/* * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ /* * This file is available under and governed by the GNU General Public * License version 2 only, as published by the Free Software Foundation. * However, the following notice accompanied the original version of this * file: * * Written by Doug Lea with assistance from members of JCP JSR-166 * Expert Group and released to the public domain, as explained at * http://creativecommons.org/publicdomain/zero/1.0/ * Other contributors include Andrew Wright, Jeffrey Hayes, * Pat Fisher, Mike Judd. */ import static java.util.concurrent.TimeUnit.MILLISECONDS; import java.util.Arrays; import java.util.Collection; import java.util.HashSet; import java.util.concurrent.CountDownLatch; import java.util.concurrent.atomic.AtomicBoolean; import java.util.concurrent.locks.Condition; import java.util.concurrent.locks.Lock; import java.util.concurrent.locks.ReentrantReadWriteLock; import junit.framework.AssertionFailedError; import junit.framework.Test; import junit.framework.TestSuite; public class ReentrantReadWriteLockTest extends JSR166TestCase { public static void main(String[] args) { main(suite(), args); } public static Test suite() { return new TestSuite(ReentrantReadWriteLockTest.class); } /** * A runnable calling lockInterruptibly */ class InterruptibleLockRunnable extends CheckedRunnable { final ReentrantReadWriteLock lock; InterruptibleLockRunnable(ReentrantReadWriteLock l) { lock = l; } public void realRun() throws InterruptedException { lock.writeLock().lockInterruptibly(); } } /** * A runnable calling lockInterruptibly that expects to be * interrupted */ class InterruptedLockRunnable extends CheckedInterruptedRunnable { final ReentrantReadWriteLock lock; InterruptedLockRunnable(ReentrantReadWriteLock l) { lock = l; } public void realRun() throws InterruptedException { lock.writeLock().lockInterruptibly(); } } /** * Subclass to expose protected methods */ static class PublicReentrantReadWriteLock extends ReentrantReadWriteLock { PublicReentrantReadWriteLock() { super(); } PublicReentrantReadWriteLock(boolean fair) { super(fair); } public Thread getOwner() { return super.getOwner(); } public Collection<Thread> getQueuedThreads() { return super.getQueuedThreads(); } public Collection<Thread> getWaitingThreads(Condition c) { return super.getWaitingThreads(c); } } /** * Releases write lock, checking that it had a hold count of 1. */ void releaseWriteLock(PublicReentrantReadWriteLock lock) { ReentrantReadWriteLock.WriteLock writeLock = lock.writeLock(); assertWriteLockedByMoi(lock); assertEquals(1, lock.getWriteHoldCount()); writeLock.unlock(); assertNotWriteLocked(lock); } /** * Spin-waits until lock.hasQueuedThread(t) becomes true. */ void waitForQueuedThread(PublicReentrantReadWriteLock lock, Thread t) { long startTime = System.nanoTime(); while (!lock.hasQueuedThread(t)) { if (millisElapsedSince(startTime) > LONG_DELAY_MS) throw new AssertionFailedError("timed out"); Thread.yield(); } assertTrue(t.isAlive()); assertNotSame(t, lock.getOwner()); } /** * Checks that lock is not write-locked. */ void assertNotWriteLocked(PublicReentrantReadWriteLock lock) { assertFalse(lock.isWriteLocked()); assertFalse(lock.isWriteLockedByCurrentThread()); assertFalse(lock.writeLock().isHeldByCurrentThread()); assertEquals(0, lock.getWriteHoldCount()); assertEquals(0, lock.writeLock().getHoldCount()); assertNull(lock.getOwner()); } /** * Checks that lock is write-locked by the given thread. */ void assertWriteLockedBy(PublicReentrantReadWriteLock lock, Thread t) { assertTrue(lock.isWriteLocked()); assertSame(t, lock.getOwner()); assertEquals(t == Thread.currentThread(), lock.isWriteLockedByCurrentThread()); assertEquals(t == Thread.currentThread(), lock.writeLock().isHeldByCurrentThread()); assertEquals(t == Thread.currentThread(), lock.getWriteHoldCount() > 0); assertEquals(t == Thread.currentThread(), lock.writeLock().getHoldCount() > 0); assertEquals(0, lock.getReadLockCount()); } /** * Checks that lock is write-locked by the current thread. */ void assertWriteLockedByMoi(PublicReentrantReadWriteLock lock) { assertWriteLockedBy(lock, Thread.currentThread()); } /** * Checks that condition c has no waiters. */ void assertHasNoWaiters(PublicReentrantReadWriteLock lock, Condition c) { assertHasWaiters(lock, c, new Thread[] {}); } /** * Checks that condition c has exactly the given waiter threads. */ void assertHasWaiters(PublicReentrantReadWriteLock lock, Condition c, Thread... threads) { lock.writeLock().lock(); assertEquals(threads.length > 0, lock.hasWaiters(c)); assertEquals(threads.length, lock.getWaitQueueLength(c)); assertEquals(threads.length == 0, lock.getWaitingThreads(c).isEmpty()); assertEquals(threads.length, lock.getWaitingThreads(c).size()); assertEquals(new HashSet<Thread>(lock.getWaitingThreads(c)), new HashSet<Thread>(Arrays.asList(threads))); lock.writeLock().unlock(); } enum AwaitMethod { await, awaitTimed, awaitNanos, awaitUntil } /** * Awaits condition "indefinitely" using the specified AwaitMethod. */ void await(Condition c, AwaitMethod awaitMethod) throws InterruptedException { long timeoutMillis = 2 * LONG_DELAY_MS; switch (awaitMethod) { case await: c.await(); break; case awaitTimed: assertTrue(c.await(timeoutMillis, MILLISECONDS)); break; case awaitNanos: long timeoutNanos = MILLISECONDS.toNanos(timeoutMillis); long nanosRemaining = c.awaitNanos(timeoutNanos); assertTrue(nanosRemaining > timeoutNanos / 2); assertTrue(nanosRemaining <= timeoutNanos); break; case awaitUntil: assertTrue(c.awaitUntil(delayedDate(timeoutMillis))); break; default: throw new AssertionError(); } } /** * Constructor sets given fairness, and is in unlocked state */ public void testConstructor() { PublicReentrantReadWriteLock lock; lock = new PublicReentrantReadWriteLock(); assertFalse(lock.isFair()); assertNotWriteLocked(lock); assertEquals(0, lock.getReadLockCount()); lock = new PublicReentrantReadWriteLock(true); assertTrue(lock.isFair()); assertNotWriteLocked(lock); assertEquals(0, lock.getReadLockCount()); lock = new PublicReentrantReadWriteLock(false); assertFalse(lock.isFair()); assertNotWriteLocked(lock); assertEquals(0, lock.getReadLockCount()); } /** * write-locking and read-locking an unlocked lock succeed */ public void testLock() { testLock(false); } public void testLock_fair() { testLock(true); } public void testLock(boolean fair) { PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); assertNotWriteLocked(lock); lock.writeLock().lock(); assertWriteLockedByMoi(lock); lock.writeLock().unlock(); assertNotWriteLocked(lock); assertEquals(0, lock.getReadLockCount()); lock.readLock().lock(); assertNotWriteLocked(lock); assertEquals(1, lock.getReadLockCount()); lock.readLock().unlock(); assertNotWriteLocked(lock); assertEquals(0, lock.getReadLockCount()); } /** * getWriteHoldCount returns number of recursive holds */ public void testGetWriteHoldCount() { testGetWriteHoldCount(false); } public void testGetWriteHoldCount_fair() { testGetWriteHoldCount(true); } public void testGetWriteHoldCount(boolean fair) { ReentrantReadWriteLock lock = new ReentrantReadWriteLock(fair); for (int i = 1; i <= SIZE; i++) { lock.writeLock().lock(); assertEquals(i,lock.getWriteHoldCount()); } for (int i = SIZE; i > 0; i--) { lock.writeLock().unlock(); assertEquals(i - 1,lock.getWriteHoldCount()); } } /** * writelock.getHoldCount returns number of recursive holds */ public void testGetHoldCount() { testGetHoldCount(false); } public void testGetHoldCount_fair() { testGetHoldCount(true); } public void testGetHoldCount(boolean fair) { ReentrantReadWriteLock lock = new ReentrantReadWriteLock(fair); for (int i = 1; i <= SIZE; i++) { lock.writeLock().lock(); assertEquals(i,lock.writeLock().getHoldCount()); } for (int i = SIZE; i > 0; i--) { lock.writeLock().unlock(); assertEquals(i - 1,lock.writeLock().getHoldCount()); } } /** * getReadHoldCount returns number of recursive holds */ public void testGetReadHoldCount() { testGetReadHoldCount(false); } public void testGetReadHoldCount_fair() { testGetReadHoldCount(true); } public void testGetReadHoldCount(boolean fair) { ReentrantReadWriteLock lock = new ReentrantReadWriteLock(fair); for (int i = 1; i <= SIZE; i++) { lock.readLock().lock(); assertEquals(i,lock.getReadHoldCount()); } for (int i = SIZE; i > 0; i--) { lock.readLock().unlock(); assertEquals(i - 1,lock.getReadHoldCount()); } } /** * write-unlocking an unlocked lock throws IllegalMonitorStateException */ public void testWriteUnlock_IMSE() { testWriteUnlock_IMSE(false); } public void testWriteUnlock_IMSE_fair() { testWriteUnlock_IMSE(true); } public void testWriteUnlock_IMSE(boolean fair) { ReentrantReadWriteLock lock = new ReentrantReadWriteLock(fair); try { lock.writeLock().unlock(); shouldThrow(); } catch (IllegalMonitorStateException success) {} } /** * read-unlocking an unlocked lock throws IllegalMonitorStateException */ public void testReadUnlock_IMSE() { testReadUnlock_IMSE(false); } public void testReadUnlock_IMSE_fair() { testReadUnlock_IMSE(true); } public void testReadUnlock_IMSE(boolean fair) { ReentrantReadWriteLock lock = new ReentrantReadWriteLock(fair); try { lock.readLock().unlock(); shouldThrow(); } catch (IllegalMonitorStateException success) {} } /** * write-lockInterruptibly is interruptible */ public void testWriteLockInterruptibly_Interruptible() { testWriteLockInterruptibly_Interruptible(false); } public void testWriteLockInterruptibly_Interruptible_fair() { testWriteLockInterruptibly_Interruptible(true); } public void testWriteLockInterruptibly_Interruptible(boolean fair) { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); lock.writeLock().lock(); Thread t = newStartedThread(new CheckedInterruptedRunnable() { public void realRun() throws InterruptedException { lock.writeLock().lockInterruptibly(); }}); waitForQueuedThread(lock, t); t.interrupt(); awaitTermination(t); releaseWriteLock(lock); } /** * timed write-tryLock is interruptible */ public void testWriteTryLock_Interruptible() { testWriteTryLock_Interruptible(false); } public void testWriteTryLock_Interruptible_fair() { testWriteTryLock_Interruptible(true); } public void testWriteTryLock_Interruptible(boolean fair) { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); lock.writeLock().lock(); Thread t = newStartedThread(new CheckedInterruptedRunnable() { public void realRun() throws InterruptedException { lock.writeLock().tryLock(2 * LONG_DELAY_MS, MILLISECONDS); }}); waitForQueuedThread(lock, t); t.interrupt(); awaitTermination(t); releaseWriteLock(lock); } /** * read-lockInterruptibly is interruptible */ public void testReadLockInterruptibly_Interruptible() { testReadLockInterruptibly_Interruptible(false); } public void testReadLockInterruptibly_Interruptible_fair() { testReadLockInterruptibly_Interruptible(true); } public void testReadLockInterruptibly_Interruptible(boolean fair) { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); lock.writeLock().lock(); Thread t = newStartedThread(new CheckedInterruptedRunnable() { public void realRun() throws InterruptedException { lock.readLock().lockInterruptibly(); }}); waitForQueuedThread(lock, t); t.interrupt(); awaitTermination(t); releaseWriteLock(lock); } /** * timed read-tryLock is interruptible */ public void testReadTryLock_Interruptible() { testReadTryLock_Interruptible(false); } public void testReadTryLock_Interruptible_fair() { testReadTryLock_Interruptible(true); } public void testReadTryLock_Interruptible(boolean fair) { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); lock.writeLock().lock(); Thread t = newStartedThread(new CheckedInterruptedRunnable() { public void realRun() throws InterruptedException { lock.readLock().tryLock(2 * LONG_DELAY_MS, MILLISECONDS); }}); waitForQueuedThread(lock, t); t.interrupt(); awaitTermination(t); releaseWriteLock(lock); } /** * write-tryLock on an unlocked lock succeeds */ public void testWriteTryLock() { testWriteTryLock(false); } public void testWriteTryLock_fair() { testWriteTryLock(true); } public void testWriteTryLock(boolean fair) { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); assertTrue(lock.writeLock().tryLock()); assertWriteLockedByMoi(lock); assertTrue(lock.writeLock().tryLock()); assertWriteLockedByMoi(lock); lock.writeLock().unlock(); releaseWriteLock(lock); } /** * write-tryLock fails if locked */ public void testWriteTryLockWhenLocked() { testWriteTryLockWhenLocked(false); } public void testWriteTryLockWhenLocked_fair() { testWriteTryLockWhenLocked(true); } public void testWriteTryLockWhenLocked(boolean fair) { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); lock.writeLock().lock(); Thread t = newStartedThread(new CheckedRunnable() { public void realRun() { assertFalse(lock.writeLock().tryLock()); }}); awaitTermination(t); releaseWriteLock(lock); } /** * read-tryLock fails if locked */ public void testReadTryLockWhenLocked() { testReadTryLockWhenLocked(false); } public void testReadTryLockWhenLocked_fair() { testReadTryLockWhenLocked(true); } public void testReadTryLockWhenLocked(boolean fair) { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); lock.writeLock().lock(); Thread t = newStartedThread(new CheckedRunnable() { public void realRun() { assertFalse(lock.readLock().tryLock()); }}); awaitTermination(t); releaseWriteLock(lock); } /** * Multiple threads can hold a read lock when not write-locked */ public void testMultipleReadLocks() { testMultipleReadLocks(false); } public void testMultipleReadLocks_fair() { testMultipleReadLocks(true); } public void testMultipleReadLocks(boolean fair) { final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(fair); lock.readLock().lock(); Thread t = newStartedThread(new CheckedRunnable() { public void realRun() throws InterruptedException { assertTrue(lock.readLock().tryLock()); lock.readLock().unlock(); assertTrue(lock.readLock().tryLock(LONG_DELAY_MS, MILLISECONDS)); lock.readLock().unlock(); lock.readLock().lock(); lock.readLock().unlock(); }}); awaitTermination(t); lock.readLock().unlock(); } /** * A writelock succeeds only after a reading thread unlocks */ public void testWriteAfterReadLock() { testWriteAfterReadLock(false); } public void testWriteAfterReadLock_fair() { testWriteAfterReadLock(true); } public void testWriteAfterReadLock(boolean fair) { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); lock.readLock().lock(); Thread t = newStartedThread(new CheckedRunnable() { public void realRun() { assertEquals(1, lock.getReadLockCount()); lock.writeLock().lock(); assertEquals(0, lock.getReadLockCount()); lock.writeLock().unlock(); }}); waitForQueuedThread(lock, t); assertNotWriteLocked(lock); assertEquals(1, lock.getReadLockCount()); lock.readLock().unlock(); assertEquals(0, lock.getReadLockCount()); awaitTermination(t); assertNotWriteLocked(lock); } /** * A writelock succeeds only after reading threads unlock */ public void testWriteAfterMultipleReadLocks() { testWriteAfterMultipleReadLocks(false); } public void testWriteAfterMultipleReadLocks_fair() { testWriteAfterMultipleReadLocks(true); } public void testWriteAfterMultipleReadLocks(boolean fair) { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); lock.readLock().lock(); lock.readLock().lock(); Thread t1 = newStartedThread(new CheckedRunnable() { public void realRun() { lock.readLock().lock(); assertEquals(3, lock.getReadLockCount()); lock.readLock().unlock(); }}); awaitTermination(t1); Thread t2 = newStartedThread(new CheckedRunnable() { public void realRun() { assertEquals(2, lock.getReadLockCount()); lock.writeLock().lock(); assertEquals(0, lock.getReadLockCount()); lock.writeLock().unlock(); }}); waitForQueuedThread(lock, t2); assertNotWriteLocked(lock); assertEquals(2, lock.getReadLockCount()); lock.readLock().unlock(); lock.readLock().unlock(); assertEquals(0, lock.getReadLockCount()); awaitTermination(t2); assertNotWriteLocked(lock); } /** * A thread that tries to acquire a fair read lock (non-reentrantly) * will block if there is a waiting writer thread */ public void testReaderWriterReaderFairFifo() { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(true); final AtomicBoolean t1GotLock = new AtomicBoolean(false); lock.readLock().lock(); Thread t1 = newStartedThread(new CheckedRunnable() { public void realRun() { assertEquals(1, lock.getReadLockCount()); lock.writeLock().lock(); assertEquals(0, lock.getReadLockCount()); t1GotLock.set(true); lock.writeLock().unlock(); }}); waitForQueuedThread(lock, t1); Thread t2 = newStartedThread(new CheckedRunnable() { public void realRun() { assertEquals(1, lock.getReadLockCount()); lock.readLock().lock(); assertEquals(1, lock.getReadLockCount()); assertTrue(t1GotLock.get()); lock.readLock().unlock(); }}); waitForQueuedThread(lock, t2); assertTrue(t1.isAlive()); assertNotWriteLocked(lock); assertEquals(1, lock.getReadLockCount()); lock.readLock().unlock(); awaitTermination(t1); awaitTermination(t2); assertNotWriteLocked(lock); } /** * Readlocks succeed only after a writing thread unlocks */ public void testReadAfterWriteLock() { testReadAfterWriteLock(false); } public void testReadAfterWriteLock_fair() { testReadAfterWriteLock(true); } public void testReadAfterWriteLock(boolean fair) { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); lock.writeLock().lock(); Thread t1 = newStartedThread(new CheckedRunnable() { public void realRun() { lock.readLock().lock(); lock.readLock().unlock(); }}); Thread t2 = newStartedThread(new CheckedRunnable() { public void realRun() { lock.readLock().lock(); lock.readLock().unlock(); }}); waitForQueuedThread(lock, t1); waitForQueuedThread(lock, t2); releaseWriteLock(lock); awaitTermination(t1); awaitTermination(t2); } /** * Read trylock succeeds if write locked by current thread */ public void testReadHoldingWriteLock() { testReadHoldingWriteLock(false); } public void testReadHoldingWriteLock_fair() { testReadHoldingWriteLock(true); } public void testReadHoldingWriteLock(boolean fair) { final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(fair); lock.writeLock().lock(); assertTrue(lock.readLock().tryLock()); lock.readLock().unlock(); lock.writeLock().unlock(); } /** * Read trylock succeeds (barging) even in the presence of waiting * readers and/or writers */ public void testReadTryLockBarging() { testReadTryLockBarging(false); } public void testReadTryLockBarging_fair() { testReadTryLockBarging(true); } public void testReadTryLockBarging(boolean fair) { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); lock.readLock().lock(); Thread t1 = newStartedThread(new CheckedRunnable() { public void realRun() { lock.writeLock().lock(); lock.writeLock().unlock(); }}); waitForQueuedThread(lock, t1); Thread t2 = newStartedThread(new CheckedRunnable() { public void realRun() { lock.readLock().lock(); lock.readLock().unlock(); }}); if (fair) waitForQueuedThread(lock, t2); Thread t3 = newStartedThread(new CheckedRunnable() { public void realRun() { lock.readLock().tryLock(); lock.readLock().unlock(); }}); assertTrue(lock.getReadLockCount() > 0); awaitTermination(t3); assertTrue(t1.isAlive()); if (fair) assertTrue(t2.isAlive()); lock.readLock().unlock(); awaitTermination(t1); awaitTermination(t2); } /** * Read lock succeeds if write locked by current thread even if * other threads are waiting for readlock */ public void testReadHoldingWriteLock2() { testReadHoldingWriteLock2(false); } public void testReadHoldingWriteLock2_fair() { testReadHoldingWriteLock2(true); } public void testReadHoldingWriteLock2(boolean fair) { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); lock.writeLock().lock(); lock.readLock().lock(); lock.readLock().unlock(); Thread t1 = newStartedThread(new CheckedRunnable() { public void realRun() { lock.readLock().lock(); lock.readLock().unlock(); }}); Thread t2 = newStartedThread(new CheckedRunnable() { public void realRun() { lock.readLock().lock(); lock.readLock().unlock(); }}); waitForQueuedThread(lock, t1); waitForQueuedThread(lock, t2); assertWriteLockedByMoi(lock); lock.readLock().lock(); lock.readLock().unlock(); releaseWriteLock(lock); awaitTermination(t1); awaitTermination(t2); } /** * Read lock succeeds if write locked by current thread even if * other threads are waiting for writelock */ public void testReadHoldingWriteLock3() { testReadHoldingWriteLock3(false); } public void testReadHoldingWriteLock3_fair() { testReadHoldingWriteLock3(true); } public void testReadHoldingWriteLock3(boolean fair) { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); lock.writeLock().lock(); lock.readLock().lock(); lock.readLock().unlock(); Thread t1 = newStartedThread(new CheckedRunnable() { public void realRun() { lock.writeLock().lock(); lock.writeLock().unlock(); }}); Thread t2 = newStartedThread(new CheckedRunnable() { public void realRun() { lock.writeLock().lock(); lock.writeLock().unlock(); }}); waitForQueuedThread(lock, t1); waitForQueuedThread(lock, t2); assertWriteLockedByMoi(lock); lock.readLock().lock(); lock.readLock().unlock(); assertWriteLockedByMoi(lock); lock.writeLock().unlock(); awaitTermination(t1); awaitTermination(t2); } /** * Write lock succeeds if write locked by current thread even if * other threads are waiting for writelock */ public void testWriteHoldingWriteLock4() { testWriteHoldingWriteLock4(false); } public void testWriteHoldingWriteLock4_fair() { testWriteHoldingWriteLock4(true); } public void testWriteHoldingWriteLock4(boolean fair) { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); lock.writeLock().lock(); lock.writeLock().lock(); lock.writeLock().unlock(); Thread t1 = newStartedThread(new CheckedRunnable() { public void realRun() { lock.writeLock().lock(); lock.writeLock().unlock(); }}); Thread t2 = newStartedThread(new CheckedRunnable() { public void realRun() { lock.writeLock().lock(); lock.writeLock().unlock(); }}); waitForQueuedThread(lock, t1); waitForQueuedThread(lock, t2); assertWriteLockedByMoi(lock); assertEquals(1, lock.getWriteHoldCount()); lock.writeLock().lock(); assertWriteLockedByMoi(lock); assertEquals(2, lock.getWriteHoldCount()); lock.writeLock().unlock(); assertWriteLockedByMoi(lock); assertEquals(1, lock.getWriteHoldCount()); lock.writeLock().unlock(); awaitTermination(t1); awaitTermination(t2); } /** * Read tryLock succeeds if readlocked but not writelocked */ public void testTryLockWhenReadLocked() { testTryLockWhenReadLocked(false); } public void testTryLockWhenReadLocked_fair() { testTryLockWhenReadLocked(true); } public void testTryLockWhenReadLocked(boolean fair) { final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(fair); lock.readLock().lock(); Thread t = newStartedThread(new CheckedRunnable() { public void realRun() { assertTrue(lock.readLock().tryLock()); lock.readLock().unlock(); }}); awaitTermination(t); lock.readLock().unlock(); } /** * write tryLock fails when readlocked */ public void testWriteTryLockWhenReadLocked() { testWriteTryLockWhenReadLocked(false); } public void testWriteTryLockWhenReadLocked_fair() { testWriteTryLockWhenReadLocked(true); } public void testWriteTryLockWhenReadLocked(boolean fair) { final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(fair); lock.readLock().lock(); Thread t = newStartedThread(new CheckedRunnable() { public void realRun() { assertFalse(lock.writeLock().tryLock()); }}); awaitTermination(t); lock.readLock().unlock(); } /** * write timed tryLock times out if locked */ public void testWriteTryLock_Timeout() { testWriteTryLock_Timeout(false); } public void testWriteTryLock_Timeout_fair() { testWriteTryLock_Timeout(true); } public void testWriteTryLock_Timeout(boolean fair) { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); lock.writeLock().lock(); Thread t = newStartedThread(new CheckedRunnable() { public void realRun() throws InterruptedException { long startTime = System.nanoTime(); long timeoutMillis = 10; assertFalse(lock.writeLock().tryLock(timeoutMillis, MILLISECONDS)); assertTrue(millisElapsedSince(startTime) >= timeoutMillis); }}); awaitTermination(t); releaseWriteLock(lock); } /** * read timed tryLock times out if write-locked */ public void testReadTryLock_Timeout() { testReadTryLock_Timeout(false); } public void testReadTryLock_Timeout_fair() { testReadTryLock_Timeout(true); } public void testReadTryLock_Timeout(boolean fair) { final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(fair); lock.writeLock().lock(); Thread t = newStartedThread(new CheckedRunnable() { public void realRun() throws InterruptedException { long startTime = System.nanoTime(); long timeoutMillis = 10; assertFalse(lock.readLock().tryLock(timeoutMillis, MILLISECONDS)); assertTrue(millisElapsedSince(startTime) >= timeoutMillis); }}); awaitTermination(t); assertTrue(lock.writeLock().isHeldByCurrentThread()); lock.writeLock().unlock(); } /** * write lockInterruptibly succeeds if unlocked, else is interruptible */ public void testWriteLockInterruptibly() { testWriteLockInterruptibly(false); } public void testWriteLockInterruptibly_fair() { testWriteLockInterruptibly(true); } public void testWriteLockInterruptibly(boolean fair) { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); try { lock.writeLock().lockInterruptibly(); } catch (InterruptedException fail) { threadUnexpectedException(fail); } Thread t = newStartedThread(new CheckedInterruptedRunnable() { public void realRun() throws InterruptedException { lock.writeLock().lockInterruptibly(); }}); waitForQueuedThread(lock, t); t.interrupt(); assertTrue(lock.writeLock().isHeldByCurrentThread()); awaitTermination(t); releaseWriteLock(lock); } /** * read lockInterruptibly succeeds if lock free else is interruptible */ public void testReadLockInterruptibly() { testReadLockInterruptibly(false); } public void testReadLockInterruptibly_fair() { testReadLockInterruptibly(true); } public void testReadLockInterruptibly(boolean fair) { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); try { lock.readLock().lockInterruptibly(); lock.readLock().unlock(); lock.writeLock().lockInterruptibly(); } catch (InterruptedException fail) { threadUnexpectedException(fail); } Thread t = newStartedThread(new CheckedInterruptedRunnable() { public void realRun() throws InterruptedException { lock.readLock().lockInterruptibly(); }}); waitForQueuedThread(lock, t); t.interrupt(); awaitTermination(t); releaseWriteLock(lock); } /** * Calling await without holding lock throws IllegalMonitorStateException */ public void testAwait_IMSE() { testAwait_IMSE(false); } public void testAwait_IMSE_fair() { testAwait_IMSE(true); } public void testAwait_IMSE(boolean fair) { final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(fair); final Condition c = lock.writeLock().newCondition(); for (AwaitMethod awaitMethod : AwaitMethod.values()) { long startTime = System.nanoTime(); try { await(c, awaitMethod); shouldThrow(); } catch (IllegalMonitorStateException success) { } catch (InterruptedException fail) { threadUnexpectedException(fail); } assertTrue(millisElapsedSince(startTime) < LONG_DELAY_MS); } } /** * Calling signal without holding lock throws IllegalMonitorStateException */ public void testSignal_IMSE() { testSignal_IMSE(false); } public void testSignal_IMSE_fair() { testSignal_IMSE(true); } public void testSignal_IMSE(boolean fair) { final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(fair); final Condition c = lock.writeLock().newCondition(); try { c.signal(); shouldThrow(); } catch (IllegalMonitorStateException success) {} } /** * Calling signalAll without holding lock throws IllegalMonitorStateException */ public void testSignalAll_IMSE() { testSignalAll_IMSE(false); } public void testSignalAll_IMSE_fair() { testSignalAll_IMSE(true); } public void testSignalAll_IMSE(boolean fair) { final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(fair); final Condition c = lock.writeLock().newCondition(); try { c.signalAll(); shouldThrow(); } catch (IllegalMonitorStateException success) {} } /** * awaitNanos without a signal times out */ public void testAwaitNanos_Timeout() { testAwaitNanos_Timeout(false); } public void testAwaitNanos_Timeout_fair() { testAwaitNanos_Timeout(true); } public void testAwaitNanos_Timeout(boolean fair) { try { final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(fair); final Condition c = lock.writeLock().newCondition(); lock.writeLock().lock(); long startTime = System.nanoTime(); long timeoutMillis = 10; long timeoutNanos = MILLISECONDS.toNanos(timeoutMillis); long nanosRemaining = c.awaitNanos(timeoutNanos); assertTrue(nanosRemaining <= 0); assertTrue(millisElapsedSince(startTime) >= timeoutMillis); lock.writeLock().unlock(); } catch (InterruptedException fail) { threadUnexpectedException(fail); } } /** * timed await without a signal times out */ public void testAwait_Timeout() { testAwait_Timeout(false); } public void testAwait_Timeout_fair() { testAwait_Timeout(true); } public void testAwait_Timeout(boolean fair) { try { final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(fair); final Condition c = lock.writeLock().newCondition(); lock.writeLock().lock(); long startTime = System.nanoTime(); long timeoutMillis = 10; assertFalse(c.await(timeoutMillis, MILLISECONDS)); assertTrue(millisElapsedSince(startTime) >= timeoutMillis); lock.writeLock().unlock(); } catch (InterruptedException fail) { threadUnexpectedException(fail); } } /** * awaitUntil without a signal times out */ public void testAwaitUntil_Timeout() { testAwaitUntil_Timeout(false); } public void testAwaitUntil_Timeout_fair() { testAwaitUntil_Timeout(true); } public void testAwaitUntil_Timeout(boolean fair) { try { final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(fair); final Condition c = lock.writeLock().newCondition(); lock.writeLock().lock(); // We shouldn't assume that nanoTime and currentTimeMillis // use the same time source, so don't use nanoTime here. java.util.Date delayedDate = delayedDate(timeoutMillis()); assertFalse(c.awaitUntil(delayedDate)); assertTrue(new java.util.Date().getTime() >= delayedDate.getTime()); lock.writeLock().unlock(); } catch (InterruptedException fail) { threadUnexpectedException(fail); } } /** * await returns when signalled */ public void testAwait() { testAwait(false); } public void testAwait_fair() { testAwait(true); } public void testAwait(boolean fair) { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); final Condition c = lock.writeLock().newCondition(); final CountDownLatch locked = new CountDownLatch(1); Thread t = newStartedThread(new CheckedRunnable() { public void realRun() throws InterruptedException { lock.writeLock().lock(); locked.countDown(); c.await(); lock.writeLock().unlock(); }}); await(locked); lock.writeLock().lock(); assertHasWaiters(lock, c, t); c.signal(); assertHasNoWaiters(lock, c); assertTrue(t.isAlive()); lock.writeLock().unlock(); awaitTermination(t); } /** * awaitUninterruptibly is uninterruptible */ public void testAwaitUninterruptibly() { testAwaitUninterruptibly(false); } public void testAwaitUninterruptibly_fair() { testAwaitUninterruptibly(true); } public void testAwaitUninterruptibly(boolean fair) { final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(fair); final Condition c = lock.writeLock().newCondition(); final CountDownLatch pleaseInterrupt = new CountDownLatch(2); Thread t1 = newStartedThread(new CheckedRunnable() { public void realRun() { // Interrupt before awaitUninterruptibly lock.writeLock().lock(); pleaseInterrupt.countDown(); Thread.currentThread().interrupt(); c.awaitUninterruptibly(); assertTrue(Thread.interrupted()); lock.writeLock().unlock(); }}); Thread t2 = newStartedThread(new CheckedRunnable() { public void realRun() { // Interrupt during awaitUninterruptibly lock.writeLock().lock(); pleaseInterrupt.countDown(); c.awaitUninterruptibly(); assertTrue(Thread.interrupted()); lock.writeLock().unlock(); }}); await(pleaseInterrupt); lock.writeLock().lock(); lock.writeLock().unlock(); t2.interrupt(); assertThreadStaysAlive(t1); assertTrue(t2.isAlive()); lock.writeLock().lock(); c.signalAll(); lock.writeLock().unlock(); awaitTermination(t1); awaitTermination(t2); } /** * await/awaitNanos/awaitUntil is interruptible */ public void testInterruptible_await() { testInterruptible(false, AwaitMethod.await); } public void testInterruptible_await_fair() { testInterruptible(true, AwaitMethod.await); } public void testInterruptible_awaitTimed() { testInterruptible(false, AwaitMethod.awaitTimed); } public void testInterruptible_awaitTimed_fair() { testInterruptible(true, AwaitMethod.awaitTimed); } public void testInterruptible_awaitNanos() { testInterruptible(false, AwaitMethod.awaitNanos); } public void testInterruptible_awaitNanos_fair() { testInterruptible(true, AwaitMethod.awaitNanos); } public void testInterruptible_awaitUntil() { testInterruptible(false, AwaitMethod.awaitUntil); } public void testInterruptible_awaitUntil_fair() { testInterruptible(true, AwaitMethod.awaitUntil); } public void testInterruptible(boolean fair, final AwaitMethod awaitMethod) { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); final Condition c = lock.writeLock().newCondition(); final CountDownLatch locked = new CountDownLatch(1); Thread t = newStartedThread(new CheckedInterruptedRunnable() { public void realRun() throws InterruptedException { lock.writeLock().lock(); assertWriteLockedByMoi(lock); assertHasNoWaiters(lock, c); locked.countDown(); try { await(c, awaitMethod); } finally { assertWriteLockedByMoi(lock); assertHasNoWaiters(lock, c); lock.writeLock().unlock(); assertFalse(Thread.interrupted()); } }}); await(locked); assertHasWaiters(lock, c, t); t.interrupt(); awaitTermination(t); assertNotWriteLocked(lock); } /** * signalAll wakes up all threads */ public void testSignalAll_await() { testSignalAll(false, AwaitMethod.await); } public void testSignalAll_await_fair() { testSignalAll(true, AwaitMethod.await); } public void testSignalAll_awaitTimed() { testSignalAll(false, AwaitMethod.awaitTimed); } public void testSignalAll_awaitTimed_fair() { testSignalAll(true, AwaitMethod.awaitTimed); } public void testSignalAll_awaitNanos() { testSignalAll(false, AwaitMethod.awaitNanos); } public void testSignalAll_awaitNanos_fair() { testSignalAll(true, AwaitMethod.awaitNanos); } public void testSignalAll_awaitUntil() { testSignalAll(false, AwaitMethod.awaitUntil); } public void testSignalAll_awaitUntil_fair() { testSignalAll(true, AwaitMethod.awaitUntil); } public void testSignalAll(boolean fair, final AwaitMethod awaitMethod) { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); final Condition c = lock.writeLock().newCondition(); final CountDownLatch locked = new CountDownLatch(2); final Lock writeLock = lock.writeLock(); class Awaiter extends CheckedRunnable { public void realRun() throws InterruptedException { writeLock.lock(); locked.countDown(); await(c, awaitMethod); writeLock.unlock(); } } Thread t1 = newStartedThread(new Awaiter()); Thread t2 = newStartedThread(new Awaiter()); await(locked); writeLock.lock(); assertHasWaiters(lock, c, t1, t2); c.signalAll(); assertHasNoWaiters(lock, c); writeLock.unlock(); awaitTermination(t1); awaitTermination(t2); } /** * signal wakes up waiting threads in FIFO order */ public void testSignalWakesFifo() { testSignalWakesFifo(false); } public void testSignalWakesFifo_fair() { testSignalWakesFifo(true); } public void testSignalWakesFifo(boolean fair) { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); final Condition c = lock.writeLock().newCondition(); final CountDownLatch locked1 = new CountDownLatch(1); final CountDownLatch locked2 = new CountDownLatch(1); final Lock writeLock = lock.writeLock(); Thread t1 = newStartedThread(new CheckedRunnable() { public void realRun() throws InterruptedException { writeLock.lock(); locked1.countDown(); c.await(); writeLock.unlock(); }}); await(locked1); Thread t2 = newStartedThread(new CheckedRunnable() { public void realRun() throws InterruptedException { writeLock.lock(); locked2.countDown(); c.await(); writeLock.unlock(); }}); await(locked2); writeLock.lock(); assertHasWaiters(lock, c, t1, t2); assertFalse(lock.hasQueuedThreads()); c.signal(); assertHasWaiters(lock, c, t2); assertTrue(lock.hasQueuedThread(t1)); assertFalse(lock.hasQueuedThread(t2)); c.signal(); assertHasNoWaiters(lock, c); assertTrue(lock.hasQueuedThread(t1)); assertTrue(lock.hasQueuedThread(t2)); writeLock.unlock(); awaitTermination(t1); awaitTermination(t2); } /** * await after multiple reentrant locking preserves lock count */ public void testAwaitLockCount() { testAwaitLockCount(false); } public void testAwaitLockCount_fair() { testAwaitLockCount(true); } public void testAwaitLockCount(boolean fair) { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); final Condition c = lock.writeLock().newCondition(); final CountDownLatch locked = new CountDownLatch(2); Thread t1 = newStartedThread(new CheckedRunnable() { public void realRun() throws InterruptedException { lock.writeLock().lock(); assertWriteLockedByMoi(lock); assertEquals(1, lock.writeLock().getHoldCount()); locked.countDown(); c.await(); assertWriteLockedByMoi(lock); assertEquals(1, lock.writeLock().getHoldCount()); lock.writeLock().unlock(); }}); Thread t2 = newStartedThread(new CheckedRunnable() { public void realRun() throws InterruptedException { lock.writeLock().lock(); lock.writeLock().lock(); assertWriteLockedByMoi(lock); assertEquals(2, lock.writeLock().getHoldCount()); locked.countDown(); c.await(); assertWriteLockedByMoi(lock); assertEquals(2, lock.writeLock().getHoldCount()); lock.writeLock().unlock(); lock.writeLock().unlock(); }}); await(locked); lock.writeLock().lock(); assertHasWaiters(lock, c, t1, t2); c.signalAll(); assertHasNoWaiters(lock, c); lock.writeLock().unlock(); awaitTermination(t1); awaitTermination(t2); } /** * A serialized lock deserializes as unlocked */ public void testSerialization() { testSerialization(false); } public void testSerialization_fair() { testSerialization(true); } public void testSerialization(boolean fair) { ReentrantReadWriteLock lock = new ReentrantReadWriteLock(fair); lock.writeLock().lock(); lock.readLock().lock(); ReentrantReadWriteLock clone = serialClone(lock); assertEquals(lock.isFair(), clone.isFair()); assertTrue(lock.isWriteLocked()); assertFalse(clone.isWriteLocked()); assertEquals(1, lock.getReadLockCount()); assertEquals(0, clone.getReadLockCount()); clone.writeLock().lock(); clone.readLock().lock(); assertTrue(clone.isWriteLocked()); assertEquals(1, clone.getReadLockCount()); clone.readLock().unlock(); clone.writeLock().unlock(); assertFalse(clone.isWriteLocked()); assertEquals(1, lock.getReadLockCount()); assertEquals(0, clone.getReadLockCount()); } /** * hasQueuedThreads reports whether there are waiting threads */ public void testHasQueuedThreads() { testHasQueuedThreads(false); } public void testHasQueuedThreads_fair() { testHasQueuedThreads(true); } public void testHasQueuedThreads(boolean fair) { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); Thread t1 = new Thread(new InterruptedLockRunnable(lock)); Thread t2 = new Thread(new InterruptibleLockRunnable(lock)); assertFalse(lock.hasQueuedThreads()); lock.writeLock().lock(); assertFalse(lock.hasQueuedThreads()); t1.start(); waitForQueuedThread(lock, t1); assertTrue(lock.hasQueuedThreads()); t2.start(); waitForQueuedThread(lock, t2); assertTrue(lock.hasQueuedThreads()); t1.interrupt(); awaitTermination(t1); assertTrue(lock.hasQueuedThreads()); lock.writeLock().unlock(); awaitTermination(t2); assertFalse(lock.hasQueuedThreads()); } /** * hasQueuedThread(null) throws NPE */ public void testHasQueuedThreadNPE() { testHasQueuedThreadNPE(false); } public void testHasQueuedThreadNPE_fair() { testHasQueuedThreadNPE(true); } public void testHasQueuedThreadNPE(boolean fair) { final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(fair); try { lock.hasQueuedThread(null); shouldThrow(); } catch (NullPointerException success) {} } /** * hasQueuedThread reports whether a thread is queued */ public void testHasQueuedThread() { testHasQueuedThread(false); } public void testHasQueuedThread_fair() { testHasQueuedThread(true); } public void testHasQueuedThread(boolean fair) { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); Thread t1 = new Thread(new InterruptedLockRunnable(lock)); Thread t2 = new Thread(new InterruptibleLockRunnable(lock)); assertFalse(lock.hasQueuedThread(t1)); assertFalse(lock.hasQueuedThread(t2)); lock.writeLock().lock(); t1.start(); waitForQueuedThread(lock, t1); assertTrue(lock.hasQueuedThread(t1)); assertFalse(lock.hasQueuedThread(t2)); t2.start(); waitForQueuedThread(lock, t2); assertTrue(lock.hasQueuedThread(t1)); assertTrue(lock.hasQueuedThread(t2)); t1.interrupt(); awaitTermination(t1); assertFalse(lock.hasQueuedThread(t1)); assertTrue(lock.hasQueuedThread(t2)); lock.writeLock().unlock(); awaitTermination(t2); assertFalse(lock.hasQueuedThread(t1)); assertFalse(lock.hasQueuedThread(t2)); } /** * getQueueLength reports number of waiting threads */ public void testGetQueueLength() { testGetQueueLength(false); } public void testGetQueueLength_fair() { testGetQueueLength(true); } public void testGetQueueLength(boolean fair) { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); Thread t1 = new Thread(new InterruptedLockRunnable(lock)); Thread t2 = new Thread(new InterruptibleLockRunnable(lock)); assertEquals(0, lock.getQueueLength()); lock.writeLock().lock(); t1.start(); waitForQueuedThread(lock, t1); assertEquals(1, lock.getQueueLength()); t2.start(); waitForQueuedThread(lock, t2); assertEquals(2, lock.getQueueLength()); t1.interrupt(); awaitTermination(t1); assertEquals(1, lock.getQueueLength()); lock.writeLock().unlock(); awaitTermination(t2); assertEquals(0, lock.getQueueLength()); } /** * getQueuedThreads includes waiting threads */ public void testGetQueuedThreads() { testGetQueuedThreads(false); } public void testGetQueuedThreads_fair() { testGetQueuedThreads(true); } public void testGetQueuedThreads(boolean fair) { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); Thread t1 = new Thread(new InterruptedLockRunnable(lock)); Thread t2 = new Thread(new InterruptibleLockRunnable(lock)); assertTrue(lock.getQueuedThreads().isEmpty()); lock.writeLock().lock(); assertTrue(lock.getQueuedThreads().isEmpty()); t1.start(); waitForQueuedThread(lock, t1); assertEquals(1, lock.getQueuedThreads().size()); assertTrue(lock.getQueuedThreads().contains(t1)); t2.start(); waitForQueuedThread(lock, t2); assertEquals(2, lock.getQueuedThreads().size()); assertTrue(lock.getQueuedThreads().contains(t1)); assertTrue(lock.getQueuedThreads().contains(t2)); t1.interrupt(); awaitTermination(t1); assertFalse(lock.getQueuedThreads().contains(t1)); assertTrue(lock.getQueuedThreads().contains(t2)); assertEquals(1, lock.getQueuedThreads().size()); lock.writeLock().unlock(); awaitTermination(t2); assertTrue(lock.getQueuedThreads().isEmpty()); } /** * hasWaiters throws NPE if null */ public void testHasWaitersNPE() { testHasWaitersNPE(false); } public void testHasWaitersNPE_fair() { testHasWaitersNPE(true); } public void testHasWaitersNPE(boolean fair) { final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(fair); try { lock.hasWaiters(null); shouldThrow(); } catch (NullPointerException success) {} } /** * getWaitQueueLength throws NPE if null */ public void testGetWaitQueueLengthNPE() { testGetWaitQueueLengthNPE(false); } public void testGetWaitQueueLengthNPE_fair() { testGetWaitQueueLengthNPE(true); } public void testGetWaitQueueLengthNPE(boolean fair) { final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(fair); try { lock.getWaitQueueLength(null); shouldThrow(); } catch (NullPointerException success) {} } /** * getWaitingThreads throws NPE if null */ public void testGetWaitingThreadsNPE() { testGetWaitingThreadsNPE(false); } public void testGetWaitingThreadsNPE_fair() { testGetWaitingThreadsNPE(true); } public void testGetWaitingThreadsNPE(boolean fair) { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); try { lock.getWaitingThreads(null); shouldThrow(); } catch (NullPointerException success) {} } /** * hasWaiters throws IllegalArgumentException if not owned */ public void testHasWaitersIAE() { testHasWaitersIAE(false); } public void testHasWaitersIAE_fair() { testHasWaitersIAE(true); } public void testHasWaitersIAE(boolean fair) { final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(fair); final Condition c = lock.writeLock().newCondition(); final ReentrantReadWriteLock lock2 = new ReentrantReadWriteLock(fair); try { lock2.hasWaiters(c); shouldThrow(); } catch (IllegalArgumentException success) {} } /** * hasWaiters throws IllegalMonitorStateException if not locked */ public void testHasWaitersIMSE() { testHasWaitersIMSE(false); } public void testHasWaitersIMSE_fair() { testHasWaitersIMSE(true); } public void testHasWaitersIMSE(boolean fair) { final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(fair); final Condition c = lock.writeLock().newCondition(); try { lock.hasWaiters(c); shouldThrow(); } catch (IllegalMonitorStateException success) {} } /** * getWaitQueueLength throws IllegalArgumentException if not owned */ public void testGetWaitQueueLengthIAE() { testGetWaitQueueLengthIAE(false); } public void testGetWaitQueueLengthIAE_fair() { testGetWaitQueueLengthIAE(true); } public void testGetWaitQueueLengthIAE(boolean fair) { final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(fair); final Condition c = lock.writeLock().newCondition(); final ReentrantReadWriteLock lock2 = new ReentrantReadWriteLock(fair); try { lock2.getWaitQueueLength(c); shouldThrow(); } catch (IllegalArgumentException success) {} } /** * getWaitQueueLength throws IllegalMonitorStateException if not locked */ public void testGetWaitQueueLengthIMSE() { testGetWaitQueueLengthIMSE(false); } public void testGetWaitQueueLengthIMSE_fair() { testGetWaitQueueLengthIMSE(true); } public void testGetWaitQueueLengthIMSE(boolean fair) { final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(fair); final Condition c = lock.writeLock().newCondition(); try { lock.getWaitQueueLength(c); shouldThrow(); } catch (IllegalMonitorStateException success) {} } /** * getWaitingThreads throws IllegalArgumentException if not owned */ public void testGetWaitingThreadsIAE() { testGetWaitingThreadsIAE(false); } public void testGetWaitingThreadsIAE_fair() { testGetWaitingThreadsIAE(true); } public void testGetWaitingThreadsIAE(boolean fair) { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); final Condition c = lock.writeLock().newCondition(); final PublicReentrantReadWriteLock lock2 = new PublicReentrantReadWriteLock(fair); try { lock2.getWaitingThreads(c); shouldThrow(); } catch (IllegalArgumentException success) {} } /** * getWaitingThreads throws IllegalMonitorStateException if not locked */ public void testGetWaitingThreadsIMSE() { testGetWaitingThreadsIMSE(false); } public void testGetWaitingThreadsIMSE_fair() { testGetWaitingThreadsIMSE(true); } public void testGetWaitingThreadsIMSE(boolean fair) { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); final Condition c = lock.writeLock().newCondition(); try { lock.getWaitingThreads(c); shouldThrow(); } catch (IllegalMonitorStateException success) {} } /** * hasWaiters returns true when a thread is waiting, else false */ public void testHasWaiters() { testHasWaiters(false); } public void testHasWaiters_fair() { testHasWaiters(true); } public void testHasWaiters(boolean fair) { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); final Condition c = lock.writeLock().newCondition(); final CountDownLatch locked = new CountDownLatch(1); Thread t = newStartedThread(new CheckedRunnable() { public void realRun() throws InterruptedException { lock.writeLock().lock(); assertHasNoWaiters(lock, c); assertFalse(lock.hasWaiters(c)); locked.countDown(); c.await(); assertHasNoWaiters(lock, c); assertFalse(lock.hasWaiters(c)); lock.writeLock().unlock(); }}); await(locked); lock.writeLock().lock(); assertHasWaiters(lock, c, t); assertTrue(lock.hasWaiters(c)); c.signal(); assertHasNoWaiters(lock, c); assertFalse(lock.hasWaiters(c)); lock.writeLock().unlock(); awaitTermination(t); assertHasNoWaiters(lock, c); } /** * getWaitQueueLength returns number of waiting threads */ public void testGetWaitQueueLength() { testGetWaitQueueLength(false); } public void testGetWaitQueueLength_fair() { testGetWaitQueueLength(true); } public void testGetWaitQueueLength(boolean fair) { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); final Condition c = lock.writeLock().newCondition(); final CountDownLatch locked = new CountDownLatch(1); Thread t = newStartedThread(new CheckedRunnable() { public void realRun() throws InterruptedException { lock.writeLock().lock(); assertEquals(0, lock.getWaitQueueLength(c)); locked.countDown(); c.await(); lock.writeLock().unlock(); }}); await(locked); lock.writeLock().lock(); assertHasWaiters(lock, c, t); assertEquals(1, lock.getWaitQueueLength(c)); c.signal(); assertHasNoWaiters(lock, c); assertEquals(0, lock.getWaitQueueLength(c)); lock.writeLock().unlock(); awaitTermination(t); } /** * getWaitingThreads returns only and all waiting threads */ public void testGetWaitingThreads() { testGetWaitingThreads(false); } public void testGetWaitingThreads_fair() { testGetWaitingThreads(true); } public void testGetWaitingThreads(boolean fair) { final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(fair); final Condition c = lock.writeLock().newCondition(); final CountDownLatch locked1 = new CountDownLatch(1); final CountDownLatch locked2 = new CountDownLatch(1); Thread t1 = new Thread(new CheckedRunnable() { public void realRun() throws InterruptedException { lock.writeLock().lock(); assertTrue(lock.getWaitingThreads(c).isEmpty()); locked1.countDown(); c.await(); lock.writeLock().unlock(); }}); Thread t2 = new Thread(new CheckedRunnable() { public void realRun() throws InterruptedException { lock.writeLock().lock(); assertFalse(lock.getWaitingThreads(c).isEmpty()); locked2.countDown(); c.await(); lock.writeLock().unlock(); }}); lock.writeLock().lock(); assertTrue(lock.getWaitingThreads(c).isEmpty()); lock.writeLock().unlock(); t1.start(); await(locked1); t2.start(); await(locked2); lock.writeLock().lock(); assertTrue(lock.hasWaiters(c)); assertTrue(lock.getWaitingThreads(c).contains(t1)); assertTrue(lock.getWaitingThreads(c).contains(t2)); assertEquals(2, lock.getWaitingThreads(c).size()); c.signalAll(); assertHasNoWaiters(lock, c); lock.writeLock().unlock(); awaitTermination(t1); awaitTermination(t2); assertHasNoWaiters(lock, c); } /** * toString indicates current lock state */ public void testToString() { testToString(false); } public void testToString_fair() { testToString(true); } public void testToString(boolean fair) { ReentrantReadWriteLock lock = new ReentrantReadWriteLock(fair); assertTrue(lock.toString().contains("Write locks = 0")); assertTrue(lock.toString().contains("Read locks = 0")); lock.writeLock().lock(); assertTrue(lock.toString().contains("Write locks = 1")); assertTrue(lock.toString().contains("Read locks = 0")); lock.writeLock().unlock(); lock.readLock().lock(); lock.readLock().lock(); assertTrue(lock.toString().contains("Write locks = 0")); assertTrue(lock.toString().contains("Read locks = 2")); } /** * readLock.toString indicates current lock state */ public void testReadLockToString() { testReadLockToString(false); } public void testReadLockToString_fair() { testReadLockToString(true); } public void testReadLockToString(boolean fair) { ReentrantReadWriteLock lock = new ReentrantReadWriteLock(fair); assertTrue(lock.readLock().toString().contains("Read locks = 0")); lock.readLock().lock(); lock.readLock().lock(); assertTrue(lock.readLock().toString().contains("Read locks = 2")); } /** * writeLock.toString indicates current lock state */ public void testWriteLockToString() { testWriteLockToString(false); } public void testWriteLockToString_fair() { testWriteLockToString(true); } public void testWriteLockToString(boolean fair) { ReentrantReadWriteLock lock = new ReentrantReadWriteLock(fair); assertTrue(lock.writeLock().toString().contains("Unlocked")); lock.writeLock().lock(); assertTrue(lock.writeLock().toString().contains("Locked")); lock.writeLock().unlock(); assertTrue(lock.writeLock().toString().contains("Unlocked")); } }