/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
/*
* This file is available under and governed by the GNU General Public
* License version 2 only, as published by the Free Software Foundation.
* However, the following notice accompanied the original version of this
* file:
*
* Written by Doug Lea with assistance from members of JCP JSR-166
* Expert Group and released to the public domain, as explained at
* http://creativecommons.org/publicdomain/zero/1.0/
* Other contributors include John Vint
*/
import static java.util.concurrent.TimeUnit.MILLISECONDS;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import java.util.NoSuchElementException;
import java.util.Queue;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.Executors;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.LinkedTransferQueue;
import junit.framework.Test;
@SuppressWarnings({"unchecked", "rawtypes"})
public class LinkedTransferQueueTest extends JSR166TestCase {
public static class Generic extends BlockingQueueTest {
protected BlockingQueue emptyCollection() {
return new LinkedTransferQueue();
}
}
public static void main(String[] args) {
main(suite(), args);
}
public static Test suite() {
class Implementation implements CollectionImplementation {
public Class<?> klazz() { return LinkedTransferQueue.class; }
public Collection emptyCollection() { return new LinkedTransferQueue(); }
public Object makeElement(int i) { return i; }
public boolean isConcurrent() { return true; }
public boolean permitsNulls() { return false; }
}
return newTestSuite(LinkedTransferQueueTest.class,
new Generic().testSuite(),
CollectionTest.testSuite(new Implementation()));
}
/**
* Constructor builds new queue with size being zero and empty
* being true
*/
public void testConstructor1() {
assertEquals(0, new LinkedTransferQueue().size());
assertTrue(new LinkedTransferQueue().isEmpty());
}
/**
* Initializing constructor with null collection throws
* NullPointerException
*/
public void testConstructor2() {
try {
new LinkedTransferQueue(null);
shouldThrow();
} catch (NullPointerException success) {}
}
/**
* Initializing from Collection of null elements throws
* NullPointerException
*/
public void testConstructor3() {
Collection<Integer> elements = Arrays.asList(new Integer[SIZE]);
try {
new LinkedTransferQueue(elements);
shouldThrow();
} catch (NullPointerException success) {}
}
/**
* Initializing constructor with a collection containing some null elements
* throws NullPointerException
*/
public void testConstructor4() {
Integer[] ints = new Integer[SIZE];
for (int i = 0; i < SIZE - 1; ++i)
ints[i] = i;
Collection<Integer> elements = Arrays.asList(ints);
try {
new LinkedTransferQueue(elements);
shouldThrow();
} catch (NullPointerException success) {}
}
/**
* Queue contains all elements of the collection it is initialized by
*/
public void testConstructor5() {
Integer[] ints = new Integer[SIZE];
for (int i = 0; i < SIZE; ++i) {
ints[i] = i;
}
List intList = Arrays.asList(ints);
LinkedTransferQueue q
= new LinkedTransferQueue(intList);
assertEquals(q.size(), intList.size());
assertEquals(q.toString(), intList.toString());
assertTrue(Arrays.equals(q.toArray(),
intList.toArray()));
assertTrue(Arrays.equals(q.toArray(new Object[0]),
intList.toArray(new Object[0])));
assertTrue(Arrays.equals(q.toArray(new Object[SIZE]),
intList.toArray(new Object[SIZE])));
for (int i = 0; i < SIZE; ++i) {
assertEquals(ints[i], q.poll());
}
}
/**
* remainingCapacity() always returns Integer.MAX_VALUE
*/
public void testRemainingCapacity() {
BlockingQueue q = populatedQueue(SIZE);
for (int i = 0; i < SIZE; ++i) {
assertEquals(Integer.MAX_VALUE, q.remainingCapacity());
assertEquals(SIZE - i, q.size());
assertEquals(i, q.remove());
}
for (int i = 0; i < SIZE; ++i) {
assertEquals(Integer.MAX_VALUE, q.remainingCapacity());
assertEquals(i, q.size());
assertTrue(q.add(i));
}
}
/**
* addAll(this) throws IllegalArgumentException
*/
public void testAddAllSelf() {
LinkedTransferQueue q = populatedQueue(SIZE);
try {
q.addAll(q);
shouldThrow();
} catch (IllegalArgumentException success) {}
}
/**
* addAll of a collection with any null elements throws
* NullPointerException after possibly adding some elements
*/
public void testAddAll3() {
LinkedTransferQueue q = new LinkedTransferQueue();
Integer[] ints = new Integer[SIZE];
for (int i = 0; i < SIZE - 1; ++i)
ints[i] = i;
try {
q.addAll(Arrays.asList(ints));
shouldThrow();
} catch (NullPointerException success) {}
}
/**
* Queue contains all elements, in traversal order, of successful addAll
*/
public void testAddAll5() {
Integer[] empty = new Integer[0];
Integer[] ints = new Integer[SIZE];
for (int i = 0; i < SIZE; ++i) {
ints[i] = i;
}
LinkedTransferQueue q = new LinkedTransferQueue();
assertFalse(q.addAll(Arrays.asList(empty)));
assertTrue(q.addAll(Arrays.asList(ints)));
for (int i = 0; i < SIZE; ++i) {
assertEquals(ints[i], q.poll());
}
}
/**
* all elements successfully put are contained
*/
public void testPut() {
LinkedTransferQueue<Integer> q = new LinkedTransferQueue<Integer>();
for (int i = 0; i < SIZE; ++i) {
assertEquals(i, q.size());
q.put(i);
assertTrue(q.contains(i));
}
}
/**
* take retrieves elements in FIFO order
*/
public void testTake() throws InterruptedException {
LinkedTransferQueue<Integer> q = populatedQueue(SIZE);
for (int i = 0; i < SIZE; ++i) {
assertEquals(i, (int) q.take());
}
}
/**
* take removes existing elements until empty, then blocks interruptibly
*/
public void testBlockingTake() throws InterruptedException {
final BlockingQueue q = populatedQueue(SIZE);
final CountDownLatch pleaseInterrupt = new CountDownLatch(1);
Thread t = newStartedThread(new CheckedRunnable() {
public void realRun() throws InterruptedException {
for (int i = 0; i < SIZE; ++i) {
assertEquals(i, q.take());
}
Thread.currentThread().interrupt();
try {
q.take();
shouldThrow();
} catch (InterruptedException success) {}
assertFalse(Thread.interrupted());
pleaseInterrupt.countDown();
try {
q.take();
shouldThrow();
} catch (InterruptedException success) {}
assertFalse(Thread.interrupted());
}});
await(pleaseInterrupt);
assertThreadStaysAlive(t);
t.interrupt();
awaitTermination(t);
}
/**
* poll succeeds unless empty
*/
public void testPoll() throws InterruptedException {
LinkedTransferQueue<Integer> q = populatedQueue(SIZE);
for (int i = 0; i < SIZE; ++i) {
assertEquals(i, (int) q.poll());
}
assertNull(q.poll());
checkEmpty(q);
}
/**
* timed poll with zero timeout succeeds when non-empty, else times out
*/
public void testTimedPoll0() throws InterruptedException {
LinkedTransferQueue<Integer> q = populatedQueue(SIZE);
for (int i = 0; i < SIZE; ++i) {
assertEquals(i, (int) q.poll(0, MILLISECONDS));
}
assertNull(q.poll(0, MILLISECONDS));
checkEmpty(q);
}
/**
* timed poll with nonzero timeout succeeds when non-empty, else times out
*/
public void testTimedPoll() throws InterruptedException {
LinkedTransferQueue<Integer> q = populatedQueue(SIZE);
long startTime = System.nanoTime();
for (int i = 0; i < SIZE; ++i)
assertEquals(i, (int) q.poll(LONG_DELAY_MS, MILLISECONDS));
assertTrue(millisElapsedSince(startTime) < LONG_DELAY_MS);
startTime = System.nanoTime();
assertNull(q.poll(timeoutMillis(), MILLISECONDS));
assertTrue(millisElapsedSince(startTime) >= timeoutMillis());
checkEmpty(q);
}
/**
* Interrupted timed poll throws InterruptedException instead of
* returning timeout status
*/
public void testInterruptedTimedPoll() throws InterruptedException {
final BlockingQueue<Integer> q = populatedQueue(SIZE);
final CountDownLatch aboutToWait = new CountDownLatch(1);
Thread t = newStartedThread(new CheckedRunnable() {
public void realRun() throws InterruptedException {
long startTime = System.nanoTime();
for (int i = 0; i < SIZE; ++i)
assertEquals(i, (int) q.poll(LONG_DELAY_MS, MILLISECONDS));
aboutToWait.countDown();
try {
q.poll(LONG_DELAY_MS, MILLISECONDS);
shouldThrow();
} catch (InterruptedException success) {}
assertTrue(millisElapsedSince(startTime) < LONG_DELAY_MS);
}});
aboutToWait.await();
waitForThreadToEnterWaitState(t);
t.interrupt();
awaitTermination(t);
checkEmpty(q);
}
/**
* timed poll after thread interrupted throws InterruptedException
* instead of returning timeout status
*/
public void testTimedPollAfterInterrupt() throws InterruptedException {
final BlockingQueue<Integer> q = populatedQueue(SIZE);
Thread t = newStartedThread(new CheckedRunnable() {
public void realRun() throws InterruptedException {
long startTime = System.nanoTime();
Thread.currentThread().interrupt();
for (int i = 0; i < SIZE; ++i)
assertEquals(i, (int) q.poll(LONG_DELAY_MS, MILLISECONDS));
try {
q.poll(LONG_DELAY_MS, MILLISECONDS);
shouldThrow();
} catch (InterruptedException success) {}
assertTrue(millisElapsedSince(startTime) < LONG_DELAY_MS);
}});
awaitTermination(t);
checkEmpty(q);
}
/**
* peek returns next element, or null if empty
*/
public void testPeek() throws InterruptedException {
LinkedTransferQueue<Integer> q = populatedQueue(SIZE);
for (int i = 0; i < SIZE; ++i) {
assertEquals(i, (int) q.peek());
assertEquals(i, (int) q.poll());
assertTrue(q.peek() == null ||
i != (int) q.peek());
}
assertNull(q.peek());
checkEmpty(q);
}
/**
* element returns next element, or throws NoSuchElementException if empty
*/
public void testElement() throws InterruptedException {
LinkedTransferQueue<Integer> q = populatedQueue(SIZE);
for (int i = 0; i < SIZE; ++i) {
assertEquals(i, (int) q.element());
assertEquals(i, (int) q.poll());
}
try {
q.element();
shouldThrow();
} catch (NoSuchElementException success) {}
checkEmpty(q);
}
/**
* remove removes next element, or throws NoSuchElementException if empty
*/
public void testRemove() throws InterruptedException {
LinkedTransferQueue<Integer> q = populatedQueue(SIZE);
for (int i = 0; i < SIZE; ++i) {
assertEquals(i, (int) q.remove());
}
try {
q.remove();
shouldThrow();
} catch (NoSuchElementException success) {}
checkEmpty(q);
}
/**
* An add following remove(x) succeeds
*/
public void testRemoveElementAndAdd() throws InterruptedException {
LinkedTransferQueue q = new LinkedTransferQueue();
assertTrue(q.add(one));
assertTrue(q.add(two));
assertTrue(q.remove(one));
assertTrue(q.remove(two));
assertTrue(q.add(three));
assertSame(q.take(), three);
}
/**
* contains(x) reports true when elements added but not yet removed
*/
public void testContains() {
LinkedTransferQueue<Integer> q = populatedQueue(SIZE);
for (int i = 0; i < SIZE; ++i) {
assertTrue(q.contains(i));
assertEquals(i, (int) q.poll());
assertFalse(q.contains(i));
}
}
/**
* clear removes all elements
*/
public void testClear() throws InterruptedException {
LinkedTransferQueue q = populatedQueue(SIZE);
q.clear();
checkEmpty(q);
assertEquals(Integer.MAX_VALUE, q.remainingCapacity());
q.add(one);
assertFalse(q.isEmpty());
assertEquals(1, q.size());
assertTrue(q.contains(one));
q.clear();
checkEmpty(q);
}
/**
* containsAll(c) is true when c contains a subset of elements
*/
public void testContainsAll() {
LinkedTransferQueue<Integer> q = populatedQueue(SIZE);
LinkedTransferQueue<Integer> p = new LinkedTransferQueue<Integer>();
for (int i = 0; i < SIZE; ++i) {
assertTrue(q.containsAll(p));
assertFalse(p.containsAll(q));
p.add(i);
}
assertTrue(p.containsAll(q));
}
/**
* retainAll(c) retains only those elements of c and reports true
* if changed
*/
public void testRetainAll() {
LinkedTransferQueue q = populatedQueue(SIZE);
LinkedTransferQueue p = populatedQueue(SIZE);
for (int i = 0; i < SIZE; ++i) {
boolean changed = q.retainAll(p);
if (i == 0) {
assertFalse(changed);
} else {
assertTrue(changed);
}
assertTrue(q.containsAll(p));
assertEquals(SIZE - i, q.size());
p.remove();
}
}
/**
* removeAll(c) removes only those elements of c and reports true
* if changed
*/
public void testRemoveAll() {
for (int i = 1; i < SIZE; ++i) {
LinkedTransferQueue q = populatedQueue(SIZE);
LinkedTransferQueue p = populatedQueue(i);
assertTrue(q.removeAll(p));
assertEquals(SIZE - i, q.size());
for (int j = 0; j < i; ++j) {
assertFalse(q.contains(p.remove()));
}
}
}
/**
* toArray() contains all elements in FIFO order
*/
public void testToArray() {
LinkedTransferQueue q = populatedQueue(SIZE);
Object[] o = q.toArray();
for (int i = 0; i < o.length; i++) {
assertSame(o[i], q.poll());
}
}
/**
* toArray(a) contains all elements in FIFO order
*/
public void testToArray2() {
LinkedTransferQueue<Integer> q = populatedQueue(SIZE);
Integer[] ints = new Integer[SIZE];
Integer[] array = q.toArray(ints);
assertSame(ints, array);
for (int i = 0; i < ints.length; i++) {
assertSame(ints[i], q.poll());
}
}
/**
* toArray(incompatible array type) throws ArrayStoreException
*/
public void testToArray1_BadArg() {
LinkedTransferQueue q = populatedQueue(SIZE);
try {
q.toArray(new String[10]);
shouldThrow();
} catch (ArrayStoreException success) {}
}
/**
* iterator iterates through all elements
*/
public void testIterator() throws InterruptedException {
LinkedTransferQueue q = populatedQueue(SIZE);
Iterator it = q.iterator();
int i;
for (i = 0; it.hasNext(); i++)
assertTrue(q.contains(it.next()));
assertEquals(i, SIZE);
assertIteratorExhausted(it);
it = q.iterator();
for (i = 0; it.hasNext(); i++)
assertEquals(it.next(), q.take());
assertEquals(i, SIZE);
assertIteratorExhausted(it);
}
/**
* iterator of empty collection has no elements
*/
public void testEmptyIterator() {
assertIteratorExhausted(new LinkedTransferQueue().iterator());
}
/**
* iterator.remove() removes current element
*/
public void testIteratorRemove() {
final LinkedTransferQueue q = new LinkedTransferQueue();
q.add(two);
q.add(one);
q.add(three);
Iterator it = q.iterator();
it.next();
it.remove();
it = q.iterator();
assertSame(it.next(), one);
assertSame(it.next(), three);
assertFalse(it.hasNext());
}
/**
* iterator ordering is FIFO
*/
public void testIteratorOrdering() {
final LinkedTransferQueue<Integer> q
= new LinkedTransferQueue<Integer>();
assertEquals(Integer.MAX_VALUE, q.remainingCapacity());
q.add(one);
q.add(two);
q.add(three);
assertEquals(Integer.MAX_VALUE, q.remainingCapacity());
int k = 0;
for (Integer n : q) {
assertEquals(++k, (int) n);
}
assertEquals(3, k);
}
/**
* Modifications do not cause iterators to fail
*/
public void testWeaklyConsistentIteration() {
final LinkedTransferQueue q = new LinkedTransferQueue();
q.add(one);
q.add(two);
q.add(three);
for (Iterator it = q.iterator(); it.hasNext();) {
q.remove();
it.next();
}
assertEquals(0, q.size());
}
/**
* toString contains toStrings of elements
*/
public void testToString() {
LinkedTransferQueue q = populatedQueue(SIZE);
String s = q.toString();
for (int i = 0; i < SIZE; ++i) {
assertTrue(s.contains(String.valueOf(i)));
}
}
/**
* offer transfers elements across Executor tasks
*/
public void testOfferInExecutor() {
final LinkedTransferQueue q = new LinkedTransferQueue();
final CheckedBarrier threadsStarted = new CheckedBarrier(2);
final ExecutorService executor = Executors.newFixedThreadPool(2);
try (PoolCleaner cleaner = cleaner(executor)) {
executor.execute(new CheckedRunnable() {
public void realRun() throws InterruptedException {
threadsStarted.await();
long startTime = System.nanoTime();
assertTrue(q.offer(one, LONG_DELAY_MS, MILLISECONDS));
assertTrue(millisElapsedSince(startTime) < LONG_DELAY_MS);
}});
executor.execute(new CheckedRunnable() {
public void realRun() throws InterruptedException {
threadsStarted.await();
assertSame(one, q.take());
checkEmpty(q);
}});
}
}
/**
* timed poll retrieves elements across Executor threads
*/
public void testPollInExecutor() {
final LinkedTransferQueue q = new LinkedTransferQueue();
final CheckedBarrier threadsStarted = new CheckedBarrier(2);
final ExecutorService executor = Executors.newFixedThreadPool(2);
try (PoolCleaner cleaner = cleaner(executor)) {
executor.execute(new CheckedRunnable() {
public void realRun() throws InterruptedException {
assertNull(q.poll());
threadsStarted.await();
long startTime = System.nanoTime();
assertSame(one, q.poll(LONG_DELAY_MS, MILLISECONDS));
assertTrue(millisElapsedSince(startTime) < LONG_DELAY_MS);
checkEmpty(q);
}});
executor.execute(new CheckedRunnable() {
public void realRun() throws InterruptedException {
threadsStarted.await();
q.put(one);
}});
}
}
/**
* A deserialized serialized queue has same elements in same order
*/
public void testSerialization() throws Exception {
Queue x = populatedQueue(SIZE);
Queue y = serialClone(x);
assertNotSame(y, x);
assertEquals(x.size(), y.size());
assertEquals(x.toString(), y.toString());
assertTrue(Arrays.equals(x.toArray(), y.toArray()));
while (!x.isEmpty()) {
assertFalse(y.isEmpty());
assertEquals(x.remove(), y.remove());
}
assertTrue(y.isEmpty());
}
/**
* drainTo(c) empties queue into another collection c
*/
public void testDrainTo() {
LinkedTransferQueue q = populatedQueue(SIZE);
ArrayList l = new ArrayList();
q.drainTo(l);
assertEquals(0, q.size());
assertEquals(SIZE, l.size());
for (int i = 0; i < SIZE; ++i) {
assertEquals(i, l.get(i));
}
q.add(zero);
q.add(one);
assertFalse(q.isEmpty());
assertTrue(q.contains(zero));
assertTrue(q.contains(one));
l.clear();
q.drainTo(l);
assertEquals(0, q.size());
assertEquals(2, l.size());
for (int i = 0; i < 2; ++i) {
assertEquals(i, l.get(i));
}
}
/**
* drainTo(c) empties full queue, unblocking a waiting put.
*/
public void testDrainToWithActivePut() throws InterruptedException {
final LinkedTransferQueue q = populatedQueue(SIZE);
Thread t = newStartedThread(new CheckedRunnable() {
public void realRun() {
q.put(SIZE + 1);
}});
ArrayList l = new ArrayList();
q.drainTo(l);
assertTrue(l.size() >= SIZE);
for (int i = 0; i < SIZE; ++i)
assertEquals(i, l.get(i));
awaitTermination(t);
assertTrue(q.size() + l.size() >= SIZE);
}
/**
* drainTo(c, n) empties first min(n, size) elements of queue into c
*/
public void testDrainToN() {
LinkedTransferQueue q = new LinkedTransferQueue();
for (int i = 0; i < SIZE + 2; ++i) {
for (int j = 0; j < SIZE; j++) {
assertTrue(q.offer(j));
}
ArrayList l = new ArrayList();
q.drainTo(l, i);
int k = (i < SIZE) ? i : SIZE;
assertEquals(k, l.size());
assertEquals(SIZE - k, q.size());
for (int j = 0; j < k; ++j)
assertEquals(j, l.get(j));
do {} while (q.poll() != null);
}
}
/**
* timed poll() or take() increments the waiting consumer count;
* offer(e) decrements the waiting consumer count
*/
public void testWaitingConsumer() throws InterruptedException {
final LinkedTransferQueue q = new LinkedTransferQueue();
assertEquals(0, q.getWaitingConsumerCount());
assertFalse(q.hasWaitingConsumer());
final CountDownLatch threadStarted = new CountDownLatch(1);
Thread t = newStartedThread(new CheckedRunnable() {
public void realRun() throws InterruptedException {
threadStarted.countDown();
long startTime = System.nanoTime();
assertSame(one, q.poll(LONG_DELAY_MS, MILLISECONDS));
assertEquals(0, q.getWaitingConsumerCount());
assertFalse(q.hasWaitingConsumer());
assertTrue(millisElapsedSince(startTime) < LONG_DELAY_MS);
}});
threadStarted.await();
waitForThreadToEnterWaitState(t);
assertEquals(1, q.getWaitingConsumerCount());
assertTrue(q.hasWaitingConsumer());
assertTrue(q.offer(one));
assertEquals(0, q.getWaitingConsumerCount());
assertFalse(q.hasWaitingConsumer());
awaitTermination(t);
}
/**
* transfer(null) throws NullPointerException
*/
public void testTransfer1() throws InterruptedException {
try {
LinkedTransferQueue q = new LinkedTransferQueue();
q.transfer(null);
shouldThrow();
} catch (NullPointerException success) {}
}
/**
* transfer waits until a poll occurs. The transfered element
* is returned by this associated poll.
*/
public void testTransfer2() throws InterruptedException {
final LinkedTransferQueue<Integer> q
= new LinkedTransferQueue<Integer>();
final CountDownLatch threadStarted = new CountDownLatch(1);
Thread t = newStartedThread(new CheckedRunnable() {
public void realRun() throws InterruptedException {
threadStarted.countDown();
q.transfer(five);
checkEmpty(q);
}});
threadStarted.await();
waitForThreadToEnterWaitState(t);
assertEquals(1, q.size());
assertSame(five, q.poll());
checkEmpty(q);
awaitTermination(t);
}
/**
* transfer waits until a poll occurs, and then transfers in fifo order
*/
public void testTransfer3() throws InterruptedException {
final LinkedTransferQueue<Integer> q
= new LinkedTransferQueue<Integer>();
Thread first = newStartedThread(new CheckedRunnable() {
public void realRun() throws InterruptedException {
q.transfer(four);
assertTrue(!q.contains(four));
assertEquals(1, q.size());
}});
Thread interruptedThread = newStartedThread(
new CheckedInterruptedRunnable() {
public void realRun() throws InterruptedException {
while (q.isEmpty())
Thread.yield();
q.transfer(five);
}});
while (q.size() < 2)
Thread.yield();
assertEquals(2, q.size());
assertSame(four, q.poll());
first.join();
assertEquals(1, q.size());
interruptedThread.interrupt();
interruptedThread.join();
checkEmpty(q);
}
/**
* transfer waits until a poll occurs, at which point the polling
* thread returns the element
*/
public void testTransfer4() throws InterruptedException {
final LinkedTransferQueue q = new LinkedTransferQueue();
Thread t = newStartedThread(new CheckedRunnable() {
public void realRun() throws InterruptedException {
q.transfer(four);
assertFalse(q.contains(four));
assertSame(three, q.poll());
}});
while (q.isEmpty())
Thread.yield();
assertFalse(q.isEmpty());
assertEquals(1, q.size());
assertTrue(q.offer(three));
assertSame(four, q.poll());
awaitTermination(t);
}
/**
* transfer waits until a take occurs. The transfered element
* is returned by this associated take.
*/
public void testTransfer5() throws InterruptedException {
final LinkedTransferQueue<Integer> q
= new LinkedTransferQueue<Integer>();
Thread t = newStartedThread(new CheckedRunnable() {
public void realRun() throws InterruptedException {
q.transfer(four);
checkEmpty(q);
}});
while (q.isEmpty())
Thread.yield();
assertFalse(q.isEmpty());
assertEquals(1, q.size());
assertSame(four, q.take());
checkEmpty(q);
awaitTermination(t);
}
/**
* tryTransfer(null) throws NullPointerException
*/
public void testTryTransfer1() {
final LinkedTransferQueue q = new LinkedTransferQueue();
try {
q.tryTransfer(null);
shouldThrow();
} catch (NullPointerException success) {}
}
/**
* tryTransfer returns false and does not enqueue if there are no
* consumers waiting to poll or take.
*/
public void testTryTransfer2() throws InterruptedException {
final LinkedTransferQueue q = new LinkedTransferQueue();
assertFalse(q.tryTransfer(new Object()));
assertFalse(q.hasWaitingConsumer());
checkEmpty(q);
}
/**
* If there is a consumer waiting in timed poll, tryTransfer
* returns true while successfully transfering object.
*/
public void testTryTransfer3() throws InterruptedException {
final Object hotPotato = new Object();
final LinkedTransferQueue q = new LinkedTransferQueue();
Thread t = newStartedThread(new CheckedRunnable() {
public void realRun() {
while (! q.hasWaitingConsumer())
Thread.yield();
assertTrue(q.hasWaitingConsumer());
checkEmpty(q);
assertTrue(q.tryTransfer(hotPotato));
}});
long startTime = System.nanoTime();
assertSame(hotPotato, q.poll(LONG_DELAY_MS, MILLISECONDS));
assertTrue(millisElapsedSince(startTime) < LONG_DELAY_MS);
checkEmpty(q);
awaitTermination(t);
}
/**
* If there is a consumer waiting in take, tryTransfer returns
* true while successfully transfering object.
*/
public void testTryTransfer4() throws InterruptedException {
final Object hotPotato = new Object();
final LinkedTransferQueue q = new LinkedTransferQueue();
Thread t = newStartedThread(new CheckedRunnable() {
public void realRun() {
while (! q.hasWaitingConsumer())
Thread.yield();
assertTrue(q.hasWaitingConsumer());
checkEmpty(q);
assertTrue(q.tryTransfer(hotPotato));
}});
assertSame(q.take(), hotPotato);
checkEmpty(q);
awaitTermination(t);
}
/**
* tryTransfer blocks interruptibly if no takers
*/
public void testTryTransfer5() throws InterruptedException {
final LinkedTransferQueue q = new LinkedTransferQueue();
final CountDownLatch pleaseInterrupt = new CountDownLatch(1);
assertTrue(q.isEmpty());
Thread t = newStartedThread(new CheckedRunnable() {
public void realRun() throws InterruptedException {
long startTime = System.nanoTime();
Thread.currentThread().interrupt();
try {
q.tryTransfer(new Object(), LONG_DELAY_MS, MILLISECONDS);
shouldThrow();
} catch (InterruptedException success) {}
assertFalse(Thread.interrupted());
pleaseInterrupt.countDown();
try {
q.tryTransfer(new Object(), LONG_DELAY_MS, MILLISECONDS);
shouldThrow();
} catch (InterruptedException success) {}
assertFalse(Thread.interrupted());
assertTrue(millisElapsedSince(startTime) < LONG_DELAY_MS);
}});
await(pleaseInterrupt);
assertThreadStaysAlive(t);
t.interrupt();
awaitTermination(t);
checkEmpty(q);
}
/**
* tryTransfer gives up after the timeout and returns false
*/
public void testTryTransfer6() throws InterruptedException {
final LinkedTransferQueue q = new LinkedTransferQueue();
Thread t = newStartedThread(new CheckedRunnable() {
public void realRun() throws InterruptedException {
long startTime = System.nanoTime();
assertFalse(q.tryTransfer(new Object(),
timeoutMillis(), MILLISECONDS));
assertTrue(millisElapsedSince(startTime) >= timeoutMillis());
checkEmpty(q);
}});
awaitTermination(t);
checkEmpty(q);
}
/**
* tryTransfer waits for any elements previously in to be removed
* before transfering to a poll or take
*/
public void testTryTransfer7() throws InterruptedException {
final LinkedTransferQueue q = new LinkedTransferQueue();
assertTrue(q.offer(four));
Thread t = newStartedThread(new CheckedRunnable() {
public void realRun() throws InterruptedException {
long startTime = System.nanoTime();
assertTrue(q.tryTransfer(five, LONG_DELAY_MS, MILLISECONDS));
assertTrue(millisElapsedSince(startTime) < LONG_DELAY_MS);
checkEmpty(q);
}});
while (q.size() != 2)
Thread.yield();
assertEquals(2, q.size());
assertSame(four, q.poll());
assertSame(five, q.poll());
checkEmpty(q);
awaitTermination(t);
}
/**
* tryTransfer attempts to enqueue into the queue and fails
* returning false not enqueueing and the successive poll is null
*/
public void testTryTransfer8() throws InterruptedException {
final LinkedTransferQueue q = new LinkedTransferQueue();
assertTrue(q.offer(four));
assertEquals(1, q.size());
long startTime = System.nanoTime();
assertFalse(q.tryTransfer(five, timeoutMillis(), MILLISECONDS));
assertTrue(millisElapsedSince(startTime) >= timeoutMillis());
assertEquals(1, q.size());
assertSame(four, q.poll());
assertNull(q.poll());
checkEmpty(q);
}
private LinkedTransferQueue<Integer> populatedQueue(int n) {
LinkedTransferQueue<Integer> q = new LinkedTransferQueue<Integer>();
checkEmpty(q);
for (int i = 0; i < n; i++) {
assertEquals(i, q.size());
assertTrue(q.offer(i));
assertEquals(Integer.MAX_VALUE, q.remainingCapacity());
}
assertFalse(q.isEmpty());
return q;
}
/**
* remove(null), contains(null) always return false
*/
public void testNeverContainsNull() {
Collection<?>[] qs = {
new LinkedTransferQueue<Object>(),
populatedQueue(2),
};
for (Collection<?> q : qs) {
assertFalse(q.contains(null));
assertFalse(q.remove(null));
}
}
}