1 /*
   2  * Copyright (c) 2015, 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 import java.lang.management.*;
  25 import java.util.*;
  26 import java.util.concurrent.*;
  27 import java.util.concurrent.atomic.*;
  28 
  29 /*
  30  * @test
  31  * @bug     6588467
  32  * @summary Basic test of ThreadInfo.isDaemon
  33  * @author  Jeremy Manson
  34  */
  35 public class ThreadDaemonTest {
  36 
  37     public static void main(String[] args) throws Exception {
  38         final int NUM_THREADS = 20;
  39         final String THREAD_PREFIX = "ThreadDaemonTest-";
  40 
  41         final CountDownLatch started = new CountDownLatch(NUM_THREADS);
  42         final CountDownLatch finished = new CountDownLatch(1);
  43         final AtomicReference<Exception> fail = new AtomicReference<>(null);
  44 
  45         Thread[] allThreads = new Thread[NUM_THREADS];
  46         ThreadMXBean mbean = ManagementFactory.getThreadMXBean();
  47         Random rand = new Random();
  48 
  49         for (int i = 0; i < NUM_THREADS; i++) {
  50             allThreads[i] = new Thread(new Runnable() {
  51                     public void run() {
  52                         try {
  53                             started.countDown();
  54                             finished.await();
  55                         } catch (InterruptedException e) {
  56                             fail.set(new Exception(
  57                                 "Unexpected InterruptedException"));
  58                         }
  59                     }
  60                 }, THREAD_PREFIX + i);
  61             allThreads[i].setDaemon(rand.nextBoolean());
  62             allThreads[i].start();
  63         }
  64 
  65         started.await();
  66         try {
  67             ThreadInfo[] allThreadInfos = mbean.dumpAllThreads(false, false);
  68             int count = 0;
  69             for (int i = 0; i < allThreadInfos.length; i++) {
  70                 String threadName = allThreadInfos[i].getThreadName();
  71                 if (threadName.startsWith(THREAD_PREFIX)) {
  72                     count++;
  73                     String[] nameAndNumber = threadName.split("-");
  74                     int threadNum = Integer.parseInt(nameAndNumber[1]);
  75                     if (allThreads[threadNum].isDaemon() !=
  76                         allThreadInfos[i].isDaemon()) {
  77                         throw new RuntimeException(
  78                             allThreads[threadNum] + " is not like " +
  79                             allThreadInfos[i] + ". TEST FAILED.");
  80                     }
  81                 }
  82             }
  83             if (count != NUM_THREADS) {
  84                 throw new RuntimeException("Wrong number of threads examined");
  85             }
  86         }
  87         finally { finished.countDown(); }
  88 
  89         for (int i = 0; i < NUM_THREADS; i++) {
  90             allThreads[i].join();
  91         }
  92         if (fail.get() != null) {
  93             throw fail.get();
  94         }
  95     }
  96 }