThreadPoolExecutor pool = ShutdownNowExecuteRace.pool;
                  if (pool != null)
                      try { pool.execute(sleeper); }
                      catch (RejectedExecutionException e) {/* OK */}
                      catch (Throwable t) { unexpected(t); }}}};
          thread.start();
          for (int i = 0; i < iterations; i++) {
              pool = new ThreadPoolExecutor(
                  10, 10, 3L, TimeUnit.DAYS,
                  new ArrayBlockingQueue<Runnable>(10));
              pool.shutdownNow();
              check(pool.awaitTermination(3L, TimeUnit.MINUTES));
          }
          quit = true;
          thread.join();
      }
  
      //--------------------- Infrastructure ---------------------------
      static volatile int passed = 0, failed = 0;
      static void pass() {passed++;}
      static void fail() {failed++; Thread.dumpStack();}
      static void fail(String msg) {System.out.println(msg); fail();}
      static void unexpected(Throwable t) {failed++; t.printStackTrace();}
      static void check(boolean cond) {if (cond) pass(); else fail();}
      static void equal(Object x, Object y) {
          if (x == null ? y == null : x.equals(y)) pass();
          else fail(x + " not equal to " + y);}
      public static void main(String[] args) throws Throwable {
          try {realMain(args);} catch (Throwable t) {unexpected(t);}
          System.out.printf("%nPassed = %d, failed = %d%n%n", passed, failed);
          if (failed > 0) throw new AssertionError("Some tests failed");}
      private static abstract class Fun {abstract void f() throws Throwable;}
      static void THROWS(Class<? extends Throwable> k, Fun... fs) {
          for (Fun f : fs)
              try { f.f(); fail("Expected " + k.getName() + " not thrown"); }
              catch (Throwable t) {
                  if (k.isAssignableFrom(t.getClass())) pass();
                  else unexpected(t);}}
      private static abstract class CheckedThread extends Thread {
          abstract void realRun() throws Throwable;
          public void run() {
              try {realRun();} catch (Throwable t) {unexpected(t);}}}
  }
  