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 }