1 /*
   2  * Copyright (c) 2006, 2011, 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 /*
  25  * @test
  26  * @bug 6399443
  27  * @summary Check for auto-shutdown and gc of singleThreadExecutors
  28  * @library /test/lib
  29  * @run main/othervm/timeout=1000 AutoShutdown
  30  * @author Martin Buchholz
  31  */
  32 
  33 import static java.util.concurrent.Executors.defaultThreadFactory;
  34 import static java.util.concurrent.Executors.newSingleThreadExecutor;
  35 
  36 import static java.util.concurrent.TimeUnit.MILLISECONDS;
  37 
  38 import java.lang.ref.WeakReference;
  39 import java.util.Arrays;
  40 import java.util.concurrent.ConcurrentLinkedQueue;
  41 import java.util.concurrent.CountDownLatch;
  42 import java.util.concurrent.Executor;
  43 import java.util.concurrent.TimeUnit;
  44 import jdk.test.lib.Utils;
  45 
  46 public class AutoShutdown {
  47     static final long LONG_DELAY_MS = Utils.adjustTimeout(10_000);
  48 
  49     static void await(CountDownLatch latch) throws InterruptedException {
  50         if (!latch.await(LONG_DELAY_MS, MILLISECONDS))
  51             throw new AssertionError("timed out waiting for latch");
  52     }
  53 
  54     private static void realMain(String[] args) throws Throwable {
  55         final Executor[] executors = {
  56             newSingleThreadExecutor(),
  57             newSingleThreadExecutor(defaultThreadFactory()),
  58             // TODO: should these executors also auto-shutdown?
  59             //newFixedThreadPool(1),
  60             //newSingleThreadScheduledExecutor(),
  61             //newSingleThreadScheduledExecutor(defaultThreadFactory()),
  62         };
  63         final ConcurrentLinkedQueue<WeakReference<Thread>> poolThreads
  64             = new ConcurrentLinkedQueue<>();
  65         final CountDownLatch threadStarted
  66             = new CountDownLatch(executors.length);
  67         final CountDownLatch pleaseProceed
  68             = new CountDownLatch(1);
  69         Runnable task = new Runnable() { public void run() {
  70             try {
  71                 poolThreads.add(new WeakReference<>(Thread.currentThread()));
  72                 threadStarted.countDown();
  73                 await(pleaseProceed);
  74             } catch (Throwable t) { unexpected(t); }
  75         }};
  76         for (Executor executor : executors)
  77             executor.execute(task);
  78         await(threadStarted);
  79         pleaseProceed.countDown();
  80         Arrays.fill(executors, null);   // make executors unreachable
  81         boolean done = false;
  82         for (long timeout = 1L; !done && timeout <= 128L; timeout *= 2) {
  83             System.gc();
  84             done = true;
  85             for (WeakReference<Thread> ref : poolThreads) {
  86                 Thread thread = ref.get();
  87                 if (thread != null) {
  88                     TimeUnit.SECONDS.timedJoin(thread, timeout);
  89                     if (thread.isAlive())
  90                         done = false;
  91                 }
  92             }
  93         }
  94         if (!done)
  95             throw new AssertionError("pool threads did not terminate");
  96     }
  97 
  98     //--------------------- Infrastructure ---------------------------
  99     static volatile int passed = 0, failed = 0;
 100     static void pass() {passed++;}
 101     static void fail() {failed++; Thread.dumpStack();}
 102     static void fail(String msg) {System.out.println(msg); fail();}
 103     static void unexpected(Throwable t) {failed++; t.printStackTrace();}
 104     static void equal(Object x, Object y) {
 105         if (x == null ? y == null : x.equals(y)) pass();
 106         else fail(x + " not equal to " + y);}
 107     public static void main(String[] args) throws Throwable {
 108         try {realMain(args);} catch (Throwable t) {unexpected(t);}
 109         System.out.printf("%nPassed = %d, failed = %d%n%n", passed, failed);
 110         if (failed > 0) throw new AssertionError("Some tests failed");}
 111 }