1 /*
   2  * Copyright (c) 1999, 2016, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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   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
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  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
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  23 
  24 /**
  25  * @test
  26  * @bug 4176355
  27  * @summary Stopping a ThreadGroup that contains the current thread has
  28  *          unpredictable results.
  29  */
  30 
  31 import java.util.concurrent.CountDownLatch;
  32 
  33 public class Stop {
  34 
  35     private static final CountDownLatch ready = new CountDownLatch(1);
  36     private static final ThreadGroup group = new ThreadGroup("");
  37 
  38     private static final Thread second = new Thread(group, () -> {
  39         ready.countDown();
  40         while (true) { // keep it alive 
  41         }
  42     });
  43 
  44     private static final Thread first = new Thread(group, () -> {
  45         // Wait until "second" is started
  46         try {
  47             ready.await();
  48         } catch (InterruptedException shouldNotHappen) {}
  49         // Now stop the group
  50         group.stop();
  51     });
  52 
  53     public static void main(String[] args) throws Exception {
  54         // Launch two threads as part of the same thread group
  55         first.start();
  56         second.start();
  57 
  58         // Check that the second thread is terminated when the
  59         // first thread terminates the thread group.
  60         second.join();
  61         // Test passed - if never get here the test times out and fails.
  62     }
  63 }