1 /*
2 * Copyright (c) 2007, 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 6571733 6460501
27 * @summary Check that regaining a read lock succeeds after a write
28 * lock attempt times out
29 */
30 import java.util.concurrent.locks.*;
31 import java.util.concurrent.*;
32
33 public class Bug6571733 {
34
35 void test(String[] args) throws Throwable {
36 test(true);
37 test(false);
38 }
39
40 void test(boolean fairness) throws Throwable {
41 final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(fairness);
42
43 // obtain read lock
44 lock.readLock().lock();
45
46 Thread thread = new Thread() { public void run() {
47 try {
48 check(! lock.writeLock().tryLock(0, TimeUnit.DAYS));
49
50 lock.readLock().lock();
51 lock.readLock().unlock();
52 } catch (Throwable t) { unexpected(t); }}};
53
54 thread.start();
55 thread.join();
56 }
57
58 //--------------------- Infrastructure ---------------------------
59 volatile int passed = 0, failed = 0;
60 void pass() {passed++;}
61 void fail() {failed++; Thread.dumpStack();}
62 void fail(String msg) {System.err.println(msg); fail();}
63 void unexpected(Throwable t) {failed++; t.printStackTrace();}
64 void check(boolean cond) {if (cond) pass(); else fail();}
65 public static void main(String[] args) throws Throwable {
66 new Bug6571733().instanceMain(args);}
67 void instanceMain(String[] args) throws Throwable {
68 try {test(args);} catch (Throwable t) {unexpected(t);}
69 System.out.printf("%nPassed = %d, failed = %d%n%n", passed, failed);
70 if (failed > 0) throw new AssertionError("Some tests failed");}
71 }
--- EOF ---