--- jsr166/src/test/tck/ReentrantReadWriteLockTest.java 2009/11/17 14:45:32 1.34 +++ jsr166/src/test/tck/ReentrantReadWriteLockTest.java 2014/12/31 19:05:43 1.69 @@ -1,23 +1,32 @@ /* * 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/licenses/publicdomain + * http://creativecommons.org/publicdomain/zero/1.0/ * Other contributors include Andrew Wright, Jeffrey Hayes, * Pat Fisher, Mike Judd. */ -import junit.framework.*; -import java.util.concurrent.locks.*; -import java.util.concurrent.*; -import java.io.*; -import java.util.*; +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) { - junit.textui.TestRunner.run (suite()); + junit.textui.TestRunner.run(suite()); } public static Test suite() { - return new TestSuite(ReentrantReadWriteLockTest.class); + return new TestSuite(ReentrantReadWriteLockTest.class); } /** @@ -31,7 +40,6 @@ public class ReentrantReadWriteLockTest } } - /** * A runnable calling lockInterruptibly that expects to be * interrupted @@ -49,6 +57,10 @@ public class ReentrantReadWriteLockTest */ static class PublicReentrantReadWriteLock extends ReentrantReadWriteLock { PublicReentrantReadWriteLock() { super(); } + PublicReentrantReadWriteLock(boolean fair) { super(fair); } + public Thread getOwner() { + return super.getOwner(); + } public Collection getQueuedThreads() { return super.getQueuedThreads(); } @@ -58,717 +70,831 @@ public class ReentrantReadWriteLockTest } /** - * Constructor sets given fairness, and is in unlocked state + * Releases write lock, checking that it had a hold count of 1. */ - public void testConstructor() { - ReentrantReadWriteLock rl = new ReentrantReadWriteLock(); - assertFalse(rl.isFair()); - assertFalse(rl.isWriteLocked()); - assertEquals(0, rl.getReadLockCount()); - ReentrantReadWriteLock r2 = new ReentrantReadWriteLock(true); - assertTrue(r2.isFair()); - assertFalse(r2.isWriteLocked()); - assertEquals(0, r2.getReadLockCount()); - ReentrantReadWriteLock r3 = new ReentrantReadWriteLock(false); - assertFalse(r3.isFair()); - assertFalse(r3.isWriteLocked()); - assertEquals(0, r3.getReadLockCount()); + void releaseWriteLock(PublicReentrantReadWriteLock lock) { + ReentrantReadWriteLock.WriteLock writeLock = lock.writeLock(); + assertWriteLockedByMoi(lock); + assertEquals(1, lock.getWriteHoldCount()); + writeLock.unlock(); + assertNotWriteLocked(lock); } /** - * write-locking and read-locking an unlocked lock succeed + * 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. */ - public void testLock() { - ReentrantReadWriteLock rl = new ReentrantReadWriteLock(); - rl.writeLock().lock(); - assertTrue(rl.isWriteLocked()); - assertTrue(rl.isWriteLockedByCurrentThread()); - assertTrue(rl.writeLock().isHeldByCurrentThread()); - assertEquals(0, rl.getReadLockCount()); - rl.writeLock().unlock(); - assertFalse(rl.isWriteLocked()); - assertFalse(rl.isWriteLockedByCurrentThread()); - assertFalse(rl.writeLock().isHeldByCurrentThread()); - assertEquals(0, rl.getReadLockCount()); - rl.readLock().lock(); - assertFalse(rl.isWriteLocked()); - assertFalse(rl.isWriteLockedByCurrentThread()); - assertEquals(1, rl.getReadLockCount()); - rl.readLock().unlock(); - assertFalse(rl.isWriteLocked()); - assertFalse(rl.isWriteLockedByCurrentThread()); - assertEquals(0, rl.getReadLockCount()); + 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()); + } /** - * locking an unlocked fair lock succeeds - */ - public void testFairLock() { - ReentrantReadWriteLock rl = new ReentrantReadWriteLock(true); - rl.writeLock().lock(); - assertTrue(rl.isWriteLocked()); - assertTrue(rl.isWriteLockedByCurrentThread()); - assertTrue(rl.writeLock().isHeldByCurrentThread()); - assertEquals(0, rl.getReadLockCount()); - rl.writeLock().unlock(); - assertFalse(rl.isWriteLocked()); - assertFalse(rl.isWriteLockedByCurrentThread()); - assertFalse(rl.writeLock().isHeldByCurrentThread()); - assertEquals(0, rl.getReadLockCount()); - rl.readLock().lock(); - assertFalse(rl.isWriteLocked()); - assertFalse(rl.isWriteLockedByCurrentThread()); - assertEquals(1, rl.getReadLockCount()); - rl.readLock().unlock(); - assertFalse(rl.isWriteLocked()); - assertFalse(rl.isWriteLockedByCurrentThread()); - assertEquals(0, rl.getReadLockCount()); + * 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(lock.getWaitingThreads(c)), + new HashSet(Arrays.asList(threads))); + lock.writeLock().unlock(); + } + + enum AwaitMethod { await, awaitTimed, awaitNanos, awaitUntil } + + /** + * Awaits condition using the specified AwaitMethod. + */ + void await(Condition c, AwaitMethod awaitMethod) + throws InterruptedException { + switch (awaitMethod) { + case await: + c.await(); + break; + case awaitTimed: + assertTrue(c.await(2 * LONG_DELAY_MS, MILLISECONDS)); + break; + case awaitNanos: + long nanosRemaining = c.awaitNanos(MILLISECONDS.toNanos(2 * LONG_DELAY_MS)); + assertTrue(nanosRemaining > 0); + break; + case awaitUntil: + java.util.Date d = new java.util.Date(); + assertTrue(c.awaitUntil(new java.util.Date(d.getTime() + 2 * LONG_DELAY_MS))); + break; + } + } + + /** + * 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() { - ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); - 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()); - } + 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() { - ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); - 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()); - } + * 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() { - ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); - 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()); - } + 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 testUnlock_IllegalMonitorStateException() { - ReentrantReadWriteLock rl = new ReentrantReadWriteLock(); - try { - rl.writeLock().unlock(); - shouldThrow(); - } catch (IllegalMonitorStateException success) {} + 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_Interrupted() throws Exception { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); - Thread t = new Thread(new CheckedInterruptedRunnable() { + 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(); - lock.writeLock().unlock(); - lock.writeLock().lockInterruptibly(); - lock.writeLock().unlock(); }}); - lock.writeLock().lock(); - t.start(); - Thread.sleep(SHORT_DELAY_MS); + waitForQueuedThread(lock, t); t.interrupt(); - Thread.sleep(SHORT_DELAY_MS); - lock.writeLock().unlock(); - t.join(); + awaitTermination(t); + releaseWriteLock(lock); } /** * timed write-tryLock is interruptible */ - public void testWriteTryLock_Interrupted() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); - lock.writeLock().lock(); - Thread t = new Thread(new CheckedInterruptedRunnable() { + 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(1000,TimeUnit.MILLISECONDS); + lock.writeLock().tryLock(2 * LONG_DELAY_MS, MILLISECONDS); }}); - t.start(); + waitForQueuedThread(lock, t); t.interrupt(); - lock.writeLock().unlock(); - t.join(); + awaitTermination(t); + releaseWriteLock(lock); } /** * read-lockInterruptibly is interruptible */ - public void testReadLockInterruptibly_Interrupted() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); - lock.writeLock().lock(); - Thread t = new Thread(new CheckedInterruptedRunnable() { + 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(); }}); - t.start(); - Thread.sleep(SHORT_DELAY_MS); + waitForQueuedThread(lock, t); t.interrupt(); - Thread.sleep(SHORT_DELAY_MS); - lock.writeLock().unlock(); - t.join(); + awaitTermination(t); + releaseWriteLock(lock); } /** * timed read-tryLock is interruptible */ - public void testReadTryLock_Interrupted() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); - lock.writeLock().lock(); - Thread t = new Thread(new CheckedInterruptedRunnable() { + 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(1000,TimeUnit.MILLISECONDS); + lock.readLock().tryLock(2 * LONG_DELAY_MS, MILLISECONDS); }}); - t.start(); + waitForQueuedThread(lock, t); t.interrupt(); - t.join(); + 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() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); - lock.writeLock().lock(); - Thread t = new Thread(new Runnable() { - public void run() { - threadAssertFalse(lock.writeLock().tryLock()); - } - }); + 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()); + }}); - t.start(); - t.join(); - lock.writeLock().unlock(); + awaitTermination(t); + releaseWriteLock(lock); } /** * read-tryLock fails if locked */ - public void testReadTryLockWhenLocked() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); - lock.writeLock().lock(); - Thread t = new Thread(new Runnable() { - public void run() { - threadAssertFalse(lock.readLock().tryLock()); - } - }); + 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()); + }}); - t.start(); - t.join(); - lock.writeLock().unlock(); + awaitTermination(t); + releaseWriteLock(lock); } /** * Multiple threads can hold a read lock when not write-locked */ - public void testMultipleReadLocks() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); - lock.readLock().lock(); - Thread t = new Thread(new Runnable() { - public void run() { - threadAssertTrue(lock.readLock().tryLock()); - lock.readLock().unlock(); - } - }); + 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(); + }}); - t.start(); - t.join(); + awaitTermination(t); lock.readLock().unlock(); } /** - * A writelock succeeds after reading threads unlock + * A writelock succeeds only after a reading thread unlocks */ - public void testWriteAfterMultipleReadLocks() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); - lock.readLock().lock(); - Thread t1 = new Thread(new Runnable() { - public void run() { - lock.readLock().lock(); - lock.readLock().unlock(); - } - }); - Thread t2 = new Thread(new Runnable() { - public void run() { - lock.writeLock().lock(); - lock.writeLock().unlock(); - } - }); - - t1.start(); - t2.start(); - Thread.sleep(SHORT_DELAY_MS); + 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(); - t1.join(MEDIUM_DELAY_MS); - t2.join(MEDIUM_DELAY_MS); - assertTrue(!t1.isAlive()); - assertTrue(!t2.isAlive()); - } - - /** - * Readlocks succeed after a writing thread unlocks - */ - public void testReadAfterWriteLock() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); - lock.writeLock().lock(); - Thread t1 = new Thread(new Runnable() { - public void run() { - lock.readLock().lock(); - lock.readLock().unlock(); - } - }); - Thread t2 = new Thread(new Runnable() { - public void run() { - lock.readLock().lock(); - lock.readLock().unlock(); - } - }); - - t1.start(); - t2.start(); - Thread.sleep(SHORT_DELAY_MS); - lock.writeLock().unlock(); - t1.join(MEDIUM_DELAY_MS); - t2.join(MEDIUM_DELAY_MS); - assertTrue(!t1.isAlive()); - assertTrue(!t2.isAlive()); + assertEquals(0, lock.getReadLockCount()); + awaitTermination(t); + assertNotWriteLocked(lock); } /** - * Read trylock succeeds if write locked by current thread + * A writelock succeeds only after reading threads unlock */ - public void testReadHoldingWriteLock() { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); - lock.writeLock().lock(); - assertTrue(lock.readLock().tryLock()); + 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.writeLock().unlock(); + lock.readLock().unlock(); + assertEquals(0, lock.getReadLockCount()); + awaitTermination(t2); + assertNotWriteLocked(lock); } /** - * Read lock succeeds if write locked by current thread even if - * other threads are waiting for readlock + * A thread that tries to acquire a fair read lock (non-reentrantly) + * will block if there is a waiting writer thread */ - public void testReadHoldingWriteLock2() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); - lock.writeLock().lock(); - Thread t1 = new Thread(new Runnable() { - public void run() { - lock.readLock().lock(); - lock.readLock().unlock(); - } - }); - Thread t2 = new Thread(new Runnable() { - public void run() { - lock.readLock().lock(); - lock.readLock().unlock(); - } - }); + public void testReaderWriterReaderFairFifo() { + final PublicReentrantReadWriteLock lock = + new PublicReentrantReadWriteLock(true); + final AtomicBoolean t1GotLock = new AtomicBoolean(false); - t1.start(); - t2.start(); - lock.readLock().lock(); - lock.readLock().unlock(); - Thread.sleep(SHORT_DELAY_MS); 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(); - lock.writeLock().unlock(); - t1.join(MEDIUM_DELAY_MS); - t2.join(MEDIUM_DELAY_MS); - assertTrue(!t1.isAlive()); - assertTrue(!t2.isAlive()); + awaitTermination(t1); + awaitTermination(t2); + assertNotWriteLocked(lock); } /** - * Read lock succeeds if write locked by current thread even if - * other threads are waiting for writelock + * Readlocks succeed only after a writing thread unlocks */ - public void testReadHoldingWriteLock3() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); - lock.writeLock().lock(); - Thread t1 = new Thread(new Runnable() { - public void run() { - lock.writeLock().lock(); - lock.writeLock().unlock(); - } - }); - Thread t2 = new Thread(new Runnable() { - public void run() { - lock.writeLock().lock(); - lock.writeLock().unlock(); - } - }); + 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(); + }}); - t1.start(); - t2.start(); - lock.readLock().lock(); - lock.readLock().unlock(); - Thread.sleep(SHORT_DELAY_MS); - lock.readLock().lock(); - lock.readLock().unlock(); - lock.writeLock().unlock(); - t1.join(MEDIUM_DELAY_MS); - t2.join(MEDIUM_DELAY_MS); - assertTrue(!t1.isAlive()); - assertTrue(!t2.isAlive()); + waitForQueuedThread(lock, t1); + waitForQueuedThread(lock, t2); + releaseWriteLock(lock); + awaitTermination(t1); + awaitTermination(t2); } - /** - * Write lock succeeds if write locked by current thread even if - * other threads are waiting for writelock + * Read trylock succeeds if write locked by current thread */ - public void testWriteHoldingWriteLock4() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); - lock.writeLock().lock(); - Thread t1 = new Thread(new Runnable() { - public void run() { - lock.writeLock().lock(); - lock.writeLock().unlock(); - } - }); - Thread t2 = new Thread(new Runnable() { - public void run() { - lock.writeLock().lock(); - lock.writeLock().unlock(); - } - }); - - t1.start(); - t2.start(); - lock.writeLock().lock(); - lock.writeLock().unlock(); - Thread.sleep(SHORT_DELAY_MS); + 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(); - lock.writeLock().unlock(); - t1.join(MEDIUM_DELAY_MS); - t2.join(MEDIUM_DELAY_MS); - assertTrue(!t1.isAlive()); - assertTrue(!t2.isAlive()); } - /** - * Fair Read trylock succeeds if write locked by current thread + * Read trylock succeeds (barging) even in the presence of waiting + * readers and/or writers */ - public void testReadHoldingWriteLockFair() { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(true); - lock.writeLock().lock(); - assertTrue(lock.readLock().tryLock()); + 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(); - lock.writeLock().unlock(); + awaitTermination(t1); + awaitTermination(t2); } /** - * Fair Read lock succeeds if write locked by current thread even if + * Read lock succeeds if write locked by current thread even if * other threads are waiting for readlock */ - public void testReadHoldingWriteLockFair2() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(true); - lock.writeLock().lock(); - Thread t1 = new Thread(new Runnable() { - public void run() { - lock.readLock().lock(); - lock.readLock().unlock(); - } - }); - Thread t2 = new Thread(new Runnable() { - public void run() { - lock.readLock().lock(); - lock.readLock().unlock(); - } - }); - - t1.start(); - t2.start(); + 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.sleep(SHORT_DELAY_MS); + + 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(); - lock.writeLock().unlock(); - t1.join(MEDIUM_DELAY_MS); - t2.join(MEDIUM_DELAY_MS); - assertTrue(!t1.isAlive()); - assertTrue(!t2.isAlive()); + releaseWriteLock(lock); + awaitTermination(t1); + awaitTermination(t2); } - /** - * Fair Read lock succeeds if write locked by current thread even if + * Read lock succeeds if write locked by current thread even if * other threads are waiting for writelock */ - public void testReadHoldingWriteLockFair3() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(true); - lock.writeLock().lock(); - Thread t1 = new Thread(new Runnable() { - public void run() { - lock.writeLock().lock(); - lock.writeLock().unlock(); - } - }); - Thread t2 = new Thread(new Runnable() { - public void run() { - lock.writeLock().lock(); - lock.writeLock().unlock(); - } - }); - - t1.start(); - t2.start(); + 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.sleep(SHORT_DELAY_MS); + + 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(); - t1.join(MEDIUM_DELAY_MS); - t2.join(MEDIUM_DELAY_MS); - assertTrue(!t1.isAlive()); - assertTrue(!t2.isAlive()); + awaitTermination(t1); + awaitTermination(t2); } - /** - * Fair Write lock succeeds if write locked by current thread even if + * Write lock succeeds if write locked by current thread even if * other threads are waiting for writelock */ - public void testWriteHoldingWriteLockFair4() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(true); - lock.writeLock().lock(); - Thread t1 = new Thread(new Runnable() { - public void run() { - lock.writeLock().lock(); - lock.writeLock().unlock(); - } - }); - Thread t2 = new Thread(new Runnable() { - public void run() { - lock.writeLock().lock(); - lock.writeLock().unlock(); - } - }); - - t1.start(); - t2.start(); - Thread.sleep(SHORT_DELAY_MS); - assertTrue(lock.isWriteLockedByCurrentThread()); - assertTrue(lock.getWriteHoldCount() == 1); + 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(); - assertTrue(lock.getWriteHoldCount() == 2); 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(); - t1.join(MEDIUM_DELAY_MS); - t2.join(MEDIUM_DELAY_MS); - assertTrue(!t1.isAlive()); - assertTrue(!t2.isAlive()); + awaitTermination(t1); + awaitTermination(t2); } - /** * Read tryLock succeeds if readlocked but not writelocked */ - public void testTryLockWhenReadLocked() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); - lock.readLock().lock(); - Thread t = new Thread(new Runnable() { - public void run() { - threadAssertTrue(lock.readLock().tryLock()); - lock.readLock().unlock(); - } - }); + 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(); + }}); - t.start(); - t.join(); + awaitTermination(t); lock.readLock().unlock(); } - - /** * write tryLock fails when readlocked */ - public void testWriteTryLockWhenReadLocked() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); - lock.readLock().lock(); - Thread t = new Thread(new Runnable() { - public void run() { - threadAssertFalse(lock.writeLock().tryLock()); - } - }); - - t.start(); - t.join(); - lock.readLock().unlock(); - } - - - /** - * Fair Read tryLock succeeds if readlocked but not writelocked - */ - public void testTryLockWhenReadLockedFair() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(true); - lock.readLock().lock(); - Thread t = new Thread(new Runnable() { - public void run() { - threadAssertTrue(lock.readLock().tryLock()); - lock.readLock().unlock(); - } - }); - - t.start(); - t.join(); - lock.readLock().unlock(); - } - - - - /** - * Fair write tryLock fails when readlocked - */ - public void testWriteTryLockWhenReadLockedFair() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(true); - lock.readLock().lock(); - Thread t = new Thread(new Runnable() { - public void run() { - threadAssertFalse(lock.writeLock().tryLock()); - } - }); + 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()); + }}); - t.start(); - t.join(); + awaitTermination(t); lock.readLock().unlock(); } - - /** * write timed tryLock times out if locked */ - public void testWriteTryLock_Timeout() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); - lock.writeLock().lock(); - Thread t = new Thread(new CheckedRunnable() { + 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 { - threadAssertFalse(lock.writeLock().tryLock(1, TimeUnit.MILLISECONDS)); + long startTime = System.nanoTime(); + long timeoutMillis = 10; + assertFalse(lock.writeLock().tryLock(timeoutMillis, MILLISECONDS)); + assertTrue(millisElapsedSince(startTime) >= timeoutMillis); }}); - t.start(); - t.join(); - assertTrue(lock.writeLock().isHeldByCurrentThread()); - lock.writeLock().unlock(); + awaitTermination(t); + releaseWriteLock(lock); } /** * read timed tryLock times out if write-locked */ - public void testReadTryLock_Timeout() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); - lock.writeLock().lock(); - Thread t = new Thread(new CheckedRunnable() { + 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 { - threadAssertFalse(lock.readLock().tryLock(1, TimeUnit.MILLISECONDS)); + long startTime = System.nanoTime(); + long timeoutMillis = 10; + assertFalse(lock.readLock().tryLock(timeoutMillis, MILLISECONDS)); + assertTrue(millisElapsedSince(startTime) >= timeoutMillis); }}); - t.start(); - t.join(); + awaitTermination(t); assertTrue(lock.writeLock().isHeldByCurrentThread()); lock.writeLock().unlock(); } - /** - * write lockInterruptibly succeeds if lock free else is interruptible + * write lockInterruptibly succeeds if unlocked, else is interruptible */ - public void testWriteLockInterruptibly() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); - lock.writeLock().lockInterruptibly(); - Thread t = new Thread(new CheckedInterruptedRunnable() { + 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 ie) { + threadUnexpectedException(ie); + } + Thread t = newStartedThread(new CheckedInterruptedRunnable() { public void realRun() throws InterruptedException { lock.writeLock().lockInterruptibly(); }}); - t.start(); - Thread.sleep(SHORT_DELAY_MS); + waitForQueuedThread(lock, t); t.interrupt(); - Thread.sleep(SHORT_DELAY_MS); - t.join(); - lock.writeLock().unlock(); + assertTrue(lock.writeLock().isHeldByCurrentThread()); + awaitTermination(t); + releaseWriteLock(lock); } /** - * read lockInterruptibly succeeds if lock free else is interruptible + * read lockInterruptibly succeeds if lock free else is interruptible */ - public void testReadLockInterruptibly() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); - lock.writeLock().lockInterruptibly(); - Thread t = new Thread(new CheckedInterruptedRunnable() { + 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 ie) { + threadUnexpectedException(ie); + } + Thread t = newStartedThread(new CheckedInterruptedRunnable() { public void realRun() throws InterruptedException { lock.readLock().lockInterruptibly(); }}); - t.start(); - Thread.sleep(SHORT_DELAY_MS); + waitForQueuedThread(lock, t); t.interrupt(); - t.join(); - lock.writeLock().unlock(); + awaitTermination(t); + releaseWriteLock(lock); } /** * Calling await without holding lock throws IllegalMonitorStateException */ - public void testAwait_IllegalMonitor() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); + 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(); - try { - c.await(); - shouldThrow(); - } catch (IllegalMonitorStateException success) {} + for (AwaitMethod awaitMethod : AwaitMethod.values()) { + long startTime = System.nanoTime(); + try { + await(c, awaitMethod); + shouldThrow(); + } catch (IllegalMonitorStateException success) { + } catch (InterruptedException e) { threadUnexpectedException(e); } + assertTrue(millisElapsedSince(startTime) < LONG_DELAY_MS); + } } /** * Calling signal without holding lock throws IllegalMonitorStateException */ - public void testSignal_IllegalMonitor() { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); + 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(); @@ -777,357 +903,495 @@ public class ReentrantReadWriteLockTest } /** - * awaitNanos without a signal times out + * Calling signalAll without holding lock throws IllegalMonitorStateException */ - public void testAwaitNanos_Timeout() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); + 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(); - - lock.writeLock().lock(); - long t = c.awaitNanos(100); - assertTrue(t <= 0); - lock.writeLock().unlock(); + 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 e) { + threadUnexpectedException(e); + } + } /** - * timed await without a signal times out + * timed await without a signal times out */ - public void testAwait_Timeout() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); - final Condition c = lock.writeLock().newCondition(); - lock.writeLock().lock(); - assertFalse(c.await(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); - lock.writeLock().unlock(); + 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 e) { + threadUnexpectedException(e); + } } /** * awaitUntil without a signal times out */ - public void testAwaitUntil_Timeout() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); - final Condition c = lock.writeLock().newCondition(); - lock.writeLock().lock(); - java.util.Date d = new java.util.Date(); - assertFalse(c.awaitUntil(new java.util.Date(d.getTime() + 10))); - lock.writeLock().unlock(); + 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(); + long startTime = System.nanoTime(); + long timeoutMillis = 10; + java.util.Date d = new java.util.Date(); + assertFalse(c.awaitUntil(new java.util.Date(d.getTime() + timeoutMillis))); + assertTrue(millisElapsedSince(startTime) >= timeoutMillis); + lock.writeLock().unlock(); + } catch (InterruptedException e) { + threadUnexpectedException(e); + } } /** * await returns when signalled */ - public void testAwait() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); + 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(); - Thread t = new Thread(new CheckedRunnable() { + 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(); }}); - t.start(); - Thread.sleep(SHORT_DELAY_MS); + await(locked); lock.writeLock().lock(); + assertHasWaiters(lock, c, t); c.signal(); + assertHasNoWaiters(lock, c); + assertTrue(t.isAlive()); lock.writeLock().unlock(); - t.join(SHORT_DELAY_MS); - assertFalse(t.isAlive()); - } - - /** A helper class for uninterruptible wait tests */ - class UninterruptableThread extends Thread { - private Lock lock; - private Condition c; - - public volatile boolean canAwake = false; - public volatile boolean interrupted = false; - public volatile boolean lockStarted = false; - - public UninterruptableThread(Lock lock, Condition c) { - this.lock = lock; - this.c = c; - } - - public synchronized void run() { - lock.lock(); - lockStarted = true; - - while (!canAwake) { - c.awaitUninterruptibly(); - } - - interrupted = isInterrupted(); - lock.unlock(); - } + awaitTermination(t); } /** - * awaitUninterruptibly doesn't abort on interrupt + * awaitUninterruptibly is uninterruptible */ - public void testAwaitUninterruptibly() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); + 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(); - UninterruptableThread thread = new UninterruptableThread(lock.writeLock(), c); + final CountDownLatch pleaseInterrupt = new CountDownLatch(2); - thread.start(); + 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(); + }}); - while (!thread.lockStarted) { - Thread.sleep(100); - } + 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(); - try { - thread.interrupt(); - thread.canAwake = true; - c.signal(); - } finally { - lock.writeLock().unlock(); - } + lock.writeLock().unlock(); + t2.interrupt(); + + assertThreadStaysAlive(t1); + assertTrue(t2.isAlive()); + + lock.writeLock().lock(); + c.signalAll(); + lock.writeLock().unlock(); - thread.join(); - assertTrue(thread.interrupted); - assertFalse(thread.isAlive()); + awaitTermination(t1); + awaitTermination(t2); } /** - * await is interruptible + * await/awaitNanos/awaitUntil is interruptible */ - public void testAwait_Interrupt() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); + 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(); - Thread t = new Thread(new CheckedInterruptedRunnable() { + final CountDownLatch locked = new CountDownLatch(1); + Thread t = newStartedThread(new CheckedInterruptedRunnable() { public void realRun() throws InterruptedException { lock.writeLock().lock(); - c.await(); - lock.writeLock().unlock(); + assertWriteLockedByMoi(lock); + assertHasNoWaiters(lock, c); + locked.countDown(); + try { + await(c, awaitMethod); + } finally { + assertWriteLockedByMoi(lock); + assertHasNoWaiters(lock, c); + lock.writeLock().unlock(); + assertFalse(Thread.interrupted()); + } }}); - t.start(); - Thread.sleep(SHORT_DELAY_MS); + await(locked); + assertHasWaiters(lock, c, t); t.interrupt(); - t.join(SHORT_DELAY_MS); - assertFalse(t.isAlive()); + awaitTermination(t); + assertNotWriteLocked(lock); } /** - * awaitNanos is interruptible + * signalAll wakes up all threads */ - public void testAwaitNanos_Interrupt() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); + 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(); - Thread t = new Thread(new CheckedInterruptedRunnable() { + final CountDownLatch locked = new CountDownLatch(2); + final Lock writeLock = lock.writeLock(); + class Awaiter extends CheckedRunnable { public void realRun() throws InterruptedException { - lock.writeLock().lock(); - c.awaitNanos(SHORT_DELAY_MS * 2 * 1000000); - lock.writeLock().unlock(); - }}); + writeLock.lock(); + locked.countDown(); + await(c, awaitMethod); + writeLock.unlock(); + } + } - t.start(); - Thread.sleep(SHORT_DELAY_MS); - t.interrupt(); - t.join(SHORT_DELAY_MS); - assertFalse(t.isAlive()); + 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); } /** - * awaitUntil is interruptible + * signal wakes up waiting threads in FIFO order */ - public void testAwaitUntil_Interrupt() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); + 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(); - Thread t = new Thread(new CheckedInterruptedRunnable() { + 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 { - lock.writeLock().lock(); - java.util.Date d = new java.util.Date(); - c.awaitUntil(new java.util.Date(d.getTime() + 10000)); - lock.writeLock().unlock(); + writeLock.lock(); + locked1.countDown(); + c.await(); + writeLock.unlock(); }}); - t.start(); - Thread.sleep(SHORT_DELAY_MS); - t.interrupt(); - t.join(SHORT_DELAY_MS); - assertFalse(t.isAlive()); + 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); } /** - * signalAll wakes up all threads - */ - public void testSignalAll() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); + * 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(); - Thread t1 = new Thread(new CheckedRunnable() { + 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 = new Thread(new CheckedRunnable() { + 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(); }}); - t1.start(); - t2.start(); - Thread.sleep(SHORT_DELAY_MS); + await(locked); lock.writeLock().lock(); + assertHasWaiters(lock, c, t1, t2); c.signalAll(); + assertHasNoWaiters(lock, c); lock.writeLock().unlock(); - t1.join(SHORT_DELAY_MS); - t2.join(SHORT_DELAY_MS); - assertFalse(t1.isAlive()); - assertFalse(t2.isAlive()); + awaitTermination(t1); + awaitTermination(t2); } /** * A serialized lock deserializes as unlocked */ - public void testSerialization() throws Exception { - ReentrantReadWriteLock l = new ReentrantReadWriteLock(); - l.readLock().lock(); - l.readLock().unlock(); - - ByteArrayOutputStream bout = new ByteArrayOutputStream(10000); - ObjectOutputStream out = new ObjectOutputStream(new BufferedOutputStream(bout)); - out.writeObject(l); - out.close(); - - ByteArrayInputStream bin = new ByteArrayInputStream(bout.toByteArray()); - ObjectInputStream in = new ObjectInputStream(new BufferedInputStream(bin)); - ReentrantReadWriteLock r = (ReentrantReadWriteLock) in.readObject(); - r.readLock().lock(); - r.readLock().unlock(); + 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() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); + 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(); - Thread.sleep(SHORT_DELAY_MS); + waitForQueuedThread(lock, t1); assertTrue(lock.hasQueuedThreads()); t2.start(); - Thread.sleep(SHORT_DELAY_MS); + waitForQueuedThread(lock, t2); assertTrue(lock.hasQueuedThreads()); t1.interrupt(); - Thread.sleep(SHORT_DELAY_MS); + awaitTermination(t1); assertTrue(lock.hasQueuedThreads()); lock.writeLock().unlock(); - Thread.sleep(SHORT_DELAY_MS); + awaitTermination(t2); assertFalse(lock.hasQueuedThreads()); - t1.join(); - t2.join(); } /** * hasQueuedThread(null) throws NPE */ - public void testHasQueuedThreadNPE() { - final ReentrantReadWriteLock sync = new ReentrantReadWriteLock(); + public void testHasQueuedThreadNPE() { testHasQueuedThreadNPE(false); } + public void testHasQueuedThreadNPE_fair() { testHasQueuedThreadNPE(true); } + public void testHasQueuedThreadNPE(boolean fair) { + final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(fair); try { - sync.hasQueuedThread(null); + lock.hasQueuedThread(null); shouldThrow(); } catch (NullPointerException success) {} } /** - * hasQueuedThread reports whether a thread is queued. + * hasQueuedThread reports whether a thread is queued */ - public void testHasQueuedThread() throws InterruptedException { - final ReentrantReadWriteLock sync = new ReentrantReadWriteLock(); - Thread t1 = new Thread(new InterruptedLockRunnable(sync)); - Thread t2 = new Thread(new InterruptibleLockRunnable(sync)); - assertFalse(sync.hasQueuedThread(t1)); - assertFalse(sync.hasQueuedThread(t2)); - sync.writeLock().lock(); + 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(); - Thread.sleep(SHORT_DELAY_MS); - assertTrue(sync.hasQueuedThread(t1)); + waitForQueuedThread(lock, t1); + assertTrue(lock.hasQueuedThread(t1)); + assertFalse(lock.hasQueuedThread(t2)); t2.start(); - Thread.sleep(SHORT_DELAY_MS); - assertTrue(sync.hasQueuedThread(t1)); - assertTrue(sync.hasQueuedThread(t2)); + waitForQueuedThread(lock, t2); + assertTrue(lock.hasQueuedThread(t1)); + assertTrue(lock.hasQueuedThread(t2)); t1.interrupt(); - Thread.sleep(SHORT_DELAY_MS); - assertFalse(sync.hasQueuedThread(t1)); - assertTrue(sync.hasQueuedThread(t2)); - sync.writeLock().unlock(); - Thread.sleep(SHORT_DELAY_MS); - assertFalse(sync.hasQueuedThread(t1)); - Thread.sleep(SHORT_DELAY_MS); - assertFalse(sync.hasQueuedThread(t2)); - t1.join(); - t2.join(); + 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() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); + 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(); - Thread.sleep(SHORT_DELAY_MS); + waitForQueuedThread(lock, t1); assertEquals(1, lock.getQueueLength()); t2.start(); - Thread.sleep(SHORT_DELAY_MS); + waitForQueuedThread(lock, t2); assertEquals(2, lock.getQueueLength()); t1.interrupt(); - Thread.sleep(SHORT_DELAY_MS); + awaitTermination(t1); assertEquals(1, lock.getQueueLength()); lock.writeLock().unlock(); - Thread.sleep(SHORT_DELAY_MS); + awaitTermination(t2); assertEquals(0, lock.getQueueLength()); - t1.join(); - t2.join(); } /** * getQueuedThreads includes waiting threads */ - public void testGetQueuedThreads() throws InterruptedException { - final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(); + 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(); - Thread.sleep(SHORT_DELAY_MS); + waitForQueuedThread(lock, t1); + assertEquals(1, lock.getQueuedThreads().size()); assertTrue(lock.getQueuedThreads().contains(t1)); t2.start(); - Thread.sleep(SHORT_DELAY_MS); + waitForQueuedThread(lock, t2); + assertEquals(2, lock.getQueuedThreads().size()); assertTrue(lock.getQueuedThreads().contains(t1)); assertTrue(lock.getQueuedThreads().contains(t2)); t1.interrupt(); - Thread.sleep(SHORT_DELAY_MS); + awaitTermination(t1); assertFalse(lock.getQueuedThreads().contains(t1)); assertTrue(lock.getQueuedThreads().contains(t2)); + assertEquals(1, lock.getQueuedThreads().size()); lock.writeLock().unlock(); - Thread.sleep(SHORT_DELAY_MS); + awaitTermination(t2); assertTrue(lock.getQueuedThreads().isEmpty()); - t1.join(); - t2.join(); } /** * hasWaiters throws NPE if null */ - public void testHasWaitersNPE() { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); + 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(); @@ -1137,20 +1401,23 @@ public class ReentrantReadWriteLockTest /** * getWaitQueueLength throws NPE if null */ - public void testGetWaitQueueLengthNPE() { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); + 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() { - final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(); + 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(); @@ -1158,12 +1425,14 @@ public class ReentrantReadWriteLockTest } /** - * hasWaiters throws IAE if not owned + * hasWaiters throws IllegalArgumentException if not owned */ - public void testHasWaitersIAE() { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); + 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(); + final ReentrantReadWriteLock lock2 = new ReentrantReadWriteLock(fair); try { lock2.hasWaiters(c); shouldThrow(); @@ -1171,10 +1440,12 @@ public class ReentrantReadWriteLockTest } /** - * hasWaiters throws IMSE if not locked + * hasWaiters throws IllegalMonitorStateException if not locked */ - public void testHasWaitersIMSE() { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); + 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); @@ -1182,14 +1453,15 @@ public class ReentrantReadWriteLockTest } catch (IllegalMonitorStateException success) {} } - /** - * getWaitQueueLength throws IAE if not owned + * getWaitQueueLength throws IllegalArgumentException if not owned */ - public void testGetWaitQueueLengthIAE() { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); + 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(); + final ReentrantReadWriteLock lock2 = new ReentrantReadWriteLock(fair); try { lock2.getWaitQueueLength(c); shouldThrow(); @@ -1197,10 +1469,12 @@ public class ReentrantReadWriteLockTest } /** - * getWaitQueueLength throws IMSE if not locked + * getWaitQueueLength throws IllegalMonitorStateException if not locked */ - public void testGetWaitQueueLengthIMSE() { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); + 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); @@ -1208,14 +1482,17 @@ public class ReentrantReadWriteLockTest } catch (IllegalMonitorStateException success) {} } - /** - * getWaitingThreads throws IAE if not owned + * getWaitingThreads throws IllegalArgumentException if not owned */ - public void testGetWaitingThreadsIAE() { - final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(); + 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(); + final PublicReentrantReadWriteLock lock2 = + new PublicReentrantReadWriteLock(fair); try { lock2.getWaitingThreads(c); shouldThrow(); @@ -1223,10 +1500,13 @@ public class ReentrantReadWriteLockTest } /** - * getWaitingThreads throws IMSE if not locked + * getWaitingThreads throws IllegalMonitorStateException if not locked */ - public void testGetWaitingThreadsIMSE() { - final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(); + 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); @@ -1234,88 +1514,95 @@ public class ReentrantReadWriteLockTest } catch (IllegalMonitorStateException success) {} } - /** * hasWaiters returns true when a thread is waiting, else false */ - public void testHasWaiters() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); + 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(); - Thread t = new Thread(new CheckedRunnable() { + final CountDownLatch locked = new CountDownLatch(1); + Thread t = newStartedThread(new CheckedRunnable() { public void realRun() throws InterruptedException { lock.writeLock().lock(); - threadAssertFalse(lock.hasWaiters(c)); - threadAssertEquals(0, lock.getWaitQueueLength(c)); + assertHasNoWaiters(lock, c); + assertFalse(lock.hasWaiters(c)); + locked.countDown(); c.await(); + assertHasNoWaiters(lock, c); + assertFalse(lock.hasWaiters(c)); lock.writeLock().unlock(); }}); - t.start(); - Thread.sleep(SHORT_DELAY_MS); + await(locked); lock.writeLock().lock(); + assertHasWaiters(lock, c, t); assertTrue(lock.hasWaiters(c)); - assertEquals(1, lock.getWaitQueueLength(c)); c.signal(); - lock.writeLock().unlock(); - Thread.sleep(SHORT_DELAY_MS); - lock.writeLock().lock(); + assertHasNoWaiters(lock, c); assertFalse(lock.hasWaiters(c)); - assertEquals(0, lock.getWaitQueueLength(c)); lock.writeLock().unlock(); - t.join(SHORT_DELAY_MS); - assertFalse(t.isAlive()); + awaitTermination(t); + assertHasNoWaiters(lock, c); } /** * getWaitQueueLength returns number of waiting threads */ - public void testGetWaitQueueLength() throws InterruptedException { - final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); + 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(); - Thread t = new Thread(new CheckedRunnable() { + final CountDownLatch locked = new CountDownLatch(1); + Thread t = newStartedThread(new CheckedRunnable() { public void realRun() throws InterruptedException { lock.writeLock().lock(); - threadAssertFalse(lock.hasWaiters(c)); - threadAssertEquals(0, lock.getWaitQueueLength(c)); + assertEquals(0, lock.getWaitQueueLength(c)); + locked.countDown(); c.await(); lock.writeLock().unlock(); }}); - t.start(); - Thread.sleep(SHORT_DELAY_MS); + await(locked); lock.writeLock().lock(); - assertTrue(lock.hasWaiters(c)); + assertHasWaiters(lock, c, t); assertEquals(1, lock.getWaitQueueLength(c)); c.signal(); - lock.writeLock().unlock(); - Thread.sleep(SHORT_DELAY_MS); - lock.writeLock().lock(); - assertFalse(lock.hasWaiters(c)); + assertHasNoWaiters(lock, c); assertEquals(0, lock.getWaitQueueLength(c)); lock.writeLock().unlock(); - t.join(SHORT_DELAY_MS); - assertFalse(t.isAlive()); + awaitTermination(t); } - /** * getWaitingThreads returns only and all waiting threads */ - public void testGetWaitingThreads() throws InterruptedException { - final PublicReentrantReadWriteLock lock = new PublicReentrantReadWriteLock(); + 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(); - Thread t1 = new Thread(new CheckedRunnable() { + 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(); - threadAssertTrue(lock.getWaitingThreads(c).isEmpty()); + assertTrue(lock.getWaitingThreads(c).isEmpty()); + locked1.countDown(); c.await(); lock.writeLock().unlock(); }}); - Thread t2 = new Thread(new CheckedRunnable() { + Thread t2 = new Thread(new CheckedRunnable() { public void realRun() throws InterruptedException { lock.writeLock().lock(); - threadAssertFalse(lock.getWaitingThreads(c).isEmpty()); + assertFalse(lock.getWaitingThreads(c).isEmpty()); + locked2.countDown(); c.await(); lock.writeLock().unlock(); }}); @@ -1323,70 +1610,71 @@ public class ReentrantReadWriteLockTest lock.writeLock().lock(); assertTrue(lock.getWaitingThreads(c).isEmpty()); lock.writeLock().unlock(); + t1.start(); - Thread.sleep(SHORT_DELAY_MS); + await(locked1); t2.start(); - Thread.sleep(SHORT_DELAY_MS); + 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(); - Thread.sleep(SHORT_DELAY_MS); - lock.writeLock().lock(); - assertFalse(lock.hasWaiters(c)); - assertTrue(lock.getWaitingThreads(c).isEmpty()); - lock.writeLock().unlock(); - t1.join(SHORT_DELAY_MS); - t2.join(SHORT_DELAY_MS); - assertFalse(t1.isAlive()); - assertFalse(t2.isAlive()); + + awaitTermination(t1); + awaitTermination(t2); + + assertHasNoWaiters(lock, c); } /** * toString indicates current lock state */ - public void testToString() { - ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); - String us = lock.toString(); - assertTrue(us.indexOf("Write locks = 0") >= 0); - assertTrue(us.indexOf("Read locks = 0") >= 0); - lock.writeLock().lock(); - String ws = lock.toString(); - assertTrue(ws.indexOf("Write locks = 1") >= 0); - assertTrue(ws.indexOf("Read locks = 0") >= 0); + 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(); - String rs = lock.toString(); - assertTrue(rs.indexOf("Write locks = 0") >= 0); - assertTrue(rs.indexOf("Read locks = 2") >= 0); + assertTrue(lock.toString().contains("Write locks = 0")); + assertTrue(lock.toString().contains("Read locks = 2")); } /** * readLock.toString indicates current lock state */ - public void testReadLockToString() { - ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); - String us = lock.readLock().toString(); - assertTrue(us.indexOf("Read locks = 0") >= 0); + 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(); - String rs = lock.readLock().toString(); - assertTrue(rs.indexOf("Read locks = 2") >= 0); + assertTrue(lock.readLock().toString().contains("Read locks = 2")); } /** * writeLock.toString indicates current lock state */ - public void testWriteLockToString() { - ReentrantReadWriteLock lock = new ReentrantReadWriteLock(); - String us = lock.writeLock().toString(); - assertTrue(us.indexOf("Unlocked") >= 0); + 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(); - String ls = lock.writeLock().toString(); - assertTrue(ls.indexOf("Locked") >= 0); + assertTrue(lock.writeLock().toString().contains("Locked")); + lock.writeLock().unlock(); + assertTrue(lock.writeLock().toString().contains("Unlocked")); } }