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root/jsr166/jsr166/src/test/tck/StampedLockTest.java

Comparing jsr166/src/test/tck/StampedLockTest.java (file contents):
Revision 1.12 by jsr166, Fri Feb 27 21:54:13 2015 UTC vs.
Revision 1.47 by dl, Tue Jan 26 13:33:06 2021 UTC

#	Line 5 | Line 5
5		* http://creativecommons.org/publicdomain/zero/1.0/
6		*/
7
8	+	import static java.util.concurrent.TimeUnit.DAYS;
9		import static java.util.concurrent.TimeUnit.MILLISECONDS;
10
11	+	import static java.util.concurrent.locks.StampedLock.isLockStamp;
12	+	import static java.util.concurrent.locks.StampedLock.isOptimisticReadStamp;
13	+	import static java.util.concurrent.locks.StampedLock.isReadLockStamp;
14	+	import static java.util.concurrent.locks.StampedLock.isWriteLockStamp;
15	+
16	+	import java.util.ArrayList;
17	+	import java.util.List;
18	+	import java.util.concurrent.Callable;
19	+	import java.util.concurrent.CompletableFuture;
20		import java.util.concurrent.CountDownLatch;
21	+	import java.util.concurrent.Future;
22	+	import java.util.concurrent.ThreadLocalRandom;
23	+	import java.util.concurrent.TimeUnit;
24	+	import java.util.concurrent.atomic.AtomicBoolean;
25		import java.util.concurrent.locks.Lock;
26		import java.util.concurrent.locks.StampedLock;
27	+	import java.util.function.BiConsumer;
28	+	import java.util.function.Consumer;
29	+	import java.util.function.Function;
30
31		import junit.framework.Test;
32		import junit.framework.TestSuite;
33
34		public class StampedLockTest extends JSR166TestCase {
35		public static void main(String[] args) {
36	<	junit.textui.TestRunner.run(suite());
36	>	main(suite(), args);
37		}
38		public static Test suite() {
39		return new TestSuite(StampedLockTest.class);
40		}
41
42		/**
26	–	* A runnable calling writeLockInterruptibly
27	–	*/
28	–	class InterruptibleLockRunnable extends CheckedRunnable {
29	–	final StampedLock lock;
30	–	InterruptibleLockRunnable(StampedLock l) { lock = l; }
31	–	public void realRun() throws InterruptedException {
32	–	lock.writeLockInterruptibly();
33	–	}
34	–	}
35	–
36	–	/**
37	–	* A runnable calling writeLockInterruptibly that expects to be
38	–	* interrupted
39	–	*/
40	–	class InterruptedLockRunnable extends CheckedInterruptedRunnable {
41	–	final StampedLock lock;
42	–	InterruptedLockRunnable(StampedLock l) { lock = l; }
43	–	public void realRun() throws InterruptedException {
44	–	lock.writeLockInterruptibly();
45	–	}
46	–	}
47	–
48	–	/**
43		* Releases write lock, checking isWriteLocked before and after
44		*/
45	<	void releaseWriteLock(StampedLock lock, long s) {
45	>	void releaseWriteLock(StampedLock lock, long stamp) {
46		assertTrue(lock.isWriteLocked());
47	<	lock.unlockWrite(s);
47	>	assertValid(lock, stamp);
48	>	lock.unlockWrite(stamp);
49		assertFalse(lock.isWriteLocked());
50	+	assertFalse(lock.validate(stamp));
51		}
52
53		/**
54	<	* Constructed StampedLock is in unlocked state
54	>	* Releases read lock, checking isReadLocked before and after
55		*/
56	<	public void testConstructor() {
57	<	StampedLock lock;
58	<	lock = new StampedLock();
59	<	assertFalse(lock.isWriteLocked());
56	>	void releaseReadLock(StampedLock lock, long stamp) {
57	>	assertTrue(lock.isReadLocked());
58	>	assertValid(lock, stamp);
59	>	lock.unlockRead(stamp);
60		assertFalse(lock.isReadLocked());
61	<	assertEquals(lock.getReadLockCount(), 0);
61	>	assertTrue(lock.validate(stamp));
62		}
63
64	<	/**
65	<	* write-locking and read-locking an unlocked lock succeed
66	<	*/
71	<	public void testLock() {
72	<	StampedLock lock = new StampedLock();
73	<	assertFalse(lock.isWriteLocked());
74	<	assertFalse(lock.isReadLocked());
75	<	assertEquals(lock.getReadLockCount(), 0);
76	<	long s = lock.writeLock();
77	<	assertTrue(lock.isWriteLocked());
78	<	assertFalse(lock.isReadLocked());
79	<	assertEquals(lock.getReadLockCount(), 0);
80	<	lock.unlockWrite(s);
81	<	assertFalse(lock.isWriteLocked());
82	<	assertFalse(lock.isReadLocked());
83	<	assertEquals(lock.getReadLockCount(), 0);
84	<	long rs = lock.readLock();
85	<	assertFalse(lock.isWriteLocked());
86	<	assertTrue(lock.isReadLocked());
87	<	assertEquals(lock.getReadLockCount(), 1);
88	<	lock.unlockRead(rs);
89	<	assertFalse(lock.isWriteLocked());
90	<	assertFalse(lock.isReadLocked());
91	<	assertEquals(lock.getReadLockCount(), 0);
64	>	long assertNonZero(long v) {
65	>	assertTrue(v != 0L);
66	>	return v;
67		}
68
69	<	/**
70	<	* unlock releases either a read or write lock
71	<	*/
72	<	public void testUnlock() {
98	<	StampedLock lock = new StampedLock();
99	<	assertFalse(lock.isWriteLocked());
100	<	assertFalse(lock.isReadLocked());
101	<	assertEquals(lock.getReadLockCount(), 0);
102	<	long s = lock.writeLock();
103	<	assertTrue(lock.isWriteLocked());
104	<	assertFalse(lock.isReadLocked());
105	<	assertEquals(lock.getReadLockCount(), 0);
106	<	lock.unlock(s);
107	<	assertFalse(lock.isWriteLocked());
108	<	assertFalse(lock.isReadLocked());
109	<	assertEquals(lock.getReadLockCount(), 0);
110	<	long rs = lock.readLock();
111	<	assertFalse(lock.isWriteLocked());
112	<	assertTrue(lock.isReadLocked());
113	<	assertEquals(lock.getReadLockCount(), 1);
114	<	lock.unlock(rs);
115	<	assertFalse(lock.isWriteLocked());
116	<	assertFalse(lock.isReadLocked());
117	<	assertEquals(lock.getReadLockCount(), 0);
69	>	long assertValid(StampedLock lock, long stamp) {
70	>	assertTrue(stamp != 0L);
71	>	assertTrue(lock.validate(stamp));
72	>	return stamp;
73		}
74
75	<	/**
121	<	* tryUnlockRead/Write succeeds if locked in associated mode else
122	<	* returns false
123	<	*/
124	<	public void testTryUnlock() {
125	<	StampedLock lock = new StampedLock();
126	<	assertFalse(lock.isWriteLocked());
127	<	assertFalse(lock.isReadLocked());
128	<	assertEquals(lock.getReadLockCount(), 0);
129	<	long s = lock.writeLock();
130	<	assertTrue(lock.isWriteLocked());
75	>	void assertUnlocked(StampedLock lock) {
76		assertFalse(lock.isReadLocked());
132	–	assertEquals(lock.getReadLockCount(), 0);
133	–	assertFalse(lock.tryUnlockRead());
134	–	assertTrue(lock.tryUnlockWrite());
135	–	assertFalse(lock.tryUnlockWrite());
136	–	assertFalse(lock.tryUnlockRead());
77		assertFalse(lock.isWriteLocked());
78	<	assertFalse(lock.isReadLocked());
79	<	assertEquals(lock.getReadLockCount(), 0);
140	<	long rs = lock.readLock();
141	<	assertFalse(lock.isWriteLocked());
142	<	assertTrue(lock.isReadLocked());
143	<	assertEquals(lock.getReadLockCount(), 1);
144	<	assertFalse(lock.tryUnlockWrite());
145	<	assertTrue(lock.tryUnlockRead());
146	<	assertFalse(lock.tryUnlockRead());
147	<	assertFalse(lock.tryUnlockWrite());
148	<	assertFalse(lock.isWriteLocked());
149	<	assertFalse(lock.isReadLocked());
150	<	assertEquals(lock.getReadLockCount(), 0);
78	>	assertEquals(0, lock.getReadLockCount());
79	>	assertValid(lock, lock.tryOptimisticRead());
80		}
81
82	<	/**
83	<	* write-unlocking an unlocked lock throws IllegalMonitorStateException
84	<	*/
85	<	public void testWriteUnlock_IMSE() {
86	<	StampedLock lock = new StampedLock();
87	<	try {
88	<	lock.unlockWrite(0L);
89	<	shouldThrow();
90	<	} catch (IllegalMonitorStateException success) {}
82	>	List<Action> lockLockers(Lock lock) {
83	>	return List.of(
84	>	() -> lock.lock(),
85	>	() -> lock.lockInterruptibly(),
86	>	() -> lock.tryLock(),
87	>	() -> lock.tryLock(Long.MIN_VALUE, DAYS),
88	>	() -> lock.tryLock(0L, DAYS),
89	>	() -> lock.tryLock(Long.MAX_VALUE, DAYS));
90	>	}
91	>
92	>	List<Function<StampedLock, Long>> readLockers() {
93	>	return List.of(
94	>	sl -> sl.readLock(),
95	>	sl -> sl.tryReadLock(),
96	>	sl -> readLockInterruptiblyUninterrupted(sl),
97	>	sl -> tryReadLockUninterrupted(sl, Long.MIN_VALUE, DAYS),
98	>	sl -> tryReadLockUninterrupted(sl, 0L, DAYS),
99	>	sl -> sl.tryConvertToReadLock(sl.tryOptimisticRead()));
100	>	}
101	>
102	>	List<BiConsumer<StampedLock, Long>> readUnlockers() {
103	>	return List.of(
104	>	(sl, stamp) -> sl.unlockRead(stamp),
105	>	(sl, stamp) -> assertTrue(sl.tryUnlockRead()),
106	>	(sl, stamp) -> sl.asReadLock().unlock(),
107	>	(sl, stamp) -> sl.unlock(stamp),
108	>	(sl, stamp) -> assertValid(sl, sl.tryConvertToOptimisticRead(stamp)));
109	>	}
110	>
111	>	List<Function<StampedLock, Long>> writeLockers() {
112	>	return List.of(
113	>	sl -> sl.writeLock(),
114	>	sl -> sl.tryWriteLock(),
115	>	sl -> writeLockInterruptiblyUninterrupted(sl),
116	>	sl -> tryWriteLockUninterrupted(sl, Long.MIN_VALUE, DAYS),
117	>	sl -> tryWriteLockUninterrupted(sl, 0L, DAYS),
118	>	sl -> sl.tryConvertToWriteLock(sl.tryOptimisticRead()));
119	>	}
120	>
121	>	List<BiConsumer<StampedLock, Long>> writeUnlockers() {
122	>	return List.of(
123	>	(sl, stamp) -> sl.unlockWrite(stamp),
124	>	(sl, stamp) -> assertTrue(sl.tryUnlockWrite()),
125	>	(sl, stamp) -> sl.asWriteLock().unlock(),
126	>	(sl, stamp) -> sl.unlock(stamp),
127	>	(sl, stamp) -> assertValid(sl, sl.tryConvertToOptimisticRead(stamp)));
128		}
129
130		/**
131	<	* write-unlocking an unlocked lock throws IllegalMonitorStateException
131	>	* Constructed StampedLock is in unlocked state
132		*/
133	<	public void testWriteUnlock_IMSE2() {
134	<	StampedLock lock = new StampedLock();
169	<	try {
170	<	long s = lock.writeLock();
171	<	lock.unlockWrite(s);
172	<	lock.unlockWrite(s);
173	<	shouldThrow();
174	<	} catch (IllegalMonitorStateException success) {}
133	>	public void testConstructor() {
134	>	assertUnlocked(new StampedLock());
135		}
136
137		/**
138	<	* write-unlocking after readlock throws IllegalMonitorStateException
138	>	* write-locking, then unlocking, an unlocked lock succeed
139		*/
140	<	public void testWriteUnlock_IMSE3() {
140	>	public void testWriteLock_lockUnlock() {
141		StampedLock lock = new StampedLock();
142	<	try {
143	<	long s = lock.readLock();
144	<	lock.unlockWrite(s);
145	<	shouldThrow();
146	<	} catch (IllegalMonitorStateException success) {}
142	>
143	>	for (Function<StampedLock, Long> writeLocker : writeLockers())
144	>	for (BiConsumer<StampedLock, Long> writeUnlocker : writeUnlockers()) {
145	>	assertFalse(lock.isWriteLocked());
146	>	assertFalse(lock.isReadLocked());
147	>	assertEquals(0, lock.getReadLockCount());
148	>
149	>	long s = writeLocker.apply(lock);
150	>	assertValid(lock, s);
151	>	assertTrue(lock.isWriteLocked());
152	>	assertFalse(lock.isReadLocked());
153	>	assertEquals(0, lock.getReadLockCount());
154	>	writeUnlocker.accept(lock, s);
155	>	assertUnlocked(lock);
156	>	}
157		}
158
159		/**
160	<	* read-unlocking an unlocked lock throws IllegalMonitorStateException
160	>	* read-locking, then unlocking, an unlocked lock succeed
161		*/
162	<	public void testReadUnlock_IMSE() {
162	>	public void testReadLock_lockUnlock() {
163		StampedLock lock = new StampedLock();
164	<	try {
165	<	long s = lock.readLock();
166	<	lock.unlockRead(s);
167	<	lock.unlockRead(s);
168	<	shouldThrow();
169	<	} catch (IllegalMonitorStateException success) {}
164	>
165	>	for (Function<StampedLock, Long> readLocker : readLockers())
166	>	for (BiConsumer<StampedLock, Long> readUnlocker : readUnlockers()) {
167	>	long s = 42;
168	>	for (int i = 0; i < 2; i++) {
169	>	s = assertValid(lock, readLocker.apply(lock));
170	>	assertFalse(lock.isWriteLocked());
171	>	assertTrue(lock.isReadLocked());
172	>	assertEquals(i + 1, lock.getReadLockCount());
173	>	}
174	>	for (int i = 0; i < 2; i++) {
175	>	assertFalse(lock.isWriteLocked());
176	>	assertTrue(lock.isReadLocked());
177	>	assertEquals(2 - i, lock.getReadLockCount());
178	>	readUnlocker.accept(lock, s);
179	>	}
180	>	assertUnlocked(lock);
181	>	}
182		}
183
184		/**
185	<	* read-unlocking an unlocked lock throws IllegalMonitorStateException
185	>	* tryUnlockWrite fails if not write locked
186		*/
187	<	public void testReadUnlock_IMSE2() {
187	>	public void testTryUnlockWrite_failure() {
188		StampedLock lock = new StampedLock();
189	<	try {
190	<	lock.unlockRead(0L);
191	<	shouldThrow();
192	<	} catch (IllegalMonitorStateException success) {}
189	>	assertFalse(lock.tryUnlockWrite());
190	>
191	>	for (Function<StampedLock, Long> readLocker : readLockers())
192	>	for (BiConsumer<StampedLock, Long> readUnlocker : readUnlockers()) {
193	>	long s = assertValid(lock, readLocker.apply(lock));
194	>	assertFalse(lock.tryUnlockWrite());
195	>	assertTrue(lock.isReadLocked());
196	>	readUnlocker.accept(lock, s);
197	>	assertUnlocked(lock);
198	>	}
199		}
200
201		/**
202	<	* read-unlocking after writeLock throws IllegalMonitorStateException
202	>	* tryUnlockRead fails if not read locked
203		*/
204	<	public void testReadUnlock_IMSE3() {
204	>	public void testTryUnlockRead_failure() {
205		StampedLock lock = new StampedLock();
206	<	try {
207	<	long s = lock.writeLock();
208	<	lock.unlockRead(s);
209	<	shouldThrow();
210	<	} catch (IllegalMonitorStateException success) {}
206	>	assertFalse(lock.tryUnlockRead());
207	>
208	>	for (Function<StampedLock, Long> writeLocker : writeLockers())
209	>	for (BiConsumer<StampedLock, Long> writeUnlocker : writeUnlockers()) {
210	>	long s = writeLocker.apply(lock);
211	>	assertFalse(lock.tryUnlockRead());
212	>	assertTrue(lock.isWriteLocked());
213	>	writeUnlocker.accept(lock, s);
214	>	assertUnlocked(lock);
215	>	}
216		}
217
218		/**
219	<	* validate(0) fails
219	>	* validate(0L) fails
220		*/
221		public void testValidate0() {
222		StampedLock lock = new StampedLock();
#	Line 231 | Line 224 | public class StampedLockTest extends JSR
224		}
225
226		/**
227	<	* A stamp obtained from a successful lock operation validates
227	>	* A stamp obtained from a successful lock operation validates while the lock is held
228		*/
229		public void testValidate() throws InterruptedException {
230		StampedLock lock = new StampedLock();
231	<	long s = lock.writeLock();
232	<	assertTrue(lock.validate(s));
233	<	lock.unlockWrite(s);
234	<	s = lock.readLock();
235	<	assertTrue(lock.validate(s));
236	<	lock.unlockRead(s);
237	<	assertTrue((s = lock.tryWriteLock()) != 0L);
238	<	assertTrue(lock.validate(s));
239	<	lock.unlockWrite(s);
240	<	assertTrue((s = lock.tryReadLock()) != 0L);
241	<	assertTrue(lock.validate(s));
242	<	lock.unlockRead(s);
243	<	assertTrue((s = lock.tryWriteLock(100L, MILLISECONDS)) != 0L);
244	<	assertTrue(lock.validate(s));
252	<	lock.unlockWrite(s);
253	<	assertTrue((s = lock.tryReadLock(100L, MILLISECONDS)) != 0L);
254	<	assertTrue(lock.validate(s));
255	<	lock.unlockRead(s);
256	<	assertTrue((s = lock.tryOptimisticRead()) != 0L);
231	>
232	>	for (Function<StampedLock, Long> readLocker : readLockers())
233	>	for (BiConsumer<StampedLock, Long> readUnlocker : readUnlockers()) {
234	>	long s = assertNonZero(readLocker.apply(lock));
235	>	assertTrue(lock.validate(s));
236	>	readUnlocker.accept(lock, s);
237	>	}
238	>
239	>	for (Function<StampedLock, Long> writeLocker : writeLockers())
240	>	for (BiConsumer<StampedLock, Long> writeUnlocker : writeUnlockers()) {
241	>	long s = assertNonZero(writeLocker.apply(lock));
242	>	assertTrue(lock.validate(s));
243	>	writeUnlocker.accept(lock, s);
244	>	}
245		}
246
247		/**
#	Line 261 | Line 249 | public class StampedLockTest extends JSR
249		*/
250		public void testValidate2() throws InterruptedException {
251		StampedLock lock = new StampedLock();
252	<	long s;
265	<	assertTrue((s = lock.writeLock()) != 0L);
252	>	long s = assertNonZero(lock.writeLock());
253		assertTrue(lock.validate(s));
254		assertFalse(lock.validate(lock.tryWriteLock()));
255	<	assertFalse(lock.validate(lock.tryWriteLock(10L, MILLISECONDS)));
255	>	assertFalse(lock.validate(lock.tryWriteLock(randomExpiredTimeout(),
256	>	randomTimeUnit())));
257		assertFalse(lock.validate(lock.tryReadLock()));
258	<	assertFalse(lock.validate(lock.tryReadLock(10L, MILLISECONDS)));
258	>	assertFalse(lock.validate(lock.tryWriteLock(randomExpiredTimeout(),
259	>	randomTimeUnit())));
260		assertFalse(lock.validate(lock.tryOptimisticRead()));
261		lock.unlockWrite(s);
262		}
263
264	+	void assertThrowInterruptedExceptionWhenPreInterrupted(Action[] actions) {
265	+	for (Action action : actions) {
266	+	Thread.currentThread().interrupt();
267	+	try {
268	+	action.run();
269	+	shouldThrow();
270	+	}
271	+	catch (InterruptedException success) {}
272	+	catch (Throwable fail) { threadUnexpectedException(fail); }
273	+	assertFalse(Thread.interrupted());
274	+	}
275	+	}
276	+
277		/**
278	<	* writeLockInterruptibly is interruptible
278	>	* interruptible operations throw InterruptedException when pre-interrupted
279		*/
280	<	public void testWriteLockInterruptibly_Interruptible()
279	<	throws InterruptedException {
280	<	final CountDownLatch running = new CountDownLatch(1);
280	>	public void testInterruptibleOperationsThrowInterruptedExceptionWhenPreInterrupted() {
281		final StampedLock lock = new StampedLock();
282	–	long s = lock.writeLock();
283	–	Thread t = newStartedThread(new CheckedInterruptedRunnable() {
284	–	public void realRun() throws InterruptedException {
285	–	running.countDown();
286	–	lock.writeLockInterruptibly();
287	–	}});
282
283	<	running.await();
284	<	waitForThreadToEnterWaitState(t, 100);
285	<	t.interrupt();
286	<	awaitTermination(t);
287	<	releaseWriteLock(lock, s);
283	>	Action[] interruptibleLockActions = {
284	>	() -> lock.writeLockInterruptibly(),
285	>	() -> lock.tryWriteLock(Long.MIN_VALUE, DAYS),
286	>	() -> lock.tryWriteLock(Long.MAX_VALUE, DAYS),
287	>	() -> lock.readLockInterruptibly(),
288	>	() -> lock.tryReadLock(Long.MIN_VALUE, DAYS),
289	>	() -> lock.tryReadLock(Long.MAX_VALUE, DAYS),
290	>	() -> lock.asWriteLock().lockInterruptibly(),
291	>	() -> lock.asWriteLock().tryLock(0L, DAYS),
292	>	() -> lock.asWriteLock().tryLock(Long.MAX_VALUE, DAYS),
293	>	() -> lock.asReadLock().lockInterruptibly(),
294	>	() -> lock.asReadLock().tryLock(0L, DAYS),
295	>	() -> lock.asReadLock().tryLock(Long.MAX_VALUE, DAYS),
296	>	};
297	>	shuffle(interruptibleLockActions);
298	>
299	>	assertThrowInterruptedExceptionWhenPreInterrupted(interruptibleLockActions);
300	>	{
301	>	long s = lock.writeLock();
302	>	assertThrowInterruptedExceptionWhenPreInterrupted(interruptibleLockActions);
303	>	lock.unlockWrite(s);
304	>	}
305	>	{
306	>	long s = lock.readLock();
307	>	assertThrowInterruptedExceptionWhenPreInterrupted(interruptibleLockActions);
308	>	lock.unlockRead(s);
309	>	}
310	>	}
311	>
312	>	void assertThrowInterruptedExceptionWhenInterrupted(Action[] actions) {
313	>	int n = actions.length;
314	>	Future<?>[] futures = new Future<?>[n];
315	>	CountDownLatch threadsStarted = new CountDownLatch(n);
316	>	CountDownLatch done = new CountDownLatch(n);
317	>
318	>	for (int i = 0; i < n; i++) {
319	>	Action action = actions[i];
320	>	futures[i] = cachedThreadPool.submit(new CheckedRunnable() {
321	>	public void realRun() throws Throwable {
322	>	threadsStarted.countDown();
323	>	try {
324	>	action.run();
325	>	shouldThrow();
326	>	}
327	>	catch (InterruptedException success) {}
328	>	catch (Throwable fail) { threadUnexpectedException(fail); }
329	>	assertFalse(Thread.interrupted());
330	>	done.countDown();
331	>	}});
332	>	}
333	>
334	>	await(threadsStarted);
335	>	assertEquals(n, done.getCount());
336	>	for (Future<?> future : futures) // Interrupt all the tasks
337	>	future.cancel(true);
338	>	await(done);
339		}
340
341		/**
342	<	* timed tryWriteLock is interruptible
342	>	* interruptible operations throw InterruptedException when write locked and interrupted
343		*/
344	<	public void testWriteTryLock_Interruptible() throws InterruptedException {
300	<	final CountDownLatch running = new CountDownLatch(1);
344	>	public void testInterruptibleOperationsThrowInterruptedExceptionWriteLockedInterrupted() {
345		final StampedLock lock = new StampedLock();
346	<	long s = lock.writeLock();
303	<	Thread t = newStartedThread(new CheckedInterruptedRunnable() {
304	<	public void realRun() throws InterruptedException {
305	<	running.countDown();
306	<	lock.tryWriteLock(2 * LONG_DELAY_MS, MILLISECONDS);
307	<	}});
346	>	long stamp = lock.writeLock();
347
348	<	running.await();
349	<	waitForThreadToEnterWaitState(t, 100);
350	<	t.interrupt();
351	<	awaitTermination(t);
352	<	releaseWriteLock(lock, s);
348	>	Action[] interruptibleLockBlockingActions = {
349	>	() -> lock.writeLockInterruptibly(),
350	>	() -> lock.tryWriteLock(Long.MAX_VALUE, DAYS),
351	>	() -> lock.readLockInterruptibly(),
352	>	() -> lock.tryReadLock(Long.MAX_VALUE, DAYS),
353	>	() -> lock.asWriteLock().lockInterruptibly(),
354	>	() -> lock.asWriteLock().tryLock(Long.MAX_VALUE, DAYS),
355	>	() -> lock.asReadLock().lockInterruptibly(),
356	>	() -> lock.asReadLock().tryLock(Long.MAX_VALUE, DAYS),
357	>	};
358	>	shuffle(interruptibleLockBlockingActions);
359	>
360	>	assertThrowInterruptedExceptionWhenInterrupted(interruptibleLockBlockingActions);
361	>
362	>	releaseWriteLock(lock, stamp);
363		}
364
365		/**
366	<	* readLockInterruptibly is interruptible
366	>	* interruptible operations throw InterruptedException when read locked and interrupted
367		*/
368	<	public void testReadLockInterruptibly_Interruptible()
320	<	throws InterruptedException {
321	<	final CountDownLatch running = new CountDownLatch(1);
368	>	public void testInterruptibleOperationsThrowInterruptedExceptionReadLockedInterrupted() {
369		final StampedLock lock = new StampedLock();
370	<	long s = lock.writeLock();
324	<	Thread t = newStartedThread(new CheckedInterruptedRunnable() {
325	<	public void realRun() throws InterruptedException {
326	<	running.countDown();
327	<	lock.readLockInterruptibly();
328	<	}});
370	>	long stamp = lock.readLock();
371
372	<	running.await();
373	<	waitForThreadToEnterWaitState(t, 100);
374	<	t.interrupt();
375	<	awaitTermination(t);
376	<	releaseWriteLock(lock, s);
372	>	Action[] interruptibleLockBlockingActions = {
373	>	() -> lock.writeLockInterruptibly(),
374	>	() -> lock.tryWriteLock(Long.MAX_VALUE, DAYS),
375	>	() -> lock.asWriteLock().lockInterruptibly(),
376	>	() -> lock.asWriteLock().tryLock(Long.MAX_VALUE, DAYS),
377	>	};
378	>	shuffle(interruptibleLockBlockingActions);
379	>
380	>	assertThrowInterruptedExceptionWhenInterrupted(interruptibleLockBlockingActions);
381	>
382	>	releaseReadLock(lock, stamp);
383		}
384
385		/**
386	<	* timed tryReadLock is interruptible
386	>	* Non-interruptible operations ignore and preserve interrupt status
387		*/
388	<	public void testReadTryLock_Interruptible() throws InterruptedException {
341	<	final CountDownLatch running = new CountDownLatch(1);
388	>	public void testNonInterruptibleOperationsIgnoreInterrupts() {
389		final StampedLock lock = new StampedLock();
390	<	long s = lock.writeLock();
344	<	Thread t = newStartedThread(new CheckedInterruptedRunnable() {
345	<	public void realRun() throws InterruptedException {
346	<	running.countDown();
347	<	lock.tryReadLock(2 * LONG_DELAY_MS, MILLISECONDS);
348	<	}});
390	>	Thread.currentThread().interrupt();
391
392	<	running.await();
393	<	waitForThreadToEnterWaitState(t, 100);
394	<	t.interrupt();
395	<	awaitTermination(t);
396	<	releaseWriteLock(lock, s);
392	>	for (BiConsumer<StampedLock, Long> readUnlocker : readUnlockers()) {
393	>	long s = assertValid(lock, lock.readLock());
394	>	readUnlocker.accept(lock, s);
395	>	s = assertValid(lock, lock.tryReadLock());
396	>	readUnlocker.accept(lock, s);
397	>	}
398	>
399	>	lock.asReadLock().lock();
400	>	lock.asReadLock().unlock();
401	>
402	>	for (BiConsumer<StampedLock, Long> writeUnlocker : writeUnlockers()) {
403	>	long s = assertValid(lock, lock.writeLock());
404	>	writeUnlocker.accept(lock, s);
405	>	s = assertValid(lock, lock.tryWriteLock());
406	>	writeUnlocker.accept(lock, s);
407	>	}
408	>
409	>	lock.asWriteLock().lock();
410	>	lock.asWriteLock().unlock();
411	>
412	>	assertTrue(Thread.interrupted());
413		}
414
415		/**
416		* tryWriteLock on an unlocked lock succeeds
417		*/
418	<	public void testWriteTryLock() {
418	>	public void testTryWriteLock() {
419		final StampedLock lock = new StampedLock();
420		long s = lock.tryWriteLock();
421		assertTrue(s != 0L);
422		assertTrue(lock.isWriteLocked());
423	<	long s2 = lock.tryWriteLock();
366	<	assertEquals(s2, 0L);
423	>	assertEquals(0L, lock.tryWriteLock());
424		releaseWriteLock(lock, s);
425		}
426
427		/**
428		* tryWriteLock fails if locked
429		*/
430	<	public void testWriteTryLockWhenLocked() {
430	>	public void testTryWriteLockWhenLocked() {
431		final StampedLock lock = new StampedLock();
432		long s = lock.writeLock();
433		Thread t = newStartedThread(new CheckedRunnable() {
434		public void realRun() {
435	<	long ws = lock.tryWriteLock();
379	<	assertTrue(ws == 0L);
435	>	assertEquals(0L, lock.tryWriteLock());
436		}});
437
438	+	assertEquals(0L, lock.tryWriteLock());
439		awaitTermination(t);
440		releaseWriteLock(lock, s);
441		}
#	Line 386 | Line 443 | public class StampedLockTest extends JSR
443		/**
444		* tryReadLock fails if write-locked
445		*/
446	<	public void testReadTryLockWhenLocked() {
446	>	public void testTryReadLockWhenLocked() {
447		final StampedLock lock = new StampedLock();
448		long s = lock.writeLock();
449		Thread t = newStartedThread(new CheckedRunnable() {
450		public void realRun() {
451	<	long rs = lock.tryReadLock();
395	<	assertEquals(rs, 0L);
451	>	assertEquals(0L, lock.tryReadLock());
452		}});
453
454	+	assertEquals(0L, lock.tryReadLock());
455		awaitTermination(t);
456		releaseWriteLock(lock, s);
457		}
#	Line 408 | Line 465 | public class StampedLockTest extends JSR
465		Thread t = newStartedThread(new CheckedRunnable() {
466		public void realRun() throws InterruptedException {
467		long s2 = lock.tryReadLock();
468	<	assertTrue(s2 != 0L);
468	>	assertValid(lock, s2);
469		lock.unlockRead(s2);
470		long s3 = lock.tryReadLock(LONG_DELAY_MS, MILLISECONDS);
471	<	assertTrue(s3 != 0L);
471	>	assertValid(lock, s3);
472		lock.unlockRead(s3);
473		long s4 = lock.readLock();
474	+	assertValid(lock, s4);
475		lock.unlockRead(s4);
476	+	lock.asReadLock().lock();
477	+	lock.asReadLock().unlock();
478	+	lock.asReadLock().lockInterruptibly();
479	+	lock.asReadLock().unlock();
480	+	lock.asReadLock().tryLock(Long.MIN_VALUE, DAYS);
481	+	lock.asReadLock().unlock();
482		}});
483
484		awaitTermination(t);
#	Line 422 | Line 486 | public class StampedLockTest extends JSR
486		}
487
488		/**
489	<	* A writelock succeeds only after a reading thread unlocks
489	>	* writeLock() succeeds only after a reading thread unlocks
490		*/
491		public void testWriteAfterReadLock() throws InterruptedException {
492	<	final CountDownLatch running = new CountDownLatch(1);
492	>	final CountDownLatch aboutToLock = new CountDownLatch(1);
493		final StampedLock lock = new StampedLock();
494		long rs = lock.readLock();
495		Thread t = newStartedThread(new CheckedRunnable() {
496		public void realRun() {
497	<	running.countDown();
497	>	aboutToLock.countDown();
498		long s = lock.writeLock();
499	+	assertTrue(lock.isWriteLocked());
500	+	assertFalse(lock.isReadLocked());
501		lock.unlockWrite(s);
502		}});
503
504	<	running.await();
505	<	waitForThreadToEnterWaitState(t, 100);
504	>	await(aboutToLock);
505	>	assertThreadBlocks(t, Thread.State.WAITING);
506		assertFalse(lock.isWriteLocked());
507	+	assertTrue(lock.isReadLocked());
508		lock.unlockRead(rs);
509		awaitTermination(t);
510	<	assertFalse(lock.isWriteLocked());
510	>	assertUnlocked(lock);
511		}
512
513		/**
514	<	* A writelock succeeds only after reading threads unlock
514	>	* writeLock() succeeds only after reading threads unlock
515		*/
516		public void testWriteAfterMultipleReadLocks() {
517		final StampedLock lock = new StampedLock();
#	Line 463 | Line 530 | public class StampedLockTest extends JSR
530		lock.unlockWrite(ws);
531		}});
532
533	+	assertTrue(lock.isReadLocked());
534		assertFalse(lock.isWriteLocked());
535		lock.unlockRead(s);
536		awaitTermination(t2);
537	<	assertFalse(lock.isWriteLocked());
537	>	assertUnlocked(lock);
538		}
539
540		/**
541	<	* Readlocks succeed only after a writing thread unlocks
541	>	* readLock() succeed only after a writing thread unlocks
542		*/
543		public void testReadAfterWriteLock() {
544		final StampedLock lock = new StampedLock();
545	+	final CountDownLatch threadsStarted = new CountDownLatch(2);
546		final long s = lock.writeLock();
547	<	Thread t1 = newStartedThread(new CheckedRunnable() {
479	<	public void realRun() {
480	<	long rs = lock.readLock();
481	<	lock.unlockRead(rs);
482	<	}});
483	<	Thread t2 = newStartedThread(new CheckedRunnable() {
547	>	final Runnable acquireReleaseReadLock = new CheckedRunnable() {
548		public void realRun() {
549	+	threadsStarted.countDown();
550		long rs = lock.readLock();
551	+	assertTrue(lock.isReadLocked());
552	+	assertFalse(lock.isWriteLocked());
553		lock.unlockRead(rs);
554	<	}});
555	<
554	>	}};
555	>	Thread t1 = newStartedThread(acquireReleaseReadLock);
556	>	Thread t2 = newStartedThread(acquireReleaseReadLock);
557	>
558	>	await(threadsStarted);
559	>	assertThreadBlocks(t1, Thread.State.WAITING);
560	>	assertThreadBlocks(t2, Thread.State.WAITING);
561	>	assertTrue(lock.isWriteLocked());
562	>	assertFalse(lock.isReadLocked());
563		releaseWriteLock(lock, s);
564		awaitTermination(t1);
565		awaitTermination(t2);
566	+	assertUnlocked(lock);
567		}
568
569		/**
570	<	* tryReadLock succeeds if readlocked but not writelocked
570	>	* tryReadLock succeeds if read locked but not write locked
571		*/
572		public void testTryLockWhenReadLocked() {
573		final StampedLock lock = new StampedLock();
#	Line 500 | Line 575 | public class StampedLockTest extends JSR
575		Thread t = newStartedThread(new CheckedRunnable() {
576		public void realRun() {
577		long rs = lock.tryReadLock();
578	<	threadAssertTrue(rs != 0L);
578	>	assertValid(lock, rs);
579		lock.unlockRead(rs);
580		}});
581
#	Line 509 | Line 584 | public class StampedLockTest extends JSR
584		}
585
586		/**
587	<	* tryWriteLock fails when readlocked
587	>	* tryWriteLock fails when read locked
588		*/
589	<	public void testWriteTryLockWhenReadLocked() {
589	>	public void testTryWriteLockWhenReadLocked() {
590		final StampedLock lock = new StampedLock();
591		long s = lock.readLock();
592		Thread t = newStartedThread(new CheckedRunnable() {
593		public void realRun() {
594	<	long ws = lock.tryWriteLock();
520	<	threadAssertEquals(ws, 0L);
594	>	assertEquals(0L, lock.tryWriteLock());
595		}});
596
597		awaitTermination(t);
#	Line 525 | Line 599 | public class StampedLockTest extends JSR
599		}
600
601		/**
602	<	* timed tryWriteLock times out if locked
602	>	* timed lock operations time out if lock not available
603		*/
604	<	public void testWriteTryLock_Timeout() {
604	>	public void testTimedLock_Timeout() throws Exception {
605	>	ArrayList<Future<?>> futures = new ArrayList<>();
606	>
607	>	// Write locked
608		final StampedLock lock = new StampedLock();
609	<	long s = lock.writeLock();
610	<	Thread t = newStartedThread(new CheckedRunnable() {
609	>	long stamp = lock.writeLock();
610	>	assertEquals(0L, lock.tryReadLock(0L, DAYS));
611	>	assertEquals(0L, lock.tryReadLock(Long.MIN_VALUE, DAYS));
612	>	assertFalse(lock.asReadLock().tryLock(0L, DAYS));
613	>	assertFalse(lock.asReadLock().tryLock(Long.MIN_VALUE, DAYS));
614	>	assertEquals(0L, lock.tryWriteLock(0L, DAYS));
615	>	assertEquals(0L, lock.tryWriteLock(Long.MIN_VALUE, DAYS));
616	>	assertFalse(lock.asWriteLock().tryLock(0L, DAYS));
617	>	assertFalse(lock.asWriteLock().tryLock(Long.MIN_VALUE, DAYS));
618	>
619	>	futures.add(cachedThreadPool.submit(new CheckedRunnable() {
620		public void realRun() throws InterruptedException {
621		long startTime = System.nanoTime();
622	<	long timeoutMillis = 10;
623	<	long ws = lock.tryWriteLock(timeoutMillis, MILLISECONDS);
624	<	assertEquals(ws, 0L);
539	<	assertTrue(millisElapsedSince(startTime) >= timeoutMillis);
540	<	}});
622	>	assertEquals(0L, lock.tryWriteLock(timeoutMillis(), MILLISECONDS));
623	>	assertTrue(millisElapsedSince(startTime) >= timeoutMillis());
624	>	}}));
625
626	<	awaitTermination(t);
627	<	releaseWriteLock(lock, s);
628	<	}
626	>	futures.add(cachedThreadPool.submit(new CheckedRunnable() {
627	>	public void realRun() throws InterruptedException {
628	>	long startTime = System.nanoTime();
629	>	assertEquals(0L, lock.tryReadLock(timeoutMillis(), MILLISECONDS));
630	>	assertTrue(millisElapsedSince(startTime) >= timeoutMillis());
631	>	}}));
632	>
633	>	// Read locked
634	>	final StampedLock lock2 = new StampedLock();
635	>	long stamp2 = lock2.readLock();
636	>	assertEquals(0L, lock2.tryWriteLock(0L, DAYS));
637	>	assertEquals(0L, lock2.tryWriteLock(Long.MIN_VALUE, DAYS));
638	>	assertFalse(lock2.asWriteLock().tryLock(0L, DAYS));
639	>	assertFalse(lock2.asWriteLock().tryLock(Long.MIN_VALUE, DAYS));
640
641	<	/**
547	<	* timed tryReadLock times out if write-locked
548	<	*/
549	<	public void testReadTryLock_Timeout() {
550	<	final StampedLock lock = new StampedLock();
551	<	long s = lock.writeLock();
552	<	Thread t = newStartedThread(new CheckedRunnable() {
641	>	futures.add(cachedThreadPool.submit(new CheckedRunnable() {
642		public void realRun() throws InterruptedException {
643		long startTime = System.nanoTime();
644	<	long timeoutMillis = 10;
645	<	long rs = lock.tryReadLock(timeoutMillis, MILLISECONDS);
646	<	assertEquals(rs, 0L);
558	<	assertTrue(millisElapsedSince(startTime) >= timeoutMillis);
559	<	}});
644	>	assertEquals(0L, lock2.tryWriteLock(timeoutMillis(), MILLISECONDS));
645	>	assertTrue(millisElapsedSince(startTime) >= timeoutMillis());
646	>	}}));
647
648	<	awaitTermination(t);
649	<	assertTrue(lock.isWriteLocked());
650	<	lock.unlockWrite(s);
648	>	for (Future<?> future : futures)
649	>	assertNull(future.get());
650	>
651	>	releaseWriteLock(lock, stamp);
652	>	releaseReadLock(lock2, stamp2);
653		}
654
655		/**
656	<	* writeLockInterruptibly succeeds if unlocked, else is interruptible
656	>	* writeLockInterruptibly succeeds if unlocked
657		*/
658		public void testWriteLockInterruptibly() throws InterruptedException {
570	–	final CountDownLatch running = new CountDownLatch(1);
659		final StampedLock lock = new StampedLock();
660		long s = lock.writeLockInterruptibly();
573	–	Thread t = newStartedThread(new CheckedInterruptedRunnable() {
574	–	public void realRun() throws InterruptedException {
575	–	running.countDown();
576	–	lock.writeLockInterruptibly();
577	–	}});
578	–
579	–	running.await();
580	–	waitForThreadToEnterWaitState(t, 100);
581	–	t.interrupt();
661		assertTrue(lock.isWriteLocked());
583	–	awaitTermination(t);
662		releaseWriteLock(lock, s);
663		}
664
665		/**
666	<	* readLockInterruptibly succeeds if lock free else is interruptible
666	>	* readLockInterruptibly succeeds if lock free
667		*/
668		public void testReadLockInterruptibly() throws InterruptedException {
591	–	final CountDownLatch running = new CountDownLatch(1);
669		final StampedLock lock = new StampedLock();
670	<	long s;
671	<	s = lock.readLockInterruptibly();
670	>
671	>	long s = assertValid(lock, lock.readLockInterruptibly());
672	>	assertTrue(lock.isReadLocked());
673		lock.unlockRead(s);
596	–	s = lock.writeLockInterruptibly();
597	–	Thread t = newStartedThread(new CheckedInterruptedRunnable() {
598	–	public void realRun() throws InterruptedException {
599	–	running.countDown();
600	–	lock.readLockInterruptibly();
601	–	}});
674
675	<	running.await();
676	<	waitForThreadToEnterWaitState(t, 100);
677	<	t.interrupt();
606	<	awaitTermination(t);
607	<	releaseWriteLock(lock, s);
675	>	lock.asReadLock().lockInterruptibly();
676	>	assertTrue(lock.isReadLocked());
677	>	lock.asReadLock().unlock();
678		}
679
680		/**
#	Line 633 | Line 703 | public class StampedLockTest extends JSR
703		lock.unlockWrite(s);
704		s = lock.readLock();
705		assertTrue(lock.toString().contains("Read-locks"));
706	+	releaseReadLock(lock, s);
707		}
708
709		/**
710	<	* tryOptimisticRead succeeds and validates if unlocked, fails if locked
710	>	* tryOptimisticRead succeeds and validates if unlocked, fails if
711	>	* exclusively locked
712		*/
713		public void testValidateOptimistic() throws InterruptedException {
714		StampedLock lock = new StampedLock();
715	<	long s, p;
716	<	assertTrue((p = lock.tryOptimisticRead()) != 0L);
717	<	assertTrue(lock.validate(p));
718	<	assertTrue((s = lock.writeLock()) != 0L);
719	<	assertFalse((p = lock.tryOptimisticRead()) != 0L);
720	<	assertTrue(lock.validate(s));
721	<	lock.unlockWrite(s);
722	<	assertTrue((p = lock.tryOptimisticRead()) != 0L);
723	<	assertTrue(lock.validate(p));
724	<	assertTrue((s = lock.readLock()) != 0L);
725	<	assertTrue(lock.validate(s));
726	<	assertTrue((p = lock.tryOptimisticRead()) != 0L);
727	<	assertTrue(lock.validate(p));
728	<	lock.unlockRead(s);
729	<	assertTrue((s = lock.tryWriteLock()) != 0L);
730	<	assertTrue(lock.validate(s));
731	<	assertFalse((p = lock.tryOptimisticRead()) != 0L);
660	<	lock.unlockWrite(s);
661	<	assertTrue((s = lock.tryReadLock()) != 0L);
662	<	assertTrue(lock.validate(s));
663	<	assertTrue((p = lock.tryOptimisticRead()) != 0L);
664	<	lock.unlockRead(s);
665	<	assertTrue(lock.validate(p));
666	<	assertTrue((s = lock.tryWriteLock(100L, MILLISECONDS)) != 0L);
667	<	assertFalse((p = lock.tryOptimisticRead()) != 0L);
668	<	assertTrue(lock.validate(s));
669	<	lock.unlockWrite(s);
670	<	assertTrue((s = lock.tryReadLock(100L, MILLISECONDS)) != 0L);
671	<	assertTrue(lock.validate(s));
672	<	assertTrue((p = lock.tryOptimisticRead()) != 0L);
673	<	lock.unlockRead(s);
674	<	assertTrue((p = lock.tryOptimisticRead()) != 0L);
715	>
716	>	assertValid(lock, lock.tryOptimisticRead());
717	>
718	>	for (Function<StampedLock, Long> writeLocker : writeLockers()) {
719	>	long s = assertValid(lock, writeLocker.apply(lock));
720	>	assertEquals(0L, lock.tryOptimisticRead());
721	>	releaseWriteLock(lock, s);
722	>	}
723	>
724	>	for (Function<StampedLock, Long> readLocker : readLockers()) {
725	>	long s = assertValid(lock, readLocker.apply(lock));
726	>	long p = assertValid(lock, lock.tryOptimisticRead());
727	>	releaseReadLock(lock, s);
728	>	assertTrue(lock.validate(p));
729	>	}
730	>
731	>	assertValid(lock, lock.tryOptimisticRead());
732		}
733
734		/**
735		* tryOptimisticRead stamp does not validate if a write lock intervenes
736		*/
737		public void testValidateOptimisticWriteLocked() {
738	<	StampedLock lock = new StampedLock();
739	<	long s, p;
740	<	assertTrue((p = lock.tryOptimisticRead()) != 0L);
684	<	assertTrue((s = lock.writeLock()) != 0L);
738	>	final StampedLock lock = new StampedLock();
739	>	final long p = assertValid(lock, lock.tryOptimisticRead());
740	>	final long s = assertValid(lock, lock.writeLock());
741		assertFalse(lock.validate(p));
742	<	assertFalse((p = lock.tryOptimisticRead()) != 0L);
742	>	assertEquals(0L, lock.tryOptimisticRead());
743		assertTrue(lock.validate(s));
744		lock.unlockWrite(s);
745		}
#	Line 694 | Line 750 | public class StampedLockTest extends JSR
750		*/
751		public void testValidateOptimisticWriteLocked2()
752		throws InterruptedException {
753	<	final CountDownLatch running = new CountDownLatch(1);
753	>	final CountDownLatch locked = new CountDownLatch(1);
754		final StampedLock lock = new StampedLock();
755	<	long s, p;
756	<	assertTrue((p = lock.tryOptimisticRead()) != 0L);
755	>	final long p = assertValid(lock, lock.tryOptimisticRead());
756	>
757		Thread t = newStartedThread(new CheckedInterruptedRunnable() {
758		public void realRun() throws InterruptedException {
759		lock.writeLockInterruptibly();
760	<	running.countDown();
760	>	locked.countDown();
761		lock.writeLockInterruptibly();
762		}});
763
764	<	running.await();
764	>	await(locked);
765		assertFalse(lock.validate(p));
766	<	assertFalse((p = lock.tryOptimisticRead()) != 0L);
766	>	assertEquals(0L, lock.tryOptimisticRead());
767	>	assertThreadBlocks(t, Thread.State.WAITING);
768		t.interrupt();
769		awaitTermination(t);
770	+	assertTrue(lock.isWriteLocked());
771		}
772
773		/**
774	<	* tryConvertToOptimisticRead succeeds and validates if successfully locked,
774	>	* tryConvertToOptimisticRead succeeds and validates if successfully locked
775		*/
776		public void testTryConvertToOptimisticRead() throws InterruptedException {
777		StampedLock lock = new StampedLock();
778	<	long s, p;
779	<	s = 0L;
780	<	assertFalse((p = lock.tryConvertToOptimisticRead(s)) != 0L);
781	<	assertTrue((s = lock.tryOptimisticRead()) != 0L);
782	<	assertTrue((p = lock.tryConvertToOptimisticRead(s)) != 0L);
725	<	assertTrue((s = lock.writeLock()) != 0L);
726	<	assertTrue((p = lock.tryConvertToOptimisticRead(s)) != 0L);
727	<	assertTrue(lock.validate(p));
728	<	assertTrue((s = lock.readLock()) != 0L);
729	<	assertTrue(lock.validate(s));
730	<	assertTrue((p = lock.tryConvertToOptimisticRead(s)) != 0L);
731	<	assertTrue(lock.validate(p));
732	<	assertTrue((s = lock.tryWriteLock()) != 0L);
733	<	assertTrue(lock.validate(s));
734	<	assertTrue((p = lock.tryConvertToOptimisticRead(s)) != 0L);
735	<	assertTrue(lock.validate(p));
736	<	assertTrue((s = lock.tryReadLock()) != 0L);
737	<	assertTrue(lock.validate(s));
738	<	assertTrue((p = lock.tryConvertToOptimisticRead(s)) != 0L);
739	<	assertTrue(lock.validate(p));
740	<	assertTrue((s = lock.tryWriteLock(100L, MILLISECONDS)) != 0L);
741	<	assertTrue((p = lock.tryConvertToOptimisticRead(s)) != 0L);
742	<	assertTrue(lock.validate(p));
743	<	assertTrue((s = lock.tryReadLock(100L, MILLISECONDS)) != 0L);
778	>	long s, p, q;
779	>	assertEquals(0L, lock.tryConvertToOptimisticRead(0L));
780	>
781	>	s = assertValid(lock, lock.tryOptimisticRead());
782	>	assertEquals(s, lock.tryConvertToOptimisticRead(s));
783		assertTrue(lock.validate(s));
784	<	assertTrue((p = lock.tryConvertToOptimisticRead(s)) != 0L);
785	<	assertTrue(lock.validate(p));
784	>
785	>	for (Function<StampedLock, Long> writeLocker : writeLockers()) {
786	>	s = assertValid(lock, writeLocker.apply(lock));
787	>	p = assertValid(lock, lock.tryConvertToOptimisticRead(s));
788	>	assertFalse(lock.validate(s));
789	>	assertTrue(lock.validate(p));
790	>	assertUnlocked(lock);
791	>	}
792	>
793	>	for (Function<StampedLock, Long> readLocker : readLockers()) {
794	>	s = assertValid(lock, readLocker.apply(lock));
795	>	q = assertValid(lock, lock.tryOptimisticRead());
796	>	assertEquals(q, lock.tryConvertToOptimisticRead(q));
797	>	assertTrue(lock.validate(q));
798	>	assertTrue(lock.isReadLocked());
799	>	p = assertValid(lock, lock.tryConvertToOptimisticRead(s));
800	>	assertTrue(lock.validate(p));
801	>	assertTrue(lock.validate(s));
802	>	assertUnlocked(lock);
803	>	assertEquals(q, lock.tryConvertToOptimisticRead(q));
804	>	assertTrue(lock.validate(q));
805	>	}
806		}
807
808		/**
809	<	* tryConvertToReadLock succeeds and validates if successfully locked
751	<	* or lock free;
809	>	* tryConvertToReadLock succeeds for valid stamps
810		*/
811		public void testTryConvertToReadLock() throws InterruptedException {
812		StampedLock lock = new StampedLock();
813		long s, p;
814	<	s = 0L;
815	<	assertFalse((p = lock.tryConvertToReadLock(s)) != 0L);
816	<	assertTrue((s = lock.tryOptimisticRead()) != 0L);
817	<	assertTrue((p = lock.tryConvertToReadLock(s)) != 0L);
818	<	lock.unlockRead(p);
819	<	assertTrue((s = lock.writeLock()) != 0L);
820	<	assertTrue((p = lock.tryConvertToReadLock(s)) != 0L);
763	<	assertTrue(lock.validate(p));
764	<	lock.unlockRead(p);
765	<	assertTrue((s = lock.readLock()) != 0L);
766	<	assertTrue(lock.validate(s));
767	<	assertTrue((p = lock.tryConvertToReadLock(s)) != 0L);
768	<	assertTrue(lock.validate(p));
769	<	lock.unlockRead(p);
770	<	assertTrue((s = lock.tryWriteLock()) != 0L);
771	<	assertTrue(lock.validate(s));
772	<	assertTrue((p = lock.tryConvertToReadLock(s)) != 0L);
773	<	assertTrue(lock.validate(p));
774	<	lock.unlockRead(p);
775	<	assertTrue((s = lock.tryReadLock()) != 0L);
814	>
815	>	assertEquals(0L, lock.tryConvertToReadLock(0L));
816	>
817	>	s = assertValid(lock, lock.tryOptimisticRead());
818	>	p = assertValid(lock, lock.tryConvertToReadLock(s));
819	>	assertTrue(lock.isReadLocked());
820	>	assertEquals(1, lock.getReadLockCount());
821		assertTrue(lock.validate(s));
777	–	assertTrue((p = lock.tryConvertToReadLock(s)) != 0L);
778	–	assertTrue(lock.validate(p));
822		lock.unlockRead(p);
823	<	assertTrue((s = lock.tryWriteLock(100L, MILLISECONDS)) != 0L);
824	<	assertTrue((p = lock.tryConvertToReadLock(s)) != 0L);
825	<	assertTrue(lock.validate(p));
823	>
824	>	s = assertValid(lock, lock.tryOptimisticRead());
825	>	lock.readLock();
826	>	p = assertValid(lock, lock.tryConvertToReadLock(s));
827	>	assertTrue(lock.isReadLocked());
828	>	assertEquals(2, lock.getReadLockCount());
829		lock.unlockRead(p);
784	–	assertTrue((s = lock.tryReadLock(100L, MILLISECONDS)) != 0L);
785	–	assertTrue(lock.validate(s));
786	–	assertTrue((p = lock.tryConvertToReadLock(s)) != 0L);
787	–	assertTrue(lock.validate(p));
830		lock.unlockRead(p);
831	+	assertUnlocked(lock);
832	+
833	+	for (BiConsumer<StampedLock, Long> readUnlocker : readUnlockers()) {
834	+	for (Function<StampedLock, Long> writeLocker : writeLockers()) {
835	+	s = assertValid(lock, writeLocker.apply(lock));
836	+	p = assertValid(lock, lock.tryConvertToReadLock(s));
837	+	assertFalse(lock.validate(s));
838	+	assertTrue(lock.isReadLocked());
839	+	assertEquals(1, lock.getReadLockCount());
840	+	readUnlocker.accept(lock, p);
841	+	}
842	+
843	+	for (Function<StampedLock, Long> readLocker : readLockers()) {
844	+	s = assertValid(lock, readLocker.apply(lock));
845	+	assertEquals(s, lock.tryConvertToReadLock(s));
846	+	assertTrue(lock.validate(s));
847	+	assertTrue(lock.isReadLocked());
848	+	assertEquals(1, lock.getReadLockCount());
849	+	readUnlocker.accept(lock, s);
850	+	}
851	+	}
852		}
853
854		/**
855	<	* tryConvertToWriteLock succeeds and validates if successfully locked
793	<	* or lock free;
855	>	* tryConvertToWriteLock succeeds if lock available; fails if multiply read locked
856		*/
857		public void testTryConvertToWriteLock() throws InterruptedException {
858		StampedLock lock = new StampedLock();
859		long s, p;
860	<	s = 0L;
861	<	assertFalse((p = lock.tryConvertToWriteLock(s)) != 0L);
860	>
861	>	assertEquals(0L, lock.tryConvertToWriteLock(0L));
862	>
863		assertTrue((s = lock.tryOptimisticRead()) != 0L);
864		assertTrue((p = lock.tryConvertToWriteLock(s)) != 0L);
865	+	assertTrue(lock.isWriteLocked());
866		lock.unlockWrite(p);
867	<	assertTrue((s = lock.writeLock()) != 0L);
868	<	assertTrue((p = lock.tryConvertToWriteLock(s)) != 0L);
869	<	assertTrue(lock.validate(p));
870	<	lock.unlockWrite(p);
871	<	assertTrue((s = lock.readLock()) != 0L);
872	<	assertTrue(lock.validate(s));
873	<	assertTrue((p = lock.tryConvertToWriteLock(s)) != 0L);
874	<	assertTrue(lock.validate(p));
875	<	lock.unlockWrite(p);
876	<	assertTrue((s = lock.tryWriteLock()) != 0L);
877	<	assertTrue(lock.validate(s));
878	<	assertTrue((p = lock.tryConvertToWriteLock(s)) != 0L);
879	<	assertTrue(lock.validate(p));
880	<	lock.unlockWrite(p);
881	<	assertTrue((s = lock.tryReadLock()) != 0L);
882	<	assertTrue(lock.validate(s));
883	<	assertTrue((p = lock.tryConvertToWriteLock(s)) != 0L);
884	<	assertTrue(lock.validate(p));
885	<	lock.unlockWrite(p);
886	<	assertTrue((s = lock.tryWriteLock(100L, MILLISECONDS)) != 0L);
887	<	assertTrue((p = lock.tryConvertToWriteLock(s)) != 0L);
888	<	assertTrue(lock.validate(p));
889	<	lock.unlockWrite(p);
890	<	assertTrue((s = lock.tryReadLock(100L, MILLISECONDS)) != 0L);
891	<	assertTrue(lock.validate(s));
892	<	assertTrue((p = lock.tryConvertToWriteLock(s)) != 0L);
893	<	assertTrue(lock.validate(p));
894	<	lock.unlockWrite(p);
867	>
868	>	for (BiConsumer<StampedLock, Long> writeUnlocker : writeUnlockers()) {
869	>	for (Function<StampedLock, Long> writeLocker : writeLockers()) {
870	>	s = assertValid(lock, writeLocker.apply(lock));
871	>	assertEquals(s, lock.tryConvertToWriteLock(s));
872	>	assertTrue(lock.validate(s));
873	>	assertTrue(lock.isWriteLocked());
874	>	writeUnlocker.accept(lock, s);
875	>	}
876	>
877	>	for (Function<StampedLock, Long> readLocker : readLockers()) {
878	>	s = assertValid(lock, readLocker.apply(lock));
879	>	p = assertValid(lock, lock.tryConvertToWriteLock(s));
880	>	assertFalse(lock.validate(s));
881	>	assertTrue(lock.validate(p));
882	>	assertTrue(lock.isWriteLocked());
883	>	writeUnlocker.accept(lock, p);
884	>	}
885	>	}
886	>
887	>	// failure if multiply read locked
888	>	for (Function<StampedLock, Long> readLocker : readLockers()) {
889	>	s = assertValid(lock, readLocker.apply(lock));
890	>	p = assertValid(lock, readLocker.apply(lock));
891	>	assertEquals(0L, lock.tryConvertToWriteLock(s));
892	>	assertTrue(lock.validate(s));
893	>	assertTrue(lock.validate(p));
894	>	assertEquals(2, lock.getReadLockCount());
895	>	lock.unlock(p);
896	>	lock.unlock(s);
897	>	assertUnlocked(lock);
898	>	}
899		}
900
901		/**
902		* asWriteLock can be locked and unlocked
903		*/
904	<	public void testAsWriteLock() {
904	>	public void testAsWriteLock() throws Throwable {
905		StampedLock sl = new StampedLock();
906		Lock lock = sl.asWriteLock();
907	<	lock.lock();
908	<	assertFalse(lock.tryLock());
909	<	lock.unlock();
910	<	assertTrue(lock.tryLock());
907	>	for (Action locker : lockLockers(lock)) {
908	>	locker.run();
909	>	assertTrue(sl.isWriteLocked());
910	>	assertFalse(sl.isReadLocked());
911	>	assertFalse(lock.tryLock());
912	>	lock.unlock();
913	>	assertUnlocked(sl);
914	>	}
915		}
916
917		/**
918		* asReadLock can be locked and unlocked
919		*/
920	<	public void testAsReadLock() {
920	>	public void testAsReadLock() throws Throwable {
921		StampedLock sl = new StampedLock();
922		Lock lock = sl.asReadLock();
923	<	lock.lock();
924	<	lock.unlock();
925	<	assertTrue(lock.tryLock());
923	>	for (Action locker : lockLockers(lock)) {
924	>	locker.run();
925	>	assertTrue(sl.isReadLocked());
926	>	assertFalse(sl.isWriteLocked());
927	>	assertEquals(1, sl.getReadLockCount());
928	>	locker.run();
929	>	assertTrue(sl.isReadLocked());
930	>	assertEquals(2, sl.getReadLockCount());
931	>	lock.unlock();
932	>	lock.unlock();
933	>	assertUnlocked(sl);
934	>	}
935		}
936
937		/**
938		* asReadWriteLock.writeLock can be locked and unlocked
939		*/
940	<	public void testAsReadWriteLockWriteLock() {
940	>	public void testAsReadWriteLockWriteLock() throws Throwable {
941		StampedLock sl = new StampedLock();
942		Lock lock = sl.asReadWriteLock().writeLock();
943	<	lock.lock();
944	<	assertFalse(lock.tryLock());
945	<	lock.unlock();
946	<	assertTrue(lock.tryLock());
943	>	for (Action locker : lockLockers(lock)) {
944	>	locker.run();
945	>	assertTrue(sl.isWriteLocked());
946	>	assertFalse(sl.isReadLocked());
947	>	assertFalse(lock.tryLock());
948	>	lock.unlock();
949	>	assertUnlocked(sl);
950	>	}
951		}
952
953		/**
954		* asReadWriteLock.readLock can be locked and unlocked
955		*/
956	<	public void testAsReadWriteLockReadLock() {
956	>	public void testAsReadWriteLockReadLock() throws Throwable {
957		StampedLock sl = new StampedLock();
958		Lock lock = sl.asReadWriteLock().readLock();
959	<	lock.lock();
960	<	lock.unlock();
961	<	assertTrue(lock.tryLock());
959	>	for (Action locker : lockLockers(lock)) {
960	>	locker.run();
961	>	assertTrue(sl.isReadLocked());
962	>	assertFalse(sl.isWriteLocked());
963	>	assertEquals(1, sl.getReadLockCount());
964	>	locker.run();
965	>	assertTrue(sl.isReadLocked());
966	>	assertEquals(2, sl.getReadLockCount());
967	>	lock.unlock();
968	>	lock.unlock();
969	>	assertUnlocked(sl);
970	>	}
971	>	}
972	>
973	>	/**
974	>	* Lock.newCondition throws UnsupportedOperationException
975	>	*/
976	>	public void testLockViewsDoNotSupportConditions() {
977	>	StampedLock sl = new StampedLock();
978	>	assertThrows(UnsupportedOperationException.class,
979	>	() -> sl.asWriteLock().newCondition(),
980	>	() -> sl.asReadLock().newCondition(),
981	>	() -> sl.asReadWriteLock().writeLock().newCondition(),
982	>	() -> sl.asReadWriteLock().readLock().newCondition());
983	>	}
984	>
985	>	/**
986	>	* Passing optimistic read stamps to unlock operations result in
987	>	* IllegalMonitorStateException
988	>	*/
989	>	public void testCannotUnlockOptimisticReadStamps() {
990	>	{
991	>	StampedLock sl = new StampedLock();
992	>	long stamp = assertValid(sl, sl.tryOptimisticRead());
993	>	assertThrows(IllegalMonitorStateException.class,
994	>	() -> sl.unlockRead(stamp));
995	>	}
996	>	{
997	>	StampedLock sl = new StampedLock();
998	>	long stamp = sl.tryOptimisticRead();
999	>	assertThrows(IllegalMonitorStateException.class,
1000	>	() -> sl.unlock(stamp));
1001	>	}
1002	>
1003	>	{
1004	>	StampedLock sl = new StampedLock();
1005	>	long stamp = sl.tryOptimisticRead();
1006	>	sl.writeLock();
1007	>	assertThrows(IllegalMonitorStateException.class,
1008	>	() -> sl.unlock(stamp));
1009	>	}
1010	>	{
1011	>	StampedLock sl = new StampedLock();
1012	>	sl.readLock();
1013	>	long stamp = assertValid(sl, sl.tryOptimisticRead());
1014	>	assertThrows(IllegalMonitorStateException.class,
1015	>	() -> sl.unlockRead(stamp));
1016	>	}
1017	>	{
1018	>	StampedLock sl = new StampedLock();
1019	>	sl.readLock();
1020	>	long stamp = assertValid(sl, sl.tryOptimisticRead());
1021	>	assertThrows(IllegalMonitorStateException.class,
1022	>	() -> sl.unlock(stamp));
1023	>	}
1024	>
1025	>	{
1026	>	StampedLock sl = new StampedLock();
1027	>	long stamp = sl.tryConvertToOptimisticRead(sl.writeLock());
1028	>	assertValid(sl, stamp);
1029	>	sl.writeLock();
1030	>	assertThrows(IllegalMonitorStateException.class,
1031	>	() -> sl.unlockWrite(stamp));
1032	>	}
1033	>	{
1034	>	StampedLock sl = new StampedLock();
1035	>	long stamp = sl.tryConvertToOptimisticRead(sl.writeLock());
1036	>	sl.writeLock();
1037	>	assertThrows(IllegalMonitorStateException.class,
1038	>	() -> sl.unlock(stamp));
1039	>	}
1040	>	{
1041	>	StampedLock sl = new StampedLock();
1042	>	long stamp = sl.tryConvertToOptimisticRead(sl.writeLock());
1043	>	sl.readLock();
1044	>	assertThrows(IllegalMonitorStateException.class,
1045	>	() -> sl.unlockRead(stamp));
1046	>	}
1047	>	{
1048	>	StampedLock sl = new StampedLock();
1049	>	long stamp = sl.tryConvertToOptimisticRead(sl.writeLock());
1050	>	sl.readLock();
1051	>	assertThrows(IllegalMonitorStateException.class,
1052	>	() -> sl.unlock(stamp));
1053	>	}
1054	>
1055	>	{
1056	>	StampedLock sl = new StampedLock();
1057	>	long stamp = sl.tryConvertToOptimisticRead(sl.readLock());
1058	>	assertValid(sl, stamp);
1059	>	sl.writeLock();
1060	>	assertThrows(IllegalMonitorStateException.class,
1061	>	() -> sl.unlockWrite(stamp));
1062	>	}
1063	>	{
1064	>	StampedLock sl = new StampedLock();
1065	>	long stamp = sl.tryConvertToOptimisticRead(sl.readLock());
1066	>	sl.writeLock();
1067	>	assertThrows(IllegalMonitorStateException.class,
1068	>	() -> sl.unlock(stamp));
1069	>	}
1070	>	{
1071	>	StampedLock sl = new StampedLock();
1072	>	long stamp = sl.tryConvertToOptimisticRead(sl.readLock());
1073	>	sl.readLock();
1074	>	assertThrows(IllegalMonitorStateException.class,
1075	>	() -> sl.unlockRead(stamp));
1076	>	}
1077	>	{
1078	>	StampedLock sl = new StampedLock();
1079	>	sl.readLock();
1080	>	long stamp = sl.tryConvertToOptimisticRead(sl.readLock());
1081	>	assertValid(sl, stamp);
1082	>	sl.readLock();
1083	>	assertThrows(IllegalMonitorStateException.class,
1084	>	() -> sl.unlockRead(stamp));
1085	>	}
1086	>	{
1087	>	StampedLock sl = new StampedLock();
1088	>	long stamp = sl.tryConvertToOptimisticRead(sl.readLock());
1089	>	sl.readLock();
1090	>	assertThrows(IllegalMonitorStateException.class,
1091	>	() -> sl.unlock(stamp));
1092	>	}
1093	>	{
1094	>	StampedLock sl = new StampedLock();
1095	>	sl.readLock();
1096	>	long stamp = sl.tryConvertToOptimisticRead(sl.readLock());
1097	>	sl.readLock();
1098	>	assertThrows(IllegalMonitorStateException.class,
1099	>	() -> sl.unlock(stamp));
1100	>	}
1101	>	}
1102	>
1103	>	static long writeLockInterruptiblyUninterrupted(StampedLock sl) {
1104	>	try { return sl.writeLockInterruptibly(); }
1105	>	catch (InterruptedException ex) { throw new AssertionError(ex); }
1106	>	}
1107	>
1108	>	static long tryWriteLockUninterrupted(StampedLock sl, long time, TimeUnit unit) {
1109	>	try { return sl.tryWriteLock(time, unit); }
1110	>	catch (InterruptedException ex) { throw new AssertionError(ex); }
1111	>	}
1112	>
1113	>	static long readLockInterruptiblyUninterrupted(StampedLock sl) {
1114	>	try { return sl.readLockInterruptibly(); }
1115	>	catch (InterruptedException ex) { throw new AssertionError(ex); }
1116	>	}
1117	>
1118	>	static long tryReadLockUninterrupted(StampedLock sl, long time, TimeUnit unit) {
1119	>	try { return sl.tryReadLock(time, unit); }
1120	>	catch (InterruptedException ex) { throw new AssertionError(ex); }
1121	>	}
1122	>
1123	>	/**
1124	>	* Invalid stamps result in IllegalMonitorStateException
1125	>	*/
1126	>	public void testInvalidStampsThrowIllegalMonitorStateException() {
1127	>	final StampedLock sl = new StampedLock();
1128	>
1129	>	assertThrows(IllegalMonitorStateException.class,
1130	>	() -> sl.unlockWrite(0L),
1131	>	() -> sl.unlockRead(0L),
1132	>	() -> sl.unlock(0L));
1133	>
1134	>	final long optimisticStamp = sl.tryOptimisticRead();
1135	>	final long readStamp = sl.readLock();
1136	>	sl.unlockRead(readStamp);
1137	>	final long writeStamp = sl.writeLock();
1138	>	sl.unlockWrite(writeStamp);
1139	>	assertTrue(optimisticStamp != 0L && readStamp != 0L && writeStamp != 0L);
1140	>	final long[] noLongerValidStamps = { optimisticStamp, readStamp, writeStamp };
1141	>	final Runnable assertNoLongerValidStampsThrow = () -> {
1142	>	for (long noLongerValidStamp : noLongerValidStamps)
1143	>	assertThrows(IllegalMonitorStateException.class,
1144	>	() -> sl.unlockWrite(noLongerValidStamp),
1145	>	() -> sl.unlockRead(noLongerValidStamp),
1146	>	() -> sl.unlock(noLongerValidStamp));
1147	>	};
1148	>	assertNoLongerValidStampsThrow.run();
1149	>
1150	>	for (Function<StampedLock, Long> readLocker : readLockers())
1151	>	for (BiConsumer<StampedLock, Long> readUnlocker : readUnlockers()) {
1152	>	final long stamp = readLocker.apply(sl);
1153	>	assertValid(sl, stamp);
1154	>	assertNoLongerValidStampsThrow.run();
1155	>	assertThrows(IllegalMonitorStateException.class,
1156	>	() -> sl.unlockWrite(stamp),
1157	>	() -> sl.unlockRead(sl.tryOptimisticRead()),
1158	>	() -> sl.unlockRead(0L));
1159	>	readUnlocker.accept(sl, stamp);
1160	>	assertUnlocked(sl);
1161	>	assertNoLongerValidStampsThrow.run();
1162	>	}
1163	>
1164	>	for (Function<StampedLock, Long> writeLocker : writeLockers())
1165	>	for (BiConsumer<StampedLock, Long> writeUnlocker : writeUnlockers()) {
1166	>	final long stamp = writeLocker.apply(sl);
1167	>	assertValid(sl, stamp);
1168	>	assertNoLongerValidStampsThrow.run();
1169	>	assertThrows(IllegalMonitorStateException.class,
1170	>	() -> sl.unlockRead(stamp),
1171	>	() -> sl.unlockWrite(0L));
1172	>	writeUnlocker.accept(sl, stamp);
1173	>	assertUnlocked(sl);
1174	>	assertNoLongerValidStampsThrow.run();
1175	>	}
1176	>	}
1177	>
1178	>	/**
1179	>	* Read locks can be very deeply nested
1180	>	*/
1181	>	public void testDeeplyNestedReadLocks() {
1182	>	final StampedLock lock = new StampedLock();
1183	>	final int depth = 300;
1184	>	final long[] stamps = new long[depth];
1185	>	final List<Function<StampedLock, Long>> readLockers = readLockers();
1186	>	final List<BiConsumer<StampedLock, Long>> readUnlockers = readUnlockers();
1187	>	for (int i = 0; i < depth; i++) {
1188	>	Function<StampedLock, Long> readLocker
1189	>	= readLockers.get(i % readLockers.size());
1190	>	long stamp = readLocker.apply(lock);
1191	>	assertEquals(i + 1, lock.getReadLockCount());
1192	>	assertTrue(lock.isReadLocked());
1193	>	stamps[i] = stamp;
1194	>	}
1195	>	for (int i = 0; i < depth; i++) {
1196	>	BiConsumer<StampedLock, Long> readUnlocker
1197	>	= readUnlockers.get(i % readUnlockers.size());
1198	>	assertEquals(depth - i, lock.getReadLockCount());
1199	>	assertTrue(lock.isReadLocked());
1200	>	readUnlocker.accept(lock, stamps[depth - 1 - i]);
1201	>	}
1202	>	assertUnlocked(lock);
1203	>	}
1204	>
1205	>	/**
1206	>	* Stamped locks are not reentrant.
1207	>	*/
1208	>	public void testNonReentrant() throws InterruptedException {
1209	>	final StampedLock lock = new StampedLock();
1210	>	long stamp;
1211	>
1212	>	stamp = lock.writeLock();
1213	>	assertValid(lock, stamp);
1214	>	assertEquals(0L, lock.tryWriteLock(0L, DAYS));
1215	>	assertEquals(0L, lock.tryReadLock(0L, DAYS));
1216	>	assertValid(lock, stamp);
1217	>	lock.unlockWrite(stamp);
1218	>
1219	>	stamp = lock.tryWriteLock(1L, DAYS);
1220	>	assertEquals(0L, lock.tryWriteLock(0L, DAYS));
1221	>	assertValid(lock, stamp);
1222	>	lock.unlockWrite(stamp);
1223	>
1224	>	stamp = lock.readLock();
1225	>	assertEquals(0L, lock.tryWriteLock(0L, DAYS));
1226	>	assertValid(lock, stamp);
1227	>	lock.unlockRead(stamp);
1228	>	}
1229	>
1230	>	/**
1231	>	* """StampedLocks have no notion of ownership. Locks acquired in
1232	>	* one thread can be released or converted in another."""
1233	>	*/
1234	>	public void testNoOwnership() throws Throwable {
1235	>	ArrayList<Future<?>> futures = new ArrayList<>();
1236	>	for (Function<StampedLock, Long> writeLocker : writeLockers())
1237	>	for (BiConsumer<StampedLock, Long> writeUnlocker : writeUnlockers()) {
1238	>	StampedLock lock = new StampedLock();
1239	>	long stamp = writeLocker.apply(lock);
1240	>	futures.add(cachedThreadPool.submit(new CheckedRunnable() {
1241	>	public void realRun() {
1242	>	writeUnlocker.accept(lock, stamp);
1243	>	assertUnlocked(lock);
1244	>	assertFalse(lock.validate(stamp));
1245	>	}}));
1246	>	}
1247	>	for (Future<?> future : futures)
1248	>	assertNull(future.get());
1249	>	}
1250	>
1251	>	/** Tries out sample usage code from StampedLock javadoc. */
1252	>	public void testSampleUsage() throws Throwable {
1253	>	class Point {
1254	>	private double x, y;
1255	>	private final StampedLock sl = new StampedLock();
1256	>
1257	>	void move(double deltaX, double deltaY) { // an exclusively locked method
1258	>	long stamp = sl.writeLock();
1259	>	try {
1260	>	x += deltaX;
1261	>	y += deltaY;
1262	>	} finally {
1263	>	sl.unlockWrite(stamp);
1264	>	}
1265	>	}
1266	>
1267	>	double distanceFromOrigin() { // A read-only method
1268	>	double currentX, currentY;
1269	>	long stamp = sl.tryOptimisticRead();
1270	>	do {
1271	>	if (stamp == 0L)
1272	>	stamp = sl.readLock();
1273	>	try {
1274	>	// possibly racy reads
1275	>	currentX = x;
1276	>	currentY = y;
1277	>	} finally {
1278	>	stamp = sl.tryConvertToOptimisticRead(stamp);
1279	>	}
1280	>	} while (stamp == 0);
1281	>	return Math.hypot(currentX, currentY);
1282	>	}
1283	>
1284	>	double distanceFromOrigin2() {
1285	>	long stamp = sl.tryOptimisticRead();
1286	>	try {
1287	>	retryHoldingLock:
1288	>	for (;; stamp = sl.readLock()) {
1289	>	if (stamp == 0L)
1290	>	continue retryHoldingLock;
1291	>	// possibly racy reads
1292	>	double currentX = x;
1293	>	double currentY = y;
1294	>	if (!sl.validate(stamp))
1295	>	continue retryHoldingLock;
1296	>	return Math.hypot(currentX, currentY);
1297	>	}
1298	>	} finally {
1299	>	if (StampedLock.isReadLockStamp(stamp))
1300	>	sl.unlockRead(stamp);
1301	>	}
1302	>	}
1303	>
1304	>	void moveIfAtOrigin(double newX, double newY) {
1305	>	long stamp = sl.readLock();
1306	>	try {
1307	>	while (x == 0.0 && y == 0.0) {
1308	>	long ws = sl.tryConvertToWriteLock(stamp);
1309	>	if (ws != 0L) {
1310	>	stamp = ws;
1311	>	x = newX;
1312	>	y = newY;
1313	>	return;
1314	>	}
1315	>	else {
1316	>	sl.unlockRead(stamp);
1317	>	stamp = sl.writeLock();
1318	>	}
1319	>	}
1320	>	} finally {
1321	>	sl.unlock(stamp);
1322	>	}
1323	>	}
1324	>	}
1325	>
1326	>	Point p = new Point();
1327	>	p.move(3.0, 4.0);
1328	>	assertEquals(5.0, p.distanceFromOrigin());
1329	>	p.moveIfAtOrigin(5.0, 12.0);
1330	>	assertEquals(5.0, p.distanceFromOrigin2());
1331	>	}
1332	>
1333	>	/**
1334	>	* Stamp inspection methods work as expected, and do not inspect
1335	>	* the state of the lock itself.
1336	>	*/
1337	>	public void testStampStateInspectionMethods() {
1338	>	StampedLock lock = new StampedLock();
1339	>
1340	>	assertFalse(isWriteLockStamp(0L));
1341	>	assertFalse(isReadLockStamp(0L));
1342	>	assertFalse(isLockStamp(0L));
1343	>	assertFalse(isOptimisticReadStamp(0L));
1344	>
1345	>	{
1346	>	long stamp = lock.writeLock();
1347	>	for (int i = 0; i < 2; i++) {
1348	>	assertTrue(isWriteLockStamp(stamp));
1349	>	assertFalse(isReadLockStamp(stamp));
1350	>	assertTrue(isLockStamp(stamp));
1351	>	assertFalse(isOptimisticReadStamp(stamp));
1352	>	if (i == 0)
1353	>	lock.unlockWrite(stamp);
1354	>	}
1355	>	}
1356	>
1357	>	{
1358	>	long stamp = lock.readLock();
1359	>	for (int i = 0; i < 2; i++) {
1360	>	assertFalse(isWriteLockStamp(stamp));
1361	>	assertTrue(isReadLockStamp(stamp));
1362	>	assertTrue(isLockStamp(stamp));
1363	>	assertFalse(isOptimisticReadStamp(stamp));
1364	>	if (i == 0)
1365	>	lock.unlockRead(stamp);
1366	>	}
1367	>	}
1368	>
1369	>	{
1370	>	long optimisticStamp = lock.tryOptimisticRead();
1371	>	long readStamp = lock.tryConvertToReadLock(optimisticStamp);
1372	>	long writeStamp = lock.tryConvertToWriteLock(readStamp);
1373	>	for (int i = 0; i < 2; i++) {
1374	>	assertFalse(isWriteLockStamp(optimisticStamp));
1375	>	assertFalse(isReadLockStamp(optimisticStamp));
1376	>	assertFalse(isLockStamp(optimisticStamp));
1377	>	assertTrue(isOptimisticReadStamp(optimisticStamp));
1378	>
1379	>	assertFalse(isWriteLockStamp(readStamp));
1380	>	assertTrue(isReadLockStamp(readStamp));
1381	>	assertTrue(isLockStamp(readStamp));
1382	>	assertFalse(isOptimisticReadStamp(readStamp));
1383	>
1384	>	assertTrue(isWriteLockStamp(writeStamp));
1385	>	assertFalse(isReadLockStamp(writeStamp));
1386	>	assertTrue(isLockStamp(writeStamp));
1387	>	assertFalse(isOptimisticReadStamp(writeStamp));
1388	>	if (i == 0)
1389	>	lock.unlockWrite(writeStamp);
1390	>	}
1391	>	}
1392	>	}
1393	>
1394	>	/**
1395	>	* Multiple threads repeatedly contend for the same lock.
1396	>	*/
1397	>	public void testConcurrentAccess() throws Exception {
1398	>	final StampedLock sl = new StampedLock();
1399	>	final Lock wl = sl.asWriteLock();
1400	>	final Lock rl = sl.asReadLock();
1401	>	final long testDurationMillis = expensiveTests ? 1000 : 2;
1402	>	final int nTasks = ThreadLocalRandom.current().nextInt(1, 10);
1403	>	final AtomicBoolean done = new AtomicBoolean(false);
1404	>	final List<CompletableFuture<?>> futures = new ArrayList<>();
1405	>	final List<Callable<Long>> stampedWriteLockers = List.of(
1406	>	() -> sl.writeLock(),
1407	>	() -> writeLockInterruptiblyUninterrupted(sl),
1408	>	() -> tryWriteLockUninterrupted(sl, LONG_DELAY_MS, MILLISECONDS),
1409	>	() -> {
1410	>	long stamp;
1411	>	do { stamp = sl.tryConvertToWriteLock(sl.tryOptimisticRead()); }
1412	>	while (stamp == 0L);
1413	>	return stamp;
1414	>	},
1415	>	() -> {
1416	>	long stamp;
1417	>	do { stamp = sl.tryWriteLock(); } while (stamp == 0L);
1418	>	return stamp;
1419	>	},
1420	>	() -> {
1421	>	long stamp;
1422	>	do { stamp = sl.tryWriteLock(0L, DAYS); } while (stamp == 0L);
1423	>	return stamp;
1424	>	});
1425	>	final List<Callable<Long>> stampedReadLockers = List.of(
1426	>	() -> sl.readLock(),
1427	>	() -> readLockInterruptiblyUninterrupted(sl),
1428	>	() -> tryReadLockUninterrupted(sl, LONG_DELAY_MS, MILLISECONDS),
1429	>	() -> {
1430	>	long stamp;
1431	>	do { stamp = sl.tryConvertToReadLock(sl.tryOptimisticRead()); }
1432	>	while (stamp == 0L);
1433	>	return stamp;
1434	>	},
1435	>	() -> {
1436	>	long stamp;
1437	>	do { stamp = sl.tryReadLock(); } while (stamp == 0L);
1438	>	return stamp;
1439	>	},
1440	>	() -> {
1441	>	long stamp;
1442	>	do { stamp = sl.tryReadLock(0L, DAYS); } while (stamp == 0L);
1443	>	return stamp;
1444	>	});
1445	>	final List<Consumer<Long>> stampedWriteUnlockers = List.of(
1446	>	stamp -> sl.unlockWrite(stamp),
1447	>	stamp -> sl.unlock(stamp),
1448	>	stamp -> assertTrue(sl.tryUnlockWrite()),
1449	>	stamp -> wl.unlock(),
1450	>	stamp -> sl.tryConvertToOptimisticRead(stamp));
1451	>	final List<Consumer<Long>> stampedReadUnlockers = List.of(
1452	>	stamp -> sl.unlockRead(stamp),
1453	>	stamp -> sl.unlock(stamp),
1454	>	stamp -> assertTrue(sl.tryUnlockRead()),
1455	>	stamp -> rl.unlock(),
1456	>	stamp -> sl.tryConvertToOptimisticRead(stamp));
1457	>	final Action writer = () -> {
1458	>	// repeatedly acquires write lock
1459	>	var locker = chooseRandomly(stampedWriteLockers);
1460	>	var unlocker = chooseRandomly(stampedWriteUnlockers);
1461	>	while (!done.getAcquire()) {
1462	>	long stamp = locker.call();
1463	>	try {
1464	>	assertTrue(isWriteLockStamp(stamp));
1465	>	assertTrue(sl.isWriteLocked());
1466	>	assertFalse(isReadLockStamp(stamp));
1467	>	assertFalse(sl.isReadLocked());
1468	>	assertEquals(0, sl.getReadLockCount());
1469	>	assertTrue(sl.validate(stamp));
1470	>	} finally {
1471	>	unlocker.accept(stamp);
1472	>	}
1473	>	}
1474	>	};
1475	>	final Action reader = () -> {
1476	>	// repeatedly acquires read lock
1477	>	var locker = chooseRandomly(stampedReadLockers);
1478	>	var unlocker = chooseRandomly(stampedReadUnlockers);
1479	>	while (!done.getAcquire()) {
1480	>	long stamp = locker.call();
1481	>	try {
1482	>	assertFalse(isWriteLockStamp(stamp));
1483	>	assertFalse(sl.isWriteLocked());
1484	>	assertTrue(isReadLockStamp(stamp));
1485	>	assertTrue(sl.isReadLocked());
1486	>	assertTrue(sl.getReadLockCount() > 0);
1487	>	assertTrue(sl.validate(stamp));
1488	>	} finally {
1489	>	unlocker.accept(stamp);
1490	>	}
1491	>	}
1492	>	};
1493	>	for (int i = nTasks; i--> 0; ) {
1494	>	Action task = chooseRandomly(writer, reader);
1495	>	futures.add(CompletableFuture.runAsync(checkedRunnable(task)));
1496	>	}
1497	>	Thread.sleep(testDurationMillis);
1498	>	done.setRelease(true);
1499	>	for (var future : futures)
1500	>	checkTimedGet(future, null);
1501		}
1502
1503		}

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