test/tck/DelayQueueTest.java

/*
 * Written by Doug Lea with assistance from members of JCP JSR-166
 * Expert Group and released to the public domain, as explained at
 * http://creativecommons.org/publicdomain/zero/1.0/
 * Other contributors include Andrew Wright, Jeffrey Hayes,
 * Pat Fisher, Mike Judd.
 */

import static java.util.concurrent.TimeUnit.MILLISECONDS;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Iterator;
import java.util.NoSuchElementException;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.Delayed;
import java.util.concurrent.DelayQueue;
import java.util.concurrent.Executors;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.TimeUnit;

import junit.framework.Test;

public class DelayQueueTest extends JSR166TestCase {

    public static class Generic extends BlockingQueueTest {
        protected BlockingQueue emptyCollection() {
            return new DelayQueue();
        }
        protected PDelay makeElement(int i) {
            return new PDelay(i);
        }
    }

    public static void main(String[] args) {
        junit.textui.TestRunner.run(suite());
    }

    public static Test suite() {
        return newTestSuite(DelayQueueTest.class,
                            new Generic().testSuite());
    }

    private static final int NOCAP = Integer.MAX_VALUE;

    /**
     * A delayed implementation for testing.
     * Most tests use Pseudodelays, where delays are all elapsed
     * (so, no blocking solely for delays) but are still ordered
     */
    static class PDelay implements Delayed {
        int pseudodelay;
        PDelay(int i) { pseudodelay = i; }
        public int compareTo(PDelay other) {
            int a = this.pseudodelay;
            int b = other.pseudodelay;
            return (a < b) ? -1 : (a > b) ? 1 : 0;
        }
        public int compareTo(Delayed y) {
            return compareTo((PDelay)y);
        }
        public boolean equals(Object other) {
            return (other instanceof PDelay) &&
                this.pseudodelay == ((PDelay)other).pseudodelay;
        }
        // suppress [overrides] javac warning
        public int hashCode() { return pseudodelay; }
        public long getDelay(TimeUnit ignore) {
            return Integer.MIN_VALUE + pseudodelay;
        }
        public String toString() {
            return String.valueOf(pseudodelay);
        }
    }

    /**
     * Delayed implementation that actually delays
     */
    static class NanoDelay implements Delayed {
        long trigger;
        NanoDelay(long i) {
            trigger = System.nanoTime() + i;
        }
        public int compareTo(NanoDelay y) {
            long i = trigger;
            long j = y.trigger;
            if (i < j) return -1;
            if (i > j) return 1;
            return 0;
        }

        public int compareTo(Delayed y) {
            return compareTo((NanoDelay)y);
        }

        public boolean equals(Object other) {
            return equals((NanoDelay)other);
        }
        public boolean equals(NanoDelay other) {
            return other.trigger == trigger;
        }

        // suppress [overrides] javac warning
        public int hashCode() { return (int) trigger; }

        public long getDelay(TimeUnit unit) {
            long n = trigger - System.nanoTime();
            return unit.convert(n, TimeUnit.NANOSECONDS);
        }

        public long getTriggerTime() {
            return trigger;
        }

        public String toString() {
            return String.valueOf(trigger);
        }
    }

    /**
     * Returns a new queue of given size containing consecutive
     * PDelays 0 ... n.
     */
    private DelayQueue<PDelay> populatedQueue(int n) {
        DelayQueue<PDelay> q = new DelayQueue<PDelay>();
        assertTrue(q.isEmpty());
        for (int i = n-1; i >= 0; i -= 2)
            assertTrue(q.offer(new PDelay(i)));
        for (int i = (n & 1); i < n; i += 2)
            assertTrue(q.offer(new PDelay(i)));
        assertFalse(q.isEmpty());
        assertEquals(NOCAP, q.remainingCapacity());
        assertEquals(n, q.size());
        return q;
    }

    /**
     * A new queue has unbounded capacity
     */
    public void testConstructor1() {
        assertEquals(NOCAP, new DelayQueue().remainingCapacity());
    }

    /**
     * Initializing from null Collection throws NPE
     */
    public void testConstructor3() {
        try {
            new DelayQueue(null);
            shouldThrow();
        } catch (NullPointerException success) {}
    }

    /**
     * Initializing from Collection of null elements throws NPE
     */
    public void testConstructor4() {
        try {
            PDelay[] ints = new PDelay[SIZE];
            new DelayQueue(Arrays.asList(ints));
            shouldThrow();
        } catch (NullPointerException success) {}
    }

    /**
     * Initializing from Collection with some null elements throws NPE
     */
    public void testConstructor5() {
        try {
            PDelay[] ints = new PDelay[SIZE];
            for (int i = 0; i < SIZE-1; ++i)
                ints[i] = new PDelay(i);
            new DelayQueue(Arrays.asList(ints));
            shouldThrow();
        } catch (NullPointerException success) {}
    }

    /**
     * Queue contains all elements of collection used to initialize
     */
    public void testConstructor6() {
        PDelay[] ints = new PDelay[SIZE];
        for (int i = 0; i < SIZE; ++i)
            ints[i] = new PDelay(i);
        DelayQueue q = new DelayQueue(Arrays.asList(ints));
        for (int i = 0; i < SIZE; ++i)
            assertEquals(ints[i], q.poll());
    }

    /**
     * isEmpty is true before add, false after
     */
    public void testEmpty() {
        DelayQueue q = new DelayQueue();
        assertTrue(q.isEmpty());
        assertEquals(NOCAP, q.remainingCapacity());
        q.add(new PDelay(1));
        assertFalse(q.isEmpty());
        q.add(new PDelay(2));
        q.remove();
        q.remove();
        assertTrue(q.isEmpty());
    }

    /**
     * remainingCapacity does not change when elements added or removed,
     * but size does
     */
    public void testRemainingCapacity() {
        DelayQueue q = populatedQueue(SIZE);
        for (int i = 0; i < SIZE; ++i) {
            assertEquals(NOCAP, q.remainingCapacity());
            assertEquals(SIZE-i, q.size());
            q.remove();
        }
        for (int i = 0; i < SIZE; ++i) {
            assertEquals(NOCAP, q.remainingCapacity());
            assertEquals(i, q.size());
            q.add(new PDelay(i));
        }
    }

    /**
     * offer non-null succeeds
     */
    public void testOffer() {
        DelayQueue q = new DelayQueue();
        assertTrue(q.offer(new PDelay(0)));
        assertTrue(q.offer(new PDelay(1)));
    }

    /**
     * add succeeds
     */
    public void testAdd() {
        DelayQueue q = new DelayQueue();
        for (int i = 0; i < SIZE; ++i) {
            assertEquals(i, q.size());
            assertTrue(q.add(new PDelay(i)));
        }
    }

    /**
     * addAll(this) throws IAE
     */
    public void testAddAllSelf() {
        try {
            DelayQueue q = populatedQueue(SIZE);
            q.addAll(q);
            shouldThrow();
        } catch (IllegalArgumentException success) {}
    }

    /**
     * addAll of a collection with any null elements throws NPE after
     * possibly adding some elements
     */
    public void testAddAll3() {
        try {
            DelayQueue q = new DelayQueue();
            PDelay[] ints = new PDelay[SIZE];
            for (int i = 0; i < SIZE-1; ++i)
                ints[i] = new PDelay(i);
            q.addAll(Arrays.asList(ints));
            shouldThrow();
        } catch (NullPointerException success) {}
    }

    /**
     * Queue contains all elements of successful addAll
     */
    public void testAddAll5() {
        PDelay[] empty = new PDelay[0];
        PDelay[] ints = new PDelay[SIZE];
        for (int i = SIZE-1; i >= 0; --i)
            ints[i] = new PDelay(i);
        DelayQueue q = new DelayQueue();
        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() {
        DelayQueue q = new DelayQueue();
        for (int i = 0; i < SIZE; ++i) {
            PDelay x = new PDelay(i);
            q.put(x);
            assertTrue(q.contains(x));
        }
        assertEquals(SIZE, q.size());
    }

    /**
     * put doesn't block waiting for take
     */
    public void testPutWithTake() throws InterruptedException {
        final DelayQueue q = new DelayQueue();
        Thread t = newStartedThread(new CheckedRunnable() {
            public void realRun() {
                q.put(new PDelay(0));
                q.put(new PDelay(0));
                q.put(new PDelay(0));
                q.put(new PDelay(0));
            }});

        awaitTermination(t);
        assertEquals(4, q.size());
    }

    /**
     * timed offer does not time out
     */
    public void testTimedOffer() throws InterruptedException {
        final DelayQueue q = new DelayQueue();
        Thread t = newStartedThread(new CheckedRunnable() {
            public void realRun() throws InterruptedException {
                q.put(new PDelay(0));
                q.put(new PDelay(0));
                assertTrue(q.offer(new PDelay(0), SHORT_DELAY_MS, MILLISECONDS));
                assertTrue(q.offer(new PDelay(0), LONG_DELAY_MS, MILLISECONDS));
            }});

        awaitTermination(t);
    }

    /**
     * take retrieves elements in priority order
     */
    public void testTake() throws InterruptedException {
        DelayQueue q = populatedQueue(SIZE);
        for (int i = 0; i < SIZE; ++i) {
            assertEquals(new PDelay(i), q.take());
        }
    }

    /**
     * Take removes existing elements until empty, then blocks interruptibly
     */
    public void testBlockingTake() throws InterruptedException {
        final DelayQueue 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(new PDelay(i), ((PDelay)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() {
        DelayQueue q = populatedQueue(SIZE);
        for (int i = 0; i < SIZE; ++i) {
            assertEquals(new PDelay(i), q.poll());
        }
        assertNull(q.poll());
    }

    /**
     * timed poll with zero timeout succeeds when non-empty, else times out
     */
    public void testTimedPoll0() throws InterruptedException {
        DelayQueue q = populatedQueue(SIZE);
        for (int i = 0; i < SIZE; ++i) {
            assertEquals(new PDelay(i), q.poll(0, MILLISECONDS));
        }
        assertNull(q.poll(0, MILLISECONDS));
    }

    /**
     * timed poll with nonzero timeout succeeds when non-empty, else times out
     */
    public void testTimedPoll() throws InterruptedException {
        DelayQueue q = populatedQueue(SIZE);
        for (int i = 0; i < SIZE; ++i) {
            long startTime = System.nanoTime();
            assertEquals(new PDelay(i), q.poll(LONG_DELAY_MS, MILLISECONDS));
            assertTrue(millisElapsedSince(startTime) < LONG_DELAY_MS);
        }
        long 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 CountDownLatch pleaseInterrupt = new CountDownLatch(1);
        Thread t = newStartedThread(new CheckedRunnable() {
            public void realRun() throws InterruptedException {
                DelayQueue q = populatedQueue(SIZE);
                for (int i = 0; i < SIZE; ++i) {
                    assertEquals(new PDelay(i), ((PDelay)q.poll(SHORT_DELAY_MS, MILLISECONDS)));
                }

                Thread.currentThread().interrupt();
                try {
                    q.poll(LONG_DELAY_MS, MILLISECONDS);
                    shouldThrow();
                } catch (InterruptedException success) {}
                assertFalse(Thread.interrupted());

                pleaseInterrupt.countDown();
                try {
                    q.poll(LONG_DELAY_MS, MILLISECONDS);
                    shouldThrow();
                } catch (InterruptedException success) {}
                assertFalse(Thread.interrupted());
            }});

        await(pleaseInterrupt);
        assertThreadStaysAlive(t);
        t.interrupt();
        awaitTermination(t);
    }

    /**
     * peek returns next element, or null if empty
     */
    public void testPeek() {
        DelayQueue q = populatedQueue(SIZE);
        for (int i = 0; i < SIZE; ++i) {
            assertEquals(new PDelay(i), q.peek());
            assertEquals(new PDelay(i), q.poll());
            if (q.isEmpty())
                assertNull(q.peek());
            else
                assertFalse(new PDelay(i).equals(q.peek()));
        }
        assertNull(q.peek());
    }

    /**
     * element returns next element, or throws NSEE if empty
     */
    public void testElement() {
        DelayQueue q = populatedQueue(SIZE);
        for (int i = 0; i < SIZE; ++i) {
            assertEquals(new PDelay(i), q.element());
            q.poll();
        }
        try {
            q.element();
            shouldThrow();
        } catch (NoSuchElementException success) {}
    }

    /**
     * remove removes next element, or throws NSEE if empty
     */
    public void testRemove() {
        DelayQueue q = populatedQueue(SIZE);
        for (int i = 0; i < SIZE; ++i) {
            assertEquals(new PDelay(i), q.remove());
        }
        try {
            q.remove();
            shouldThrow();
        } catch (NoSuchElementException success) {}
    }

    /**
     * contains(x) reports true when elements added but not yet removed
     */
    public void testContains() {
        DelayQueue q = populatedQueue(SIZE);
        for (int i = 0; i < SIZE; ++i) {
            assertTrue(q.contains(new PDelay(i)));
            q.poll();
            assertFalse(q.contains(new PDelay(i)));
        }
    }

    /**
     * clear removes all elements
     */
    public void testClear() {
        DelayQueue q = populatedQueue(SIZE);
        q.clear();
        assertTrue(q.isEmpty());
        assertEquals(0, q.size());
        assertEquals(NOCAP, q.remainingCapacity());
        PDelay x = new PDelay(1);
        q.add(x);
        assertFalse(q.isEmpty());
        assertTrue(q.contains(x));
        q.clear();
        assertTrue(q.isEmpty());
    }

    /**
     * containsAll(c) is true when c contains a subset of elements
     */
    public void testContainsAll() {
        DelayQueue q = populatedQueue(SIZE);
        DelayQueue p = new DelayQueue();
        for (int i = 0; i < SIZE; ++i) {
            assertTrue(q.containsAll(p));
            assertFalse(p.containsAll(q));
            p.add(new PDelay(i));
        }
        assertTrue(p.containsAll(q));
    }

    /**
     * retainAll(c) retains only those elements of c and reports true if changed
     */
    public void testRetainAll() {
        DelayQueue q = populatedQueue(SIZE);
        DelayQueue 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) {
            DelayQueue q = populatedQueue(SIZE);
            DelayQueue p = populatedQueue(i);
            assertTrue(q.removeAll(p));
            assertEquals(SIZE-i, q.size());
            for (int j = 0; j < i; ++j) {
                PDelay x = (PDelay)(p.remove());
                assertFalse(q.contains(x));
            }
        }
    }

    /**
     * toArray contains all elements
     */
    public void testToArray() throws InterruptedException {
        DelayQueue q = populatedQueue(SIZE);
        Object[] o = q.toArray();
        Arrays.sort(o);
        for (int i = 0; i < o.length; i++)
            assertSame(o[i], q.take());
    }

    /**
     * toArray(a) contains all elements
     */
    public void testToArray2() {
        DelayQueue<PDelay> q = populatedQueue(SIZE);
        PDelay[] ints = new PDelay[SIZE];
        PDelay[] array = q.toArray(ints);
        assertSame(ints, array);
        Arrays.sort(ints);
        for (int i = 0; i < ints.length; i++)
            assertSame(ints[i], q.remove());
    }

    /**
     * toArray(incompatible array type) throws ArrayStoreException
     */
    public void testToArray1_BadArg() {
        DelayQueue q = populatedQueue(SIZE);
        try {
            q.toArray(new String[10]);
            shouldThrow();
        } catch (ArrayStoreException success) {}
    }

    /**
     * iterator iterates through all elements
     */
    public void testIterator() {
        DelayQueue q = populatedQueue(SIZE);
        int i = 0;
        Iterator it = q.iterator();
        while (it.hasNext()) {
            assertTrue(q.contains(it.next()));
            ++i;
        }
        assertEquals(i, SIZE);
        assertIteratorExhausted(it);
    }

    /**
     * iterator of empty collection has no elements
     */
    public void testEmptyIterator() {
        assertIteratorExhausted(new DelayQueue().iterator());
    }

    /**
     * iterator.remove removes current element
     */
    public void testIteratorRemove() {
        final DelayQueue q = new DelayQueue();
        q.add(new PDelay(2));
        q.add(new PDelay(1));
        q.add(new PDelay(3));
        Iterator it = q.iterator();
        it.next();
        it.remove();
        it = q.iterator();
        assertEquals(new PDelay(2), it.next());
        assertEquals(new PDelay(3), it.next());
        assertFalse(it.hasNext());
    }

    /**
     * toString contains toStrings of elements
     */
    public void testToString() {
        DelayQueue q = populatedQueue(SIZE);
        String s = q.toString();
        for (Object e : q)
            assertTrue(s.contains(e.toString()));
    }

    /**
     * timed poll transfers elements across Executor tasks
     */
    public void testPollInExecutor() {
        final DelayQueue q = new DelayQueue();
        final CheckedBarrier threadsStarted = new CheckedBarrier(2);
        ExecutorService executor = Executors.newFixedThreadPool(2);
        executor.execute(new CheckedRunnable() {
            public void realRun() throws InterruptedException {
                assertNull(q.poll());
                threadsStarted.await();
                assertNotNull(q.poll(LONG_DELAY_MS, MILLISECONDS));
                checkEmpty(q);
            }});

        executor.execute(new CheckedRunnable() {
            public void realRun() throws InterruptedException {
                threadsStarted.await();
                q.put(new PDelay(1));
            }});

        joinPool(executor);
    }

    /**
     * Delayed actions do not occur until their delay elapses
     */
    public void testDelay() throws InterruptedException {
        DelayQueue<NanoDelay> q = new DelayQueue<NanoDelay>();
        for (int i = 0; i < SIZE; ++i)
            q.add(new NanoDelay(1000000L * (SIZE - i)));

        long last = 0;
        for (int i = 0; i < SIZE; ++i) {
            NanoDelay e = q.take();
            long tt = e.getTriggerTime();
            assertTrue(System.nanoTime() - tt >= 0);
            if (i != 0)
                assertTrue(tt >= last);
            last = tt;
        }
        assertTrue(q.isEmpty());
    }

    /**
     * peek of a non-empty queue returns non-null even if not expired
     */
    public void testPeekDelayed() {
        DelayQueue q = new DelayQueue();
        q.add(new NanoDelay(Long.MAX_VALUE));
        assertNotNull(q.peek());
    }

    /**
     * poll of a non-empty queue returns null if no expired elements.
     */
    public void testPollDelayed() {
        DelayQueue q = new DelayQueue();
        q.add(new NanoDelay(Long.MAX_VALUE));
        assertNull(q.poll());
    }

    /**
     * timed poll of a non-empty queue returns null if no expired elements.
     */
    public void testTimedPollDelayed() throws InterruptedException {
        DelayQueue q = new DelayQueue();
        q.add(new NanoDelay(LONG_DELAY_MS * 1000000L));
        assertNull(q.poll(timeoutMillis(), MILLISECONDS));
    }

    /**
     * drainTo(c) empties queue into another collection c
     */
    public void testDrainTo() {
        DelayQueue q = new DelayQueue();
        PDelay[] elems = new PDelay[SIZE];
        for (int i = 0; i < SIZE; ++i) {
            elems[i] = new PDelay(i);
            q.add(elems[i]);
        }
        ArrayList l = new ArrayList();
        q.drainTo(l);
        assertEquals(0, q.size());
        for (int i = 0; i < SIZE; ++i)
            assertEquals(elems[i], l.get(i));
        q.add(elems[0]);
        q.add(elems[1]);
        assertFalse(q.isEmpty());
        assertTrue(q.contains(elems[0]));
        assertTrue(q.contains(elems[1]));
        l.clear();
        q.drainTo(l);
        assertEquals(0, q.size());
        assertEquals(2, l.size());
        for (int i = 0; i < 2; ++i)
            assertEquals(elems[i], l.get(i));
    }

    /**
     * drainTo empties queue
     */
    public void testDrainToWithActivePut() throws InterruptedException {
        final DelayQueue q = populatedQueue(SIZE);
        Thread t = new Thread(new CheckedRunnable() {
            public void realRun() {
                q.put(new PDelay(SIZE+1));
            }});

        t.start();
        ArrayList l = new ArrayList();
        q.drainTo(l);
        assertTrue(l.size() >= SIZE);
        t.join();
        assertTrue(q.size() + l.size() >= SIZE);
    }

    /**
     * drainTo(c, n) empties first min(n, size) elements of queue into c
     */
    public void testDrainToN() {
        for (int i = 0; i < SIZE + 2; ++i) {
            DelayQueue q = populatedQueue(SIZE);
            ArrayList l = new ArrayList();
            q.drainTo(l, i);
            int k = (i < SIZE) ? i : SIZE;
            assertEquals(SIZE-k, q.size());
            assertEquals(k, l.size());
        }
    }

    /**
     * remove(null), contains(null) always return false
     */
    public void testNeverContainsNull() {
        Collection<?> q = populatedQueue(SIZE);
        assertFalse(q.contains(null));
        assertFalse(q.remove(null));
    }
}
Revision:	1.69
Committed:	Sun Feb 22 04:34:44 2015 UTC (9 years, 2 months ago) by jsr166
Branch:	MAIN
Changes since 1.68:	+3 -3 lines
Log Message:	unused variable cleanup
#	Content
1	/*
2	* Written by Doug Lea with assistance from members of JCP JSR-166
3	* Expert Group and released to the public domain, as explained at
4	* http://creativecommons.org/publicdomain/zero/1.0/
5	* Other contributors include Andrew Wright, Jeffrey Hayes,
6	* Pat Fisher, Mike Judd.
7	*/
8
9	import static java.util.concurrent.TimeUnit.MILLISECONDS;
10
11	import java.util.ArrayList;
12	import java.util.Arrays;
13	import java.util.Collection;
14	import java.util.Iterator;
15	import java.util.NoSuchElementException;
16	import java.util.concurrent.BlockingQueue;
17	import java.util.concurrent.CountDownLatch;
18	import java.util.concurrent.Delayed;
19	import java.util.concurrent.DelayQueue;
20	import java.util.concurrent.Executors;
21	import java.util.concurrent.ExecutorService;
22	import java.util.concurrent.TimeUnit;
23
24	import junit.framework.Test;
25
26	public class DelayQueueTest extends JSR166TestCase {
27
28	public static class Generic extends BlockingQueueTest {
29	protected BlockingQueue emptyCollection() {
30	return new DelayQueue();
31	}
32	protected PDelay makeElement(int i) {
33	return new PDelay(i);
34	}
35	}
36
37	public static void main(String[] args) {
38	junit.textui.TestRunner.run(suite());
39	}
40
41	public static Test suite() {
42	return newTestSuite(DelayQueueTest.class,
43	new Generic().testSuite());
44	}
45
46	private static final int NOCAP = Integer.MAX_VALUE;
47
48	/**
49	* A delayed implementation for testing.
50	* Most tests use Pseudodelays, where delays are all elapsed
51	* (so, no blocking solely for delays) but are still ordered
52	*/
53	static class PDelay implements Delayed {
54	int pseudodelay;
55	PDelay(int i) { pseudodelay = i; }
56	public int compareTo(PDelay other) {
57	int a = this.pseudodelay;
58	int b = other.pseudodelay;
59	return (a < b) ? -1 : (a > b) ? 1 : 0;
60	}
61	public int compareTo(Delayed y) {
62	return compareTo((PDelay)y);
63	}
64	public boolean equals(Object other) {
65	return (other instanceof PDelay) &&
66	this.pseudodelay == ((PDelay)other).pseudodelay;
67	}
68	// suppress [overrides] javac warning
69	public int hashCode() { return pseudodelay; }
70	public long getDelay(TimeUnit ignore) {
71	return Integer.MIN_VALUE + pseudodelay;
72	}
73	public String toString() {
74	return String.valueOf(pseudodelay);
75	}
76	}
77
78	/**
79	* Delayed implementation that actually delays
80	*/
81	static class NanoDelay implements Delayed {
82	long trigger;
83	NanoDelay(long i) {
84	trigger = System.nanoTime() + i;
85	}
86	public int compareTo(NanoDelay y) {
87	long i = trigger;
88	long j = y.trigger;
89	if (i < j) return -1;
90	if (i > j) return 1;
91	return 0;
92	}
93
94	public int compareTo(Delayed y) {
95	return compareTo((NanoDelay)y);
96	}
97
98	public boolean equals(Object other) {
99	return equals((NanoDelay)other);
100	}
101	public boolean equals(NanoDelay other) {
102	return other.trigger == trigger;
103	}
104
105	// suppress [overrides] javac warning
106	public int hashCode() { return (int) trigger; }
107
108	public long getDelay(TimeUnit unit) {
109	long n = trigger - System.nanoTime();
110	return unit.convert(n, TimeUnit.NANOSECONDS);
111	}
112
113	public long getTriggerTime() {
114	return trigger;
115	}
116
117	public String toString() {
118	return String.valueOf(trigger);
119	}
120	}
121
122	/**
123	* Returns a new queue of given size containing consecutive
124	* PDelays 0 ... n.
125	*/
126	private DelayQueue<PDelay> populatedQueue(int n) {
127	DelayQueue<PDelay> q = new DelayQueue<PDelay>();
128	assertTrue(q.isEmpty());
129	for (int i = n-1; i >= 0; i -= 2)
130	assertTrue(q.offer(new PDelay(i)));
131	for (int i = (n & 1); i < n; i += 2)
132	assertTrue(q.offer(new PDelay(i)));
133	assertFalse(q.isEmpty());
134	assertEquals(NOCAP, q.remainingCapacity());
135	assertEquals(n, q.size());
136	return q;
137	}
138
139	/**
140	* A new queue has unbounded capacity
141	*/
142	public void testConstructor1() {
143	assertEquals(NOCAP, new DelayQueue().remainingCapacity());
144	}
145
146	/**
147	* Initializing from null Collection throws NPE
148	*/
149	public void testConstructor3() {
150	try {
151	new DelayQueue(null);
152	shouldThrow();
153	} catch (NullPointerException success) {}
154	}
155
156	/**
157	* Initializing from Collection of null elements throws NPE
158	*/
159	public void testConstructor4() {
160	try {
161	PDelay[] ints = new PDelay[SIZE];
162	new DelayQueue(Arrays.asList(ints));
163	shouldThrow();
164	} catch (NullPointerException success) {}
165	}
166
167	/**
168	* Initializing from Collection with some null elements throws NPE
169	*/
170	public void testConstructor5() {
171	try {
172	PDelay[] ints = new PDelay[SIZE];
173	for (int i = 0; i < SIZE-1; ++i)
174	ints[i] = new PDelay(i);
175	new DelayQueue(Arrays.asList(ints));
176	shouldThrow();
177	} catch (NullPointerException success) {}
178	}
179
180	/**
181	* Queue contains all elements of collection used to initialize
182	*/
183	public void testConstructor6() {
184	PDelay[] ints = new PDelay[SIZE];
185	for (int i = 0; i < SIZE; ++i)
186	ints[i] = new PDelay(i);
187	DelayQueue q = new DelayQueue(Arrays.asList(ints));
188	for (int i = 0; i < SIZE; ++i)
189	assertEquals(ints[i], q.poll());
190	}
191
192	/**
193	* isEmpty is true before add, false after
194	*/
195	public void testEmpty() {
196	DelayQueue q = new DelayQueue();
197	assertTrue(q.isEmpty());
198	assertEquals(NOCAP, q.remainingCapacity());
199	q.add(new PDelay(1));
200	assertFalse(q.isEmpty());
201	q.add(new PDelay(2));
202	q.remove();
203	q.remove();
204	assertTrue(q.isEmpty());
205	}
206
207	/**
208	* remainingCapacity does not change when elements added or removed,
209	* but size does
210	*/
211	public void testRemainingCapacity() {
212	DelayQueue q = populatedQueue(SIZE);
213	for (int i = 0; i < SIZE; ++i) {
214	assertEquals(NOCAP, q.remainingCapacity());
215	assertEquals(SIZE-i, q.size());
216	q.remove();
217	}
218	for (int i = 0; i < SIZE; ++i) {
219	assertEquals(NOCAP, q.remainingCapacity());
220	assertEquals(i, q.size());
221	q.add(new PDelay(i));
222	}
223	}
224
225	/**
226	* offer non-null succeeds
227	*/
228	public void testOffer() {
229	DelayQueue q = new DelayQueue();
230	assertTrue(q.offer(new PDelay(0)));
231	assertTrue(q.offer(new PDelay(1)));
232	}
233
234	/**
235	* add succeeds
236	*/
237	public void testAdd() {
238	DelayQueue q = new DelayQueue();
239	for (int i = 0; i < SIZE; ++i) {
240	assertEquals(i, q.size());
241	assertTrue(q.add(new PDelay(i)));
242	}
243	}
244
245	/**
246	* addAll(this) throws IAE
247	*/
248	public void testAddAllSelf() {
249	try {
250	DelayQueue q = populatedQueue(SIZE);
251	q.addAll(q);
252	shouldThrow();
253	} catch (IllegalArgumentException success) {}
254	}
255
256	/**
257	* addAll of a collection with any null elements throws NPE after
258	* possibly adding some elements
259	*/
260	public void testAddAll3() {
261	try {
262	DelayQueue q = new DelayQueue();
263	PDelay[] ints = new PDelay[SIZE];
264	for (int i = 0; i < SIZE-1; ++i)
265	ints[i] = new PDelay(i);
266	q.addAll(Arrays.asList(ints));
267	shouldThrow();
268	} catch (NullPointerException success) {}
269	}
270
271	/**
272	* Queue contains all elements of successful addAll
273	*/
274	public void testAddAll5() {
275	PDelay[] empty = new PDelay[0];
276	PDelay[] ints = new PDelay[SIZE];
277	for (int i = SIZE-1; i >= 0; --i)
278	ints[i] = new PDelay(i);
279	DelayQueue q = new DelayQueue();
280	assertFalse(q.addAll(Arrays.asList(empty)));
281	assertTrue(q.addAll(Arrays.asList(ints)));
282	for (int i = 0; i < SIZE; ++i)
283	assertEquals(ints[i], q.poll());
284	}
285
286	/**
287	* all elements successfully put are contained
288	*/
289	public void testPut() {
290	DelayQueue q = new DelayQueue();
291	for (int i = 0; i < SIZE; ++i) {
292	PDelay x = new PDelay(i);
293	q.put(x);
294	assertTrue(q.contains(x));
295	}
296	assertEquals(SIZE, q.size());
297	}
298
299	/**
300	* put doesn't block waiting for take
301	*/
302	public void testPutWithTake() throws InterruptedException {
303	final DelayQueue q = new DelayQueue();
304	Thread t = newStartedThread(new CheckedRunnable() {
305	public void realRun() {
306	q.put(new PDelay(0));
307	q.put(new PDelay(0));
308	q.put(new PDelay(0));
309	q.put(new PDelay(0));
310	}});
311
312	awaitTermination(t);
313	assertEquals(4, q.size());
314	}
315
316	/**
317	* timed offer does not time out
318	*/
319	public void testTimedOffer() throws InterruptedException {
320	final DelayQueue q = new DelayQueue();
321	Thread t = newStartedThread(new CheckedRunnable() {
322	public void realRun() throws InterruptedException {
323	q.put(new PDelay(0));
324	q.put(new PDelay(0));
325	assertTrue(q.offer(new PDelay(0), SHORT_DELAY_MS, MILLISECONDS));
326	assertTrue(q.offer(new PDelay(0), LONG_DELAY_MS, MILLISECONDS));
327	}});
328
329	awaitTermination(t);
330	}
331
332	/**
333	* take retrieves elements in priority order
334	*/
335	public void testTake() throws InterruptedException {
336	DelayQueue q = populatedQueue(SIZE);
337	for (int i = 0; i < SIZE; ++i) {
338	assertEquals(new PDelay(i), q.take());
339	}
340	}
341
342	/**
343	* Take removes existing elements until empty, then blocks interruptibly
344	*/
345	public void testBlockingTake() throws InterruptedException {
346	final DelayQueue q = populatedQueue(SIZE);
347	final CountDownLatch pleaseInterrupt = new CountDownLatch(1);
348	Thread t = newStartedThread(new CheckedRunnable() {
349	public void realRun() throws InterruptedException {
350	for (int i = 0; i < SIZE; ++i) {
351	assertEquals(new PDelay(i), ((PDelay)q.take()));
352	}
353
354	Thread.currentThread().interrupt();
355	try {
356	q.take();
357	shouldThrow();
358	} catch (InterruptedException success) {}
359	assertFalse(Thread.interrupted());
360
361	pleaseInterrupt.countDown();
362	try {
363	q.take();
364	shouldThrow();
365	} catch (InterruptedException success) {}
366	assertFalse(Thread.interrupted());
367	}});
368
369	await(pleaseInterrupt);
370	assertThreadStaysAlive(t);
371	t.interrupt();
372	awaitTermination(t);
373	}
374
375	/**
376	* poll succeeds unless empty
377	*/
378	public void testPoll() {
379	DelayQueue q = populatedQueue(SIZE);
380	for (int i = 0; i < SIZE; ++i) {
381	assertEquals(new PDelay(i), q.poll());
382	}
383	assertNull(q.poll());
384	}
385
386	/**
387	* timed poll with zero timeout succeeds when non-empty, else times out
388	*/
389	public void testTimedPoll0() throws InterruptedException {
390	DelayQueue q = populatedQueue(SIZE);
391	for (int i = 0; i < SIZE; ++i) {
392	assertEquals(new PDelay(i), q.poll(0, MILLISECONDS));
393	}
394	assertNull(q.poll(0, MILLISECONDS));
395	}
396
397	/**
398	* timed poll with nonzero timeout succeeds when non-empty, else times out
399	*/
400	public void testTimedPoll() throws InterruptedException {
401	DelayQueue q = populatedQueue(SIZE);
402	for (int i = 0; i < SIZE; ++i) {
403	long startTime = System.nanoTime();
404	assertEquals(new PDelay(i), q.poll(LONG_DELAY_MS, MILLISECONDS));
405	assertTrue(millisElapsedSince(startTime) < LONG_DELAY_MS);
406	}
407	long startTime = System.nanoTime();
408	assertNull(q.poll(timeoutMillis(), MILLISECONDS));
409	assertTrue(millisElapsedSince(startTime) >= timeoutMillis());
410	checkEmpty(q);
411	}
412
413	/**
414	* Interrupted timed poll throws InterruptedException instead of
415	* returning timeout status
416	*/
417	public void testInterruptedTimedPoll() throws InterruptedException {
418	final CountDownLatch pleaseInterrupt = new CountDownLatch(1);
419	Thread t = newStartedThread(new CheckedRunnable() {
420	public void realRun() throws InterruptedException {
421	DelayQueue q = populatedQueue(SIZE);
422	for (int i = 0; i < SIZE; ++i) {
423	assertEquals(new PDelay(i), ((PDelay)q.poll(SHORT_DELAY_MS, MILLISECONDS)));
424	}
425
426	Thread.currentThread().interrupt();
427	try {
428	q.poll(LONG_DELAY_MS, MILLISECONDS);
429	shouldThrow();
430	} catch (InterruptedException success) {}
431	assertFalse(Thread.interrupted());
432
433	pleaseInterrupt.countDown();
434	try {
435	q.poll(LONG_DELAY_MS, MILLISECONDS);
436	shouldThrow();
437	} catch (InterruptedException success) {}
438	assertFalse(Thread.interrupted());
439	}});
440
441	await(pleaseInterrupt);
442	assertThreadStaysAlive(t);
443	t.interrupt();
444	awaitTermination(t);
445	}
446
447	/**
448	* peek returns next element, or null if empty
449	*/
450	public void testPeek() {
451	DelayQueue q = populatedQueue(SIZE);
452	for (int i = 0; i < SIZE; ++i) {
453	assertEquals(new PDelay(i), q.peek());
454	assertEquals(new PDelay(i), q.poll());
455	if (q.isEmpty())
456	assertNull(q.peek());
457	else
458	assertFalse(new PDelay(i).equals(q.peek()));
459	}
460	assertNull(q.peek());
461	}
462
463	/**
464	* element returns next element, or throws NSEE if empty
465	*/
466	public void testElement() {
467	DelayQueue q = populatedQueue(SIZE);
468	for (int i = 0; i < SIZE; ++i) {
469	assertEquals(new PDelay(i), q.element());
470	q.poll();
471	}
472	try {
473	q.element();
474	shouldThrow();
475	} catch (NoSuchElementException success) {}
476	}
477
478	/**
479	* remove removes next element, or throws NSEE if empty
480	*/
481	public void testRemove() {
482	DelayQueue q = populatedQueue(SIZE);
483	for (int i = 0; i < SIZE; ++i) {
484	assertEquals(new PDelay(i), q.remove());
485	}
486	try {
487	q.remove();
488	shouldThrow();
489	} catch (NoSuchElementException success) {}
490	}
491
492	/**
493	* contains(x) reports true when elements added but not yet removed
494	*/
495	public void testContains() {
496	DelayQueue q = populatedQueue(SIZE);
497	for (int i = 0; i < SIZE; ++i) {
498	assertTrue(q.contains(new PDelay(i)));
499	q.poll();
500	assertFalse(q.contains(new PDelay(i)));
501	}
502	}
503
504	/**
505	* clear removes all elements
506	*/
507	public void testClear() {
508	DelayQueue q = populatedQueue(SIZE);
509	q.clear();
510	assertTrue(q.isEmpty());
511	assertEquals(0, q.size());
512	assertEquals(NOCAP, q.remainingCapacity());
513	PDelay x = new PDelay(1);
514	q.add(x);
515	assertFalse(q.isEmpty());
516	assertTrue(q.contains(x));
517	q.clear();
518	assertTrue(q.isEmpty());
519	}
520
521	/**
522	* containsAll(c) is true when c contains a subset of elements
523	*/
524	public void testContainsAll() {
525	DelayQueue q = populatedQueue(SIZE);
526	DelayQueue p = new DelayQueue();
527	for (int i = 0; i < SIZE; ++i) {
528	assertTrue(q.containsAll(p));
529	assertFalse(p.containsAll(q));
530	p.add(new PDelay(i));
531	}
532	assertTrue(p.containsAll(q));
533	}
534
535	/**
536	* retainAll(c) retains only those elements of c and reports true if changed
537	*/
538	public void testRetainAll() {
539	DelayQueue q = populatedQueue(SIZE);
540	DelayQueue p = populatedQueue(SIZE);
541	for (int i = 0; i < SIZE; ++i) {
542	boolean changed = q.retainAll(p);
543	if (i == 0)
544	assertFalse(changed);
545	else
546	assertTrue(changed);
547
548	assertTrue(q.containsAll(p));
549	assertEquals(SIZE-i, q.size());
550	p.remove();
551	}
552	}
553
554	/**
555	* removeAll(c) removes only those elements of c and reports true if changed
556	*/
557	public void testRemoveAll() {
558	for (int i = 1; i < SIZE; ++i) {
559	DelayQueue q = populatedQueue(SIZE);
560	DelayQueue p = populatedQueue(i);
561	assertTrue(q.removeAll(p));
562	assertEquals(SIZE-i, q.size());
563	for (int j = 0; j < i; ++j) {
564	PDelay x = (PDelay)(p.remove());
565	assertFalse(q.contains(x));
566	}
567	}
568	}
569
570	/**
571	* toArray contains all elements
572	*/
573	public void testToArray() throws InterruptedException {
574	DelayQueue q = populatedQueue(SIZE);
575	Object[] o = q.toArray();
576	Arrays.sort(o);
577	for (int i = 0; i < o.length; i++)
578	assertSame(o[i], q.take());
579	}
580
581	/**
582	* toArray(a) contains all elements
583	*/
584	public void testToArray2() {
585	DelayQueue<PDelay> q = populatedQueue(SIZE);
586	PDelay[] ints = new PDelay[SIZE];
587	PDelay[] array = q.toArray(ints);
588	assertSame(ints, array);
589	Arrays.sort(ints);
590	for (int i = 0; i < ints.length; i++)
591	assertSame(ints[i], q.remove());
592	}
593
594	/**
595	* toArray(incompatible array type) throws ArrayStoreException
596	*/
597	public void testToArray1_BadArg() {
598	DelayQueue q = populatedQueue(SIZE);
599	try {
600	q.toArray(new String[10]);
601	shouldThrow();
602	} catch (ArrayStoreException success) {}
603	}
604
605	/**
606	* iterator iterates through all elements
607	*/
608	public void testIterator() {
609	DelayQueue q = populatedQueue(SIZE);
610	int i = 0;
611	Iterator it = q.iterator();
612	while (it.hasNext()) {
613	assertTrue(q.contains(it.next()));
614	++i;
615	}
616	assertEquals(i, SIZE);
617	assertIteratorExhausted(it);
618	}
619
620	/**
621	* iterator of empty collection has no elements
622	*/
623	public void testEmptyIterator() {
624	assertIteratorExhausted(new DelayQueue().iterator());
625	}
626
627	/**
628	* iterator.remove removes current element
629	*/
630	public void testIteratorRemove() {
631	final DelayQueue q = new DelayQueue();
632	q.add(new PDelay(2));
633	q.add(new PDelay(1));
634	q.add(new PDelay(3));
635	Iterator it = q.iterator();
636	it.next();
637	it.remove();
638	it = q.iterator();
639	assertEquals(new PDelay(2), it.next());
640	assertEquals(new PDelay(3), it.next());
641	assertFalse(it.hasNext());
642	}
643
644	/**
645	* toString contains toStrings of elements
646	*/
647	public void testToString() {
648	DelayQueue q = populatedQueue(SIZE);
649	String s = q.toString();
650	for (Object e : q)
651	assertTrue(s.contains(e.toString()));
652	}
653
654	/**
655	* timed poll transfers elements across Executor tasks
656	*/
657	public void testPollInExecutor() {
658	final DelayQueue q = new DelayQueue();
659	final CheckedBarrier threadsStarted = new CheckedBarrier(2);
660	ExecutorService executor = Executors.newFixedThreadPool(2);
661	executor.execute(new CheckedRunnable() {
662	public void realRun() throws InterruptedException {
663	assertNull(q.poll());
664	threadsStarted.await();
665	assertNotNull(q.poll(LONG_DELAY_MS, MILLISECONDS));
666	checkEmpty(q);
667	}});
668
669	executor.execute(new CheckedRunnable() {
670	public void realRun() throws InterruptedException {
671	threadsStarted.await();
672	q.put(new PDelay(1));
673	}});
674
675	joinPool(executor);
676	}
677
678	/**
679	* Delayed actions do not occur until their delay elapses
680	*/
681	public void testDelay() throws InterruptedException {
682	DelayQueue<NanoDelay> q = new DelayQueue<NanoDelay>();
683	for (int i = 0; i < SIZE; ++i)
684	q.add(new NanoDelay(1000000L * (SIZE - i)));
685
686	long last = 0;
687	for (int i = 0; i < SIZE; ++i) {
688	NanoDelay e = q.take();
689	long tt = e.getTriggerTime();
690	assertTrue(System.nanoTime() - tt >= 0);
691	if (i != 0)
692	assertTrue(tt >= last);
693	last = tt;
694	}
695	assertTrue(q.isEmpty());
696	}
697
698	/**
699	* peek of a non-empty queue returns non-null even if not expired
700	*/
701	public void testPeekDelayed() {
702	DelayQueue q = new DelayQueue();
703	q.add(new NanoDelay(Long.MAX_VALUE));
704	assertNotNull(q.peek());
705	}
706
707	/**
708	* poll of a non-empty queue returns null if no expired elements.
709	*/
710	public void testPollDelayed() {
711	DelayQueue q = new DelayQueue();
712	q.add(new NanoDelay(Long.MAX_VALUE));
713	assertNull(q.poll());
714	}
715
716	/**
717	* timed poll of a non-empty queue returns null if no expired elements.
718	*/
719	public void testTimedPollDelayed() throws InterruptedException {
720	DelayQueue q = new DelayQueue();
721	q.add(new NanoDelay(LONG_DELAY_MS * 1000000L));
722	assertNull(q.poll(timeoutMillis(), MILLISECONDS));
723	}
724
725	/**
726	* drainTo(c) empties queue into another collection c
727	*/
728	public void testDrainTo() {
729	DelayQueue q = new DelayQueue();
730	PDelay[] elems = new PDelay[SIZE];
731	for (int i = 0; i < SIZE; ++i) {
732	elems[i] = new PDelay(i);
733	q.add(elems[i]);
734	}
735	ArrayList l = new ArrayList();
736	q.drainTo(l);
737	assertEquals(0, q.size());
738	for (int i = 0; i < SIZE; ++i)
739	assertEquals(elems[i], l.get(i));
740	q.add(elems[0]);
741	q.add(elems[1]);
742	assertFalse(q.isEmpty());
743	assertTrue(q.contains(elems[0]));
744	assertTrue(q.contains(elems[1]));
745	l.clear();
746	q.drainTo(l);
747	assertEquals(0, q.size());
748	assertEquals(2, l.size());
749	for (int i = 0; i < 2; ++i)
750	assertEquals(elems[i], l.get(i));
751	}
752
753	/**
754	* drainTo empties queue
755	*/
756	public void testDrainToWithActivePut() throws InterruptedException {
757	final DelayQueue q = populatedQueue(SIZE);
758	Thread t = new Thread(new CheckedRunnable() {
759	public void realRun() {
760	q.put(new PDelay(SIZE+1));
761	}});
762
763	t.start();
764	ArrayList l = new ArrayList();
765	q.drainTo(l);
766	assertTrue(l.size() >= SIZE);
767	t.join();
768	assertTrue(q.size() + l.size() >= SIZE);
769	}
770
771	/**
772	* drainTo(c, n) empties first min(n, size) elements of queue into c
773	*/
774	public void testDrainToN() {
775	for (int i = 0; i < SIZE + 2; ++i) {
776	DelayQueue q = populatedQueue(SIZE);
777	ArrayList l = new ArrayList();
778	q.drainTo(l, i);
779	int k = (i < SIZE) ? i : SIZE;
780	assertEquals(SIZE-k, q.size());
781	assertEquals(k, l.size());
782	}
783	}
784
785	/**
786	* remove(null), contains(null) always return false
787	*/
788	public void testNeverContainsNull() {
789	Collection<?> q = populatedQueue(SIZE);
790	assertFalse(q.contains(null));
791	assertFalse(q.remove(null));
792	}
793	}