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 junit.framework.*;
import java.util.Arrays;
import java.util.ArrayList;
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 static java.util.concurrent.TimeUnit.MILLISECONDS;

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;
        }
        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;
        }

        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);
        }
    }

    /**
     * Create a 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 {
            DelayQueue q = new DelayQueue(null);
            shouldThrow();
        } catch (NullPointerException success) {}
    }

    /**
     * Initializing from Collection of null elements throws NPE
     */
    public void testConstructor4() {
        try {
            PDelay[] ints = new PDelay[SIZE];
            DelayQueue q = 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);
            DelayQueue q = 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 I = new PDelay(i);
            q.put(I);
            assertTrue(q.contains(I));
        }
        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), ((PDelay)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), ((PDelay)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), ((PDelay)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), ((PDelay)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), ((PDelay)q.peek()));
            assertEquals(new PDelay(i), ((PDelay)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), ((PDelay)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), ((PDelay)q.remove()));
        }
        try {
            q.remove();
            shouldThrow();
        } catch (NoSuchElementException success) {}
    }

    /**
     * remove(x) removes x and returns true if present
     */
    public void testRemoveElement() {
        DelayQueue q = populatedQueue(SIZE);
        for (int i = 1; i < SIZE; i+=2) {
            assertTrue(q.remove(new PDelay(i)));
        }
        for (int i = 0; i < SIZE; i+=2) {
            assertTrue(q.remove(new PDelay(i)));
            assertFalse(q.remove(new PDelay(i+1)));
        }
        assertTrue(q.isEmpty());
    }

    /**
     * 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 I = (PDelay)(p.remove());
                assertFalse(q.contains(I));
            }
        }
    }

    /**
     * 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);
    }

    /**
     * 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(it.next(), new PDelay(2));
        assertEquals(it.next(), new PDelay(3));
        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();
                assertTrue(null != 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(q.size(), 0);
        for (int i = 0; i < SIZE; ++i)
            assertEquals(l.get(i), elems[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(q.size(), 0);
        assertEquals(l.size(), 2);
        for (int i = 0; i < 2; ++i)
            assertEquals(l.get(i), elems[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(q.size(), SIZE-k);
            assertEquals(l.size(), k);
        }
    }

}
Revision:	1.55
Committed:	Mon Jun 27 20:37:32 2011 UTC (12 years, 10 months ago) by jsr166
Branch:	MAIN
Changes since 1.54:	+10 -22 lines
Log Message:	cosmetic improvements to PDelay helper class
#	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 junit.framework.*;
10	import java.util.Arrays;
11	import java.util.ArrayList;
12	import java.util.Iterator;
13	import java.util.NoSuchElementException;
14	import java.util.concurrent.BlockingQueue;
15	import java.util.concurrent.CountDownLatch;
16	import java.util.concurrent.Delayed;
17	import java.util.concurrent.DelayQueue;
18	import java.util.concurrent.Executors;
19	import java.util.concurrent.ExecutorService;
20	import java.util.concurrent.TimeUnit;
21	import static java.util.concurrent.TimeUnit.MILLISECONDS;
22
23	public class DelayQueueTest extends JSR166TestCase {
24
25	public static class Generic extends BlockingQueueTest {
26	protected BlockingQueue emptyCollection() {
27	return new DelayQueue();
28	}
29	protected PDelay makeElement(int i) {
30	return new PDelay(i);
31	}
32	}
33
34	public static void main(String[] args) {
35	junit.textui.TestRunner.run(suite());
36	}
37
38	public static Test suite() {
39	return newTestSuite(DelayQueueTest.class,
40	new Generic().testSuite());
41	}
42
43	private static final int NOCAP = Integer.MAX_VALUE;
44
45	/**
46	* A delayed implementation for testing.
47	* Most tests use Pseudodelays, where delays are all elapsed
48	* (so, no blocking solely for delays) but are still ordered
49	*/
50	static class PDelay implements Delayed {
51	int pseudodelay;
52	PDelay(int i) { pseudodelay = i; }
53	public int compareTo(PDelay other) {
54	int a = this.pseudodelay;
55	int b = other.pseudodelay;
56	return (a < b) ? -1 : (a > b) ? 1 : 0;
57	}
58	public int compareTo(Delayed y) {
59	return compareTo((PDelay)y);
60	}
61	public boolean equals(Object other) {
62	return (other instanceof PDelay) &&
63	this.pseudodelay == ((PDelay)other).pseudodelay;
64	}
65	public long getDelay(TimeUnit ignore) {
66	return Integer.MIN_VALUE + pseudodelay;
67	}
68	public String toString() {
69	return String.valueOf(pseudodelay);
70	}
71	}
72
73	/**
74	* Delayed implementation that actually delays
75	*/
76	static class NanoDelay implements Delayed {
77	long trigger;
78	NanoDelay(long i) {
79	trigger = System.nanoTime() + i;
80	}
81	public int compareTo(NanoDelay y) {
82	long i = trigger;
83	long j = y.trigger;
84	if (i < j) return -1;
85	if (i > j) return 1;
86	return 0;
87	}
88
89	public int compareTo(Delayed y) {
90	return compareTo((NanoDelay)y);
91	}
92
93	public boolean equals(Object other) {
94	return equals((NanoDelay)other);
95	}
96	public boolean equals(NanoDelay other) {
97	return other.trigger == trigger;
98	}
99
100	public long getDelay(TimeUnit unit) {
101	long n = trigger - System.nanoTime();
102	return unit.convert(n, TimeUnit.NANOSECONDS);
103	}
104
105	public long getTriggerTime() {
106	return trigger;
107	}
108
109	public String toString() {
110	return String.valueOf(trigger);
111	}
112	}
113
114	/**
115	* Create a queue of given size containing consecutive
116	* PDelays 0 ... n.
117	*/
118	private DelayQueue<PDelay> populatedQueue(int n) {
119	DelayQueue<PDelay> q = new DelayQueue<PDelay>();
120	assertTrue(q.isEmpty());
121	for (int i = n-1; i >= 0; i-=2)
122	assertTrue(q.offer(new PDelay(i)));
123	for (int i = (n & 1); i < n; i+=2)
124	assertTrue(q.offer(new PDelay(i)));
125	assertFalse(q.isEmpty());
126	assertEquals(NOCAP, q.remainingCapacity());
127	assertEquals(n, q.size());
128	return q;
129	}
130
131	/**
132	* A new queue has unbounded capacity
133	*/
134	public void testConstructor1() {
135	assertEquals(NOCAP, new DelayQueue().remainingCapacity());
136	}
137
138	/**
139	* Initializing from null Collection throws NPE
140	*/
141	public void testConstructor3() {
142	try {
143	DelayQueue q = new DelayQueue(null);
144	shouldThrow();
145	} catch (NullPointerException success) {}
146	}
147
148	/**
149	* Initializing from Collection of null elements throws NPE
150	*/
151	public void testConstructor4() {
152	try {
153	PDelay[] ints = new PDelay[SIZE];
154	DelayQueue q = new DelayQueue(Arrays.asList(ints));
155	shouldThrow();
156	} catch (NullPointerException success) {}
157	}
158
159	/**
160	* Initializing from Collection with some null elements throws NPE
161	*/
162	public void testConstructor5() {
163	try {
164	PDelay[] ints = new PDelay[SIZE];
165	for (int i = 0; i < SIZE-1; ++i)
166	ints[i] = new PDelay(i);
167	DelayQueue q = new DelayQueue(Arrays.asList(ints));
168	shouldThrow();
169	} catch (NullPointerException success) {}
170	}
171
172	/**
173	* Queue contains all elements of collection used to initialize
174	*/
175	public void testConstructor6() {
176	PDelay[] ints = new PDelay[SIZE];
177	for (int i = 0; i < SIZE; ++i)
178	ints[i] = new PDelay(i);
179	DelayQueue q = new DelayQueue(Arrays.asList(ints));
180	for (int i = 0; i < SIZE; ++i)
181	assertEquals(ints[i], q.poll());
182	}
183
184	/**
185	* isEmpty is true before add, false after
186	*/
187	public void testEmpty() {
188	DelayQueue q = new DelayQueue();
189	assertTrue(q.isEmpty());
190	assertEquals(NOCAP, q.remainingCapacity());
191	q.add(new PDelay(1));
192	assertFalse(q.isEmpty());
193	q.add(new PDelay(2));
194	q.remove();
195	q.remove();
196	assertTrue(q.isEmpty());
197	}
198
199	/**
200	* remainingCapacity does not change when elements added or removed,
201	* but size does
202	*/
203	public void testRemainingCapacity() {
204	DelayQueue q = populatedQueue(SIZE);
205	for (int i = 0; i < SIZE; ++i) {
206	assertEquals(NOCAP, q.remainingCapacity());
207	assertEquals(SIZE-i, q.size());
208	q.remove();
209	}
210	for (int i = 0; i < SIZE; ++i) {
211	assertEquals(NOCAP, q.remainingCapacity());
212	assertEquals(i, q.size());
213	q.add(new PDelay(i));
214	}
215	}
216
217	/**
218	* offer non-null succeeds
219	*/
220	public void testOffer() {
221	DelayQueue q = new DelayQueue();
222	assertTrue(q.offer(new PDelay(0)));
223	assertTrue(q.offer(new PDelay(1)));
224	}
225
226	/**
227	* add succeeds
228	*/
229	public void testAdd() {
230	DelayQueue q = new DelayQueue();
231	for (int i = 0; i < SIZE; ++i) {
232	assertEquals(i, q.size());
233	assertTrue(q.add(new PDelay(i)));
234	}
235	}
236
237	/**
238	* addAll(this) throws IAE
239	*/
240	public void testAddAllSelf() {
241	try {
242	DelayQueue q = populatedQueue(SIZE);
243	q.addAll(q);
244	shouldThrow();
245	} catch (IllegalArgumentException success) {}
246	}
247
248	/**
249	* addAll of a collection with any null elements throws NPE after
250	* possibly adding some elements
251	*/
252	public void testAddAll3() {
253	try {
254	DelayQueue q = new DelayQueue();
255	PDelay[] ints = new PDelay[SIZE];
256	for (int i = 0; i < SIZE-1; ++i)
257	ints[i] = new PDelay(i);
258	q.addAll(Arrays.asList(ints));
259	shouldThrow();
260	} catch (NullPointerException success) {}
261	}
262
263	/**
264	* Queue contains all elements of successful addAll
265	*/
266	public void testAddAll5() {
267	PDelay[] empty = new PDelay[0];
268	PDelay[] ints = new PDelay[SIZE];
269	for (int i = SIZE-1; i >= 0; --i)
270	ints[i] = new PDelay(i);
271	DelayQueue q = new DelayQueue();
272	assertFalse(q.addAll(Arrays.asList(empty)));
273	assertTrue(q.addAll(Arrays.asList(ints)));
274	for (int i = 0; i < SIZE; ++i)
275	assertEquals(ints[i], q.poll());
276	}
277
278	/**
279	* all elements successfully put are contained
280	*/
281	public void testPut() {
282	DelayQueue q = new DelayQueue();
283	for (int i = 0; i < SIZE; ++i) {
284	PDelay I = new PDelay(i);
285	q.put(I);
286	assertTrue(q.contains(I));
287	}
288	assertEquals(SIZE, q.size());
289	}
290
291	/**
292	* put doesn't block waiting for take
293	*/
294	public void testPutWithTake() throws InterruptedException {
295	final DelayQueue q = new DelayQueue();
296	Thread t = newStartedThread(new CheckedRunnable() {
297	public void realRun() {
298	q.put(new PDelay(0));
299	q.put(new PDelay(0));
300	q.put(new PDelay(0));
301	q.put(new PDelay(0));
302	}});
303
304	awaitTermination(t);
305	assertEquals(4, q.size());
306	}
307
308	/**
309	* timed offer does not time out
310	*/
311	public void testTimedOffer() throws InterruptedException {
312	final DelayQueue q = new DelayQueue();
313	Thread t = newStartedThread(new CheckedRunnable() {
314	public void realRun() throws InterruptedException {
315	q.put(new PDelay(0));
316	q.put(new PDelay(0));
317	assertTrue(q.offer(new PDelay(0), SHORT_DELAY_MS, MILLISECONDS));
318	assertTrue(q.offer(new PDelay(0), LONG_DELAY_MS, MILLISECONDS));
319	}});
320
321	awaitTermination(t);
322	}
323
324	/**
325	* take retrieves elements in priority order
326	*/
327	public void testTake() throws InterruptedException {
328	DelayQueue q = populatedQueue(SIZE);
329	for (int i = 0; i < SIZE; ++i) {
330	assertEquals(new PDelay(i), ((PDelay)q.take()));
331	}
332	}
333
334	/**
335	* Take removes existing elements until empty, then blocks interruptibly
336	*/
337	public void testBlockingTake() throws InterruptedException {
338	final DelayQueue q = populatedQueue(SIZE);
339	final CountDownLatch pleaseInterrupt = new CountDownLatch(1);
340	Thread t = newStartedThread(new CheckedRunnable() {
341	public void realRun() throws InterruptedException {
342	for (int i = 0; i < SIZE; ++i) {
343	assertEquals(new PDelay(i), ((PDelay)q.take()));
344	}
345
346	Thread.currentThread().interrupt();
347	try {
348	q.take();
349	shouldThrow();
350	} catch (InterruptedException success) {}
351	assertFalse(Thread.interrupted());
352
353	pleaseInterrupt.countDown();
354	try {
355	q.take();
356	shouldThrow();
357	} catch (InterruptedException success) {}
358	assertFalse(Thread.interrupted());
359	}});
360
361	await(pleaseInterrupt);
362	assertThreadStaysAlive(t);
363	t.interrupt();
364	awaitTermination(t);
365	}
366
367	/**
368	* poll succeeds unless empty
369	*/
370	public void testPoll() {
371	DelayQueue q = populatedQueue(SIZE);
372	for (int i = 0; i < SIZE; ++i) {
373	assertEquals(new PDelay(i), ((PDelay)q.poll()));
374	}
375	assertNull(q.poll());
376	}
377
378	/**
379	* timed poll with zero timeout succeeds when non-empty, else times out
380	*/
381	public void testTimedPoll0() throws InterruptedException {
382	DelayQueue q = populatedQueue(SIZE);
383	for (int i = 0; i < SIZE; ++i) {
384	assertEquals(new PDelay(i), ((PDelay)q.poll(0, MILLISECONDS)));
385	}
386	assertNull(q.poll(0, MILLISECONDS));
387	}
388
389	/**
390	* timed poll with nonzero timeout succeeds when non-empty, else times out
391	*/
392	public void testTimedPoll() throws InterruptedException {
393	DelayQueue q = populatedQueue(SIZE);
394	for (int i = 0; i < SIZE; ++i) {
395	long startTime = System.nanoTime();
396	assertEquals(new PDelay(i), ((PDelay)q.poll(LONG_DELAY_MS, MILLISECONDS)));
397	assertTrue(millisElapsedSince(startTime) < LONG_DELAY_MS);
398	}
399	long startTime = System.nanoTime();
400	assertNull(q.poll(timeoutMillis(), MILLISECONDS));
401	assertTrue(millisElapsedSince(startTime) >= timeoutMillis());
402	checkEmpty(q);
403	}
404
405	/**
406	* Interrupted timed poll throws InterruptedException instead of
407	* returning timeout status
408	*/
409	public void testInterruptedTimedPoll() throws InterruptedException {
410	final CountDownLatch pleaseInterrupt = new CountDownLatch(1);
411	Thread t = newStartedThread(new CheckedRunnable() {
412	public void realRun() throws InterruptedException {
413	DelayQueue q = populatedQueue(SIZE);
414	for (int i = 0; i < SIZE; ++i) {
415	assertEquals(new PDelay(i), ((PDelay)q.poll(SHORT_DELAY_MS, MILLISECONDS)));
416	}
417
418	Thread.currentThread().interrupt();
419	try {
420	q.poll(LONG_DELAY_MS, MILLISECONDS);
421	shouldThrow();
422	} catch (InterruptedException success) {}
423	assertFalse(Thread.interrupted());
424
425	pleaseInterrupt.countDown();
426	try {
427	q.poll(LONG_DELAY_MS, MILLISECONDS);
428	shouldThrow();
429	} catch (InterruptedException success) {}
430	assertFalse(Thread.interrupted());
431	}});
432
433	await(pleaseInterrupt);
434	assertThreadStaysAlive(t);
435	t.interrupt();
436	awaitTermination(t);
437	}
438
439	/**
440	* peek returns next element, or null if empty
441	*/
442	public void testPeek() {
443	DelayQueue q = populatedQueue(SIZE);
444	for (int i = 0; i < SIZE; ++i) {
445	assertEquals(new PDelay(i), ((PDelay)q.peek()));
446	assertEquals(new PDelay(i), ((PDelay)q.poll()));
447	if (q.isEmpty())
448	assertNull(q.peek());
449	else
450	assertFalse(new PDelay(i).equals(q.peek()));
451	}
452	assertNull(q.peek());
453	}
454
455	/**
456	* element returns next element, or throws NSEE if empty
457	*/
458	public void testElement() {
459	DelayQueue q = populatedQueue(SIZE);
460	for (int i = 0; i < SIZE; ++i) {
461	assertEquals(new PDelay(i), ((PDelay)q.element()));
462	q.poll();
463	}
464	try {
465	q.element();
466	shouldThrow();
467	} catch (NoSuchElementException success) {}
468	}
469
470	/**
471	* remove removes next element, or throws NSEE if empty
472	*/
473	public void testRemove() {
474	DelayQueue q = populatedQueue(SIZE);
475	for (int i = 0; i < SIZE; ++i) {
476	assertEquals(new PDelay(i), ((PDelay)q.remove()));
477	}
478	try {
479	q.remove();
480	shouldThrow();
481	} catch (NoSuchElementException success) {}
482	}
483
484	/**
485	* remove(x) removes x and returns true if present
486	*/
487	public void testRemoveElement() {
488	DelayQueue q = populatedQueue(SIZE);
489	for (int i = 1; i < SIZE; i+=2) {
490	assertTrue(q.remove(new PDelay(i)));
491	}
492	for (int i = 0; i < SIZE; i+=2) {
493	assertTrue(q.remove(new PDelay(i)));
494	assertFalse(q.remove(new PDelay(i+1)));
495	}
496	assertTrue(q.isEmpty());
497	}
498
499	/**
500	* contains(x) reports true when elements added but not yet removed
501	*/
502	public void testContains() {
503	DelayQueue q = populatedQueue(SIZE);
504	for (int i = 0; i < SIZE; ++i) {
505	assertTrue(q.contains(new PDelay(i)));
506	q.poll();
507	assertFalse(q.contains(new PDelay(i)));
508	}
509	}
510
511	/**
512	* clear removes all elements
513	*/
514	public void testClear() {
515	DelayQueue q = populatedQueue(SIZE);
516	q.clear();
517	assertTrue(q.isEmpty());
518	assertEquals(0, q.size());
519	assertEquals(NOCAP, q.remainingCapacity());
520	PDelay x = new PDelay(1);
521	q.add(x);
522	assertFalse(q.isEmpty());
523	assertTrue(q.contains(x));
524	q.clear();
525	assertTrue(q.isEmpty());
526	}
527
528	/**
529	* containsAll(c) is true when c contains a subset of elements
530	*/
531	public void testContainsAll() {
532	DelayQueue q = populatedQueue(SIZE);
533	DelayQueue p = new DelayQueue();
534	for (int i = 0; i < SIZE; ++i) {
535	assertTrue(q.containsAll(p));
536	assertFalse(p.containsAll(q));
537	p.add(new PDelay(i));
538	}
539	assertTrue(p.containsAll(q));
540	}
541
542	/**
543	* retainAll(c) retains only those elements of c and reports true if changed
544	*/
545	public void testRetainAll() {
546	DelayQueue q = populatedQueue(SIZE);
547	DelayQueue p = populatedQueue(SIZE);
548	for (int i = 0; i < SIZE; ++i) {
549	boolean changed = q.retainAll(p);
550	if (i == 0)
551	assertFalse(changed);
552	else
553	assertTrue(changed);
554
555	assertTrue(q.containsAll(p));
556	assertEquals(SIZE-i, q.size());
557	p.remove();
558	}
559	}
560
561	/**
562	* removeAll(c) removes only those elements of c and reports true if changed
563	*/
564	public void testRemoveAll() {
565	for (int i = 1; i < SIZE; ++i) {
566	DelayQueue q = populatedQueue(SIZE);
567	DelayQueue p = populatedQueue(i);
568	assertTrue(q.removeAll(p));
569	assertEquals(SIZE-i, q.size());
570	for (int j = 0; j < i; ++j) {
571	PDelay I = (PDelay)(p.remove());
572	assertFalse(q.contains(I));
573	}
574	}
575	}
576
577	/**
578	* toArray contains all elements
579	*/
580	public void testToArray() throws InterruptedException {
581	DelayQueue q = populatedQueue(SIZE);
582	Object[] o = q.toArray();
583	Arrays.sort(o);
584	for (int i = 0; i < o.length; i++)
585	assertSame(o[i], q.take());
586	}
587
588	/**
589	* toArray(a) contains all elements
590	*/
591	public void testToArray2() {
592	DelayQueue<PDelay> q = populatedQueue(SIZE);
593	PDelay[] ints = new PDelay[SIZE];
594	PDelay[] array = q.toArray(ints);
595	assertSame(ints, array);
596	Arrays.sort(ints);
597	for (int i = 0; i < ints.length; i++)
598	assertSame(ints[i], q.remove());
599	}
600
601	/**
602	* toArray(incompatible array type) throws ArrayStoreException
603	*/
604	public void testToArray1_BadArg() {
605	DelayQueue q = populatedQueue(SIZE);
606	try {
607	q.toArray(new String[10]);
608	shouldThrow();
609	} catch (ArrayStoreException success) {}
610	}
611
612	/**
613	* iterator iterates through all elements
614	*/
615	public void testIterator() {
616	DelayQueue q = populatedQueue(SIZE);
617	int i = 0;
618	Iterator it = q.iterator();
619	while (it.hasNext()) {
620	assertTrue(q.contains(it.next()));
621	++i;
622	}
623	assertEquals(i, SIZE);
624	}
625
626	/**
627	* iterator.remove removes current element
628	*/
629	public void testIteratorRemove() {
630	final DelayQueue q = new DelayQueue();
631	q.add(new PDelay(2));
632	q.add(new PDelay(1));
633	q.add(new PDelay(3));
634	Iterator it = q.iterator();
635	it.next();
636	it.remove();
637	it = q.iterator();
638	assertEquals(it.next(), new PDelay(2));
639	assertEquals(it.next(), new PDelay(3));
640	assertFalse(it.hasNext());
641	}
642
643	/**
644	* toString contains toStrings of elements
645	*/
646	public void testToString() {
647	DelayQueue q = populatedQueue(SIZE);
648	String s = q.toString();
649	for (Object e : q)
650	assertTrue(s.contains(e.toString()));
651	}
652
653	/**
654	* timed poll transfers elements across Executor tasks
655	*/
656	public void testPollInExecutor() {
657	final DelayQueue q = new DelayQueue();
658	final CheckedBarrier threadsStarted = new CheckedBarrier(2);
659	ExecutorService executor = Executors.newFixedThreadPool(2);
660	executor.execute(new CheckedRunnable() {
661	public void realRun() throws InterruptedException {
662	assertNull(q.poll());
663	threadsStarted.await();
664	assertTrue(null != q.poll(LONG_DELAY_MS, MILLISECONDS));
665	checkEmpty(q);
666	}});
667
668	executor.execute(new CheckedRunnable() {
669	public void realRun() throws InterruptedException {
670	threadsStarted.await();
671	q.put(new PDelay(1));
672	}});
673
674	joinPool(executor);
675	}
676
677	/**
678	* Delayed actions do not occur until their delay elapses
679	*/
680	public void testDelay() throws InterruptedException {
681	DelayQueue<NanoDelay> q = new DelayQueue<NanoDelay>();
682	for (int i = 0; i < SIZE; ++i)
683	q.add(new NanoDelay(1000000L * (SIZE - i)));
684
685	long last = 0;
686	for (int i = 0; i < SIZE; ++i) {
687	NanoDelay e = q.take();
688	long tt = e.getTriggerTime();
689	assertTrue(System.nanoTime() - tt >= 0);
690	if (i != 0)
691	assertTrue(tt >= last);
692	last = tt;
693	}
694	assertTrue(q.isEmpty());
695	}
696
697	/**
698	* peek of a non-empty queue returns non-null even if not expired
699	*/
700	public void testPeekDelayed() {
701	DelayQueue q = new DelayQueue();
702	q.add(new NanoDelay(Long.MAX_VALUE));
703	assertNotNull(q.peek());
704	}
705
706	/**
707	* poll of a non-empty queue returns null if no expired elements.
708	*/
709	public void testPollDelayed() {
710	DelayQueue q = new DelayQueue();
711	q.add(new NanoDelay(Long.MAX_VALUE));
712	assertNull(q.poll());
713	}
714
715	/**
716	* timed poll of a non-empty queue returns null if no expired elements.
717	*/
718	public void testTimedPollDelayed() throws InterruptedException {
719	DelayQueue q = new DelayQueue();
720	q.add(new NanoDelay(LONG_DELAY_MS * 1000000L));
721	assertNull(q.poll(timeoutMillis(), MILLISECONDS));
722	}
723
724	/**
725	* drainTo(c) empties queue into another collection c
726	*/
727	public void testDrainTo() {
728	DelayQueue q = new DelayQueue();
729	PDelay[] elems = new PDelay[SIZE];
730	for (int i = 0; i < SIZE; ++i) {
731	elems[i] = new PDelay(i);
732	q.add(elems[i]);
733	}
734	ArrayList l = new ArrayList();
735	q.drainTo(l);
736	assertEquals(q.size(), 0);
737	for (int i = 0; i < SIZE; ++i)
738	assertEquals(l.get(i), elems[i]);
739	q.add(elems[0]);
740	q.add(elems[1]);
741	assertFalse(q.isEmpty());
742	assertTrue(q.contains(elems[0]));
743	assertTrue(q.contains(elems[1]));
744	l.clear();
745	q.drainTo(l);
746	assertEquals(q.size(), 0);
747	assertEquals(l.size(), 2);
748	for (int i = 0; i < 2; ++i)
749	assertEquals(l.get(i), elems[i]);
750	}
751
752	/**
753	* drainTo empties queue
754	*/
755	public void testDrainToWithActivePut() throws InterruptedException {
756	final DelayQueue q = populatedQueue(SIZE);
757	Thread t = new Thread(new CheckedRunnable() {
758	public void realRun() {
759	q.put(new PDelay(SIZE+1));
760	}});
761
762	t.start();
763	ArrayList l = new ArrayList();
764	q.drainTo(l);
765	assertTrue(l.size() >= SIZE);
766	t.join();
767	assertTrue(q.size() + l.size() >= SIZE);
768	}
769
770	/**
771	* drainTo(c, n) empties first min(n, size) elements of queue into c
772	*/
773	public void testDrainToN() {
774	for (int i = 0; i < SIZE + 2; ++i) {
775	DelayQueue q = populatedQueue(SIZE);
776	ArrayList l = new ArrayList();
777	q.drainTo(l, i);
778	int k = (i < SIZE) ? i : SIZE;
779	assertEquals(q.size(), SIZE-k);
780	assertEquals(l.size(), k);
781	}
782	}
783
784	}