1 /*
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   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
  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
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  23 
  24 /**
  25  * @test
  26  * @bug 8167108
  27  * @summary Stress test java.lang.Thread.setPriority() at thread exit.
  28  * @run main/othervm -Xlog:thread+smr=debug SetPriorityAtExit
  29  */
  30 
  31 import java.util.concurrent.CountDownLatch;
  32 
  33 public class SetPriorityAtExit extends Thread {
  34     final static int N_THREADS = 32;
  35     final static int N_LATE_CALLS = 2000;
  36 
  37     final static int MIN = java.lang.Thread.MIN_PRIORITY;
  38     final static int NORM = java.lang.Thread.NORM_PRIORITY;
  39 
  40     public CountDownLatch exitSyncObj = new CountDownLatch(1);
  41     public CountDownLatch startSyncObj = new CountDownLatch(1);
  42 
  43     @Override
  44     public void run() {
  45         // Tell main thread we have started.
  46         startSyncObj.countDown();
  47         try {
  48             // Wait for main thread to interrupt us so we
  49             // can race to exit.
  50             exitSyncObj.await();
  51         } catch (InterruptedException e) {
  52             // ignore because we expect one
  53         }
  54     }
  55 
  56     public static void main(String[] args) {
  57         SetPriorityAtExit threads[] = new SetPriorityAtExit[N_THREADS];
  58 
  59         int prio = MIN;
  60         for (int i = 0; i < N_THREADS; i++ ) {
  61             threads[i] = new SetPriorityAtExit();
  62             int late_count = 1;
  63             threads[i].start();
  64             try {
  65                 // Wait for the worker thread to get going.
  66                 threads[i].startSyncObj.await();
  67 
  68                 // This interrupt() call will break the worker out of
  69                 // the exitSyncObj.await() call and the setPriority()
  70                 // calls will come in during thread exit.
  71                 threads[i].interrupt();
  72                 for (; late_count <= N_LATE_CALLS; late_count++) {
  73                     threads[i].setPriority(prio);
  74                     if (prio == MIN) {
  75                         prio = NORM;
  76                     } else {
  77                         prio = MIN;
  78                     }
  79 
  80                     if (!threads[i].isAlive()) {
  81                         // Done with Thread.setPriority() calls since
  82                         // thread is not alive.
  83                         break;
  84                     }
  85                 }
  86             } catch (InterruptedException e) {
  87                 throw new Error("Unexpected: " + e);
  88             }
  89 
  90             System.out.println("INFO: thread #" + i + ": made " + late_count +
  91                                " late calls to java.lang.Thread.setPriority()");
  92             System.out.println("INFO: thread #" + i + ": N_LATE_CALLS==" +
  93                                N_LATE_CALLS + " value is " +
  94                                ((late_count >= N_LATE_CALLS) ? "NOT " : "") +
  95                                "large enough to cause a Thread.setPriority() " +
  96                                "call after thread exit.");
  97 
  98             try {
  99                 threads[i].join();
 100             } catch (InterruptedException e) {
 101                 throw new Error("Unexpected: " + e);
 102             }
 103             threads[i].setPriority(prio);
 104             if (threads[i].isAlive()) {
 105                 throw new Error("Expected !Thread.isAlive() after thread #" +
 106                                 i + " has been join()'ed");
 107             }
 108         }
 109 
 110         String cmd = System.getProperty("sun.java.command");
 111         if (cmd != null && !cmd.startsWith("com.sun.javatest.regtest.agent.MainWrapper")) {
 112             // Exit with success in a non-JavaTest environment:
 113             System.exit(0);
 114         }
 115     }
 116 }