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) {
        main(suite(), args);
    }

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

    /**
     * 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(Integer.MAX_VALUE, q.remainingCapacity());
        assertEquals(n, q.size());
        return q;
    }

    /**
     * A new queue has unbounded capacity
     */
    public void testConstructor1() {
        assertEquals(Integer.MAX_VALUE, 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 {
            new DelayQueue(Arrays.asList(new PDelay[SIZE]));
            shouldThrow();
        } catch (NullPointerException success) {}
    }

    /**
     * Initializing from Collection with some null elements throws NPE
     */
    public void testConstructor5() {
        PDelay[] a = new PDelay[SIZE];
        for (int i = 0; i < SIZE-1; ++i)
            a[i] = new PDelay(i);
        try {
            new DelayQueue(Arrays.asList(a));
            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(Integer.MAX_VALUE, q.remainingCapacity());
        q.add(new PDelay(1));
        assertFalse(q.isEmpty());
        q.add(new PDelay(2));
        q.remove();
        q.remove();
        assertTrue(q.isEmpty());
    }

    /**
     * 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());
            assertTrue(q.remove() instanceof PDelay);
        }
        for (int i = 0; i < SIZE; ++i) {
            assertEquals(Integer.MAX_VALUE, q.remainingCapacity());
            assertEquals(i, q.size());
            assertTrue(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() {
        DelayQueue q = populatedQueue(SIZE);
        try {
            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() {
        DelayQueue q = new DelayQueue();
        PDelay[] a = new PDelay[SIZE];
        for (int i = 0; i < SIZE-1; ++i)
            a[i] = new PDelay(i);
        try {
            q.addAll(Arrays.asList(a));
            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(Integer.MAX_VALUE, 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:	1.72
Committed:	Fri May 15 18:21:19 2015 UTC (8 years, 11 months ago) by jsr166
Branch:	MAIN
Changes since 1.71:	+11 -12 lines
Log Message:	try/catch block scope hygiene
#	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	main(suite(), args);
39	}
40
41	public static Test suite() {
42	return newTestSuite(DelayQueueTest.class,
43	new Generic().testSuite());
44	}
45
46	/**
47	* A delayed implementation for testing.
48	* Most tests use Pseudodelays, where delays are all elapsed
49	* (so, no blocking solely for delays) but are still ordered
50	*/
51	static class PDelay implements Delayed {
52	int pseudodelay;
53	PDelay(int i) { pseudodelay = i; }
54	public int compareTo(PDelay other) {
55	int a = this.pseudodelay;
56	int b = other.pseudodelay;
57	return (a < b) ? -1 : (a > b) ? 1 : 0;
58	}
59	public int compareTo(Delayed y) {
60	return compareTo((PDelay)y);
61	}
62	public boolean equals(Object other) {
63	return (other instanceof PDelay) &&
64	this.pseudodelay == ((PDelay)other).pseudodelay;
65	}
66	// suppress [overrides] javac warning
67	public int hashCode() { return pseudodelay; }
68	public long getDelay(TimeUnit ignore) {
69	return Integer.MIN_VALUE + pseudodelay;
70	}
71	public String toString() {
72	return String.valueOf(pseudodelay);
73	}
74	}
75
76	/**
77	* Delayed implementation that actually delays
78	*/
79	static class NanoDelay implements Delayed {
80	long trigger;
81	NanoDelay(long i) {
82	trigger = System.nanoTime() + i;
83	}
84	public int compareTo(NanoDelay y) {
85	long i = trigger;
86	long j = y.trigger;
87	if (i < j) return -1;
88	if (i > j) return 1;
89	return 0;
90	}
91
92	public int compareTo(Delayed y) {
93	return compareTo((NanoDelay)y);
94	}
95
96	public boolean equals(Object other) {
97	return equals((NanoDelay)other);
98	}
99	public boolean equals(NanoDelay other) {
100	return other.trigger == trigger;
101	}
102
103	// suppress [overrides] javac warning
104	public int hashCode() { return (int) trigger; }
105
106	public long getDelay(TimeUnit unit) {
107	long n = trigger - System.nanoTime();
108	return unit.convert(n, TimeUnit.NANOSECONDS);
109	}
110
111	public long getTriggerTime() {
112	return trigger;
113	}
114
115	public String toString() {
116	return String.valueOf(trigger);
117	}
118	}
119
120	/**
121	* Returns a new queue of given size containing consecutive
122	* PDelays 0 ... n.
123	*/
124	private DelayQueue<PDelay> populatedQueue(int n) {
125	DelayQueue<PDelay> q = new DelayQueue<PDelay>();
126	assertTrue(q.isEmpty());
127	for (int i = n-1; i >= 0; i -= 2)
128	assertTrue(q.offer(new PDelay(i)));
129	for (int i = (n & 1); i < n; i += 2)
130	assertTrue(q.offer(new PDelay(i)));
131	assertFalse(q.isEmpty());
132	assertEquals(Integer.MAX_VALUE, q.remainingCapacity());
133	assertEquals(n, q.size());
134	return q;
135	}
136
137	/**
138	* A new queue has unbounded capacity
139	*/
140	public void testConstructor1() {
141	assertEquals(Integer.MAX_VALUE, new DelayQueue().remainingCapacity());
142	}
143
144	/**
145	* Initializing from null Collection throws NPE
146	*/
147	public void testConstructor3() {
148	try {
149	new DelayQueue(null);
150	shouldThrow();
151	} catch (NullPointerException success) {}
152	}
153
154	/**
155	* Initializing from Collection of null elements throws NPE
156	*/
157	public void testConstructor4() {
158	try {
159	new DelayQueue(Arrays.asList(new PDelay[SIZE]));
160	shouldThrow();
161	} catch (NullPointerException success) {}
162	}
163
164	/**
165	* Initializing from Collection with some null elements throws NPE
166	*/
167	public void testConstructor5() {
168	PDelay[] a = new PDelay[SIZE];
169	for (int i = 0; i < SIZE-1; ++i)
170	a[i] = new PDelay(i);
171	try {
172	new DelayQueue(Arrays.asList(a));
173	shouldThrow();
174	} catch (NullPointerException success) {}
175	}
176
177	/**
178	* Queue contains all elements of collection used to initialize
179	*/
180	public void testConstructor6() {
181	PDelay[] ints = new PDelay[SIZE];
182	for (int i = 0; i < SIZE; ++i)
183	ints[i] = new PDelay(i);
184	DelayQueue q = new DelayQueue(Arrays.asList(ints));
185	for (int i = 0; i < SIZE; ++i)
186	assertEquals(ints[i], q.poll());
187	}
188
189	/**
190	* isEmpty is true before add, false after
191	*/
192	public void testEmpty() {
193	DelayQueue q = new DelayQueue();
194	assertTrue(q.isEmpty());
195	assertEquals(Integer.MAX_VALUE, q.remainingCapacity());
196	q.add(new PDelay(1));
197	assertFalse(q.isEmpty());
198	q.add(new PDelay(2));
199	q.remove();
200	q.remove();
201	assertTrue(q.isEmpty());
202	}
203
204	/**
205	* remainingCapacity() always returns Integer.MAX_VALUE
206	*/
207	public void testRemainingCapacity() {
208	BlockingQueue q = populatedQueue(SIZE);
209	for (int i = 0; i < SIZE; ++i) {
210	assertEquals(Integer.MAX_VALUE, q.remainingCapacity());
211	assertEquals(SIZE-i, q.size());
212	assertTrue(q.remove() instanceof PDelay);
213	}
214	for (int i = 0; i < SIZE; ++i) {
215	assertEquals(Integer.MAX_VALUE, q.remainingCapacity());
216	assertEquals(i, q.size());
217	assertTrue(q.add(new PDelay(i)));
218	}
219	}
220
221	/**
222	* offer non-null succeeds
223	*/
224	public void testOffer() {
225	DelayQueue q = new DelayQueue();
226	assertTrue(q.offer(new PDelay(0)));
227	assertTrue(q.offer(new PDelay(1)));
228	}
229
230	/**
231	* add succeeds
232	*/
233	public void testAdd() {
234	DelayQueue q = new DelayQueue();
235	for (int i = 0; i < SIZE; ++i) {
236	assertEquals(i, q.size());
237	assertTrue(q.add(new PDelay(i)));
238	}
239	}
240
241	/**
242	* addAll(this) throws IAE
243	*/
244	public void testAddAllSelf() {
245	DelayQueue q = populatedQueue(SIZE);
246	try {
247	q.addAll(q);
248	shouldThrow();
249	} catch (IllegalArgumentException success) {}
250	}
251
252	/**
253	* addAll of a collection with any null elements throws NPE after
254	* possibly adding some elements
255	*/
256	public void testAddAll3() {
257	DelayQueue q = new DelayQueue();
258	PDelay[] a = new PDelay[SIZE];
259	for (int i = 0; i < SIZE-1; ++i)
260	a[i] = new PDelay(i);
261	try {
262	q.addAll(Arrays.asList(a));
263	shouldThrow();
264	} catch (NullPointerException success) {}
265	}
266
267	/**
268	* Queue contains all elements of successful addAll
269	*/
270	public void testAddAll5() {
271	PDelay[] empty = new PDelay[0];
272	PDelay[] ints = new PDelay[SIZE];
273	for (int i = SIZE-1; i >= 0; --i)
274	ints[i] = new PDelay(i);
275	DelayQueue q = new DelayQueue();
276	assertFalse(q.addAll(Arrays.asList(empty)));
277	assertTrue(q.addAll(Arrays.asList(ints)));
278	for (int i = 0; i < SIZE; ++i)
279	assertEquals(ints[i], q.poll());
280	}
281
282	/**
283	* all elements successfully put are contained
284	*/
285	public void testPut() {
286	DelayQueue q = new DelayQueue();
287	for (int i = 0; i < SIZE; ++i) {
288	PDelay x = new PDelay(i);
289	q.put(x);
290	assertTrue(q.contains(x));
291	}
292	assertEquals(SIZE, q.size());
293	}
294
295	/**
296	* put doesn't block waiting for take
297	*/
298	public void testPutWithTake() throws InterruptedException {
299	final DelayQueue q = new DelayQueue();
300	Thread t = newStartedThread(new CheckedRunnable() {
301	public void realRun() {
302	q.put(new PDelay(0));
303	q.put(new PDelay(0));
304	q.put(new PDelay(0));
305	q.put(new PDelay(0));
306	}});
307
308	awaitTermination(t);
309	assertEquals(4, q.size());
310	}
311
312	/**
313	* timed offer does not time out
314	*/
315	public void testTimedOffer() throws InterruptedException {
316	final DelayQueue q = new DelayQueue();
317	Thread t = newStartedThread(new CheckedRunnable() {
318	public void realRun() throws InterruptedException {
319	q.put(new PDelay(0));
320	q.put(new PDelay(0));
321	assertTrue(q.offer(new PDelay(0), SHORT_DELAY_MS, MILLISECONDS));
322	assertTrue(q.offer(new PDelay(0), LONG_DELAY_MS, MILLISECONDS));
323	}});
324
325	awaitTermination(t);
326	}
327
328	/**
329	* take retrieves elements in priority order
330	*/
331	public void testTake() throws InterruptedException {
332	DelayQueue q = populatedQueue(SIZE);
333	for (int i = 0; i < SIZE; ++i) {
334	assertEquals(new PDelay(i), q.take());
335	}
336	}
337
338	/**
339	* Take removes existing elements until empty, then blocks interruptibly
340	*/
341	public void testBlockingTake() throws InterruptedException {
342	final DelayQueue q = populatedQueue(SIZE);
343	final CountDownLatch pleaseInterrupt = new CountDownLatch(1);
344	Thread t = newStartedThread(new CheckedRunnable() {
345	public void realRun() throws InterruptedException {
346	for (int i = 0; i < SIZE; ++i) {
347	assertEquals(new PDelay(i), ((PDelay)q.take()));
348	}
349
350	Thread.currentThread().interrupt();
351	try {
352	q.take();
353	shouldThrow();
354	} catch (InterruptedException success) {}
355	assertFalse(Thread.interrupted());
356
357	pleaseInterrupt.countDown();
358	try {
359	q.take();
360	shouldThrow();
361	} catch (InterruptedException success) {}
362	assertFalse(Thread.interrupted());
363	}});
364
365	await(pleaseInterrupt);
366	assertThreadStaysAlive(t);
367	t.interrupt();
368	awaitTermination(t);
369	}
370
371	/**
372	* poll succeeds unless empty
373	*/
374	public void testPoll() {
375	DelayQueue q = populatedQueue(SIZE);
376	for (int i = 0; i < SIZE; ++i) {
377	assertEquals(new PDelay(i), q.poll());
378	}
379	assertNull(q.poll());
380	}
381
382	/**
383	* timed poll with zero timeout succeeds when non-empty, else times out
384	*/
385	public void testTimedPoll0() throws InterruptedException {
386	DelayQueue q = populatedQueue(SIZE);
387	for (int i = 0; i < SIZE; ++i) {
388	assertEquals(new PDelay(i), q.poll(0, MILLISECONDS));
389	}
390	assertNull(q.poll(0, MILLISECONDS));
391	}
392
393	/**
394	* timed poll with nonzero timeout succeeds when non-empty, else times out
395	*/
396	public void testTimedPoll() throws InterruptedException {
397	DelayQueue q = populatedQueue(SIZE);
398	for (int i = 0; i < SIZE; ++i) {
399	long startTime = System.nanoTime();
400	assertEquals(new PDelay(i), q.poll(LONG_DELAY_MS, MILLISECONDS));
401	assertTrue(millisElapsedSince(startTime) < LONG_DELAY_MS);
402	}
403	long startTime = System.nanoTime();
404	assertNull(q.poll(timeoutMillis(), MILLISECONDS));
405	assertTrue(millisElapsedSince(startTime) >= timeoutMillis());
406	checkEmpty(q);
407	}
408
409	/**
410	* Interrupted timed poll throws InterruptedException instead of
411	* returning timeout status
412	*/
413	public void testInterruptedTimedPoll() throws InterruptedException {
414	final CountDownLatch pleaseInterrupt = new CountDownLatch(1);
415	Thread t = newStartedThread(new CheckedRunnable() {
416	public void realRun() throws InterruptedException {
417	DelayQueue q = populatedQueue(SIZE);
418	for (int i = 0; i < SIZE; ++i) {
419	assertEquals(new PDelay(i), ((PDelay)q.poll(SHORT_DELAY_MS, MILLISECONDS)));
420	}
421
422	Thread.currentThread().interrupt();
423	try {
424	q.poll(LONG_DELAY_MS, MILLISECONDS);
425	shouldThrow();
426	} catch (InterruptedException success) {}
427	assertFalse(Thread.interrupted());
428
429	pleaseInterrupt.countDown();
430	try {
431	q.poll(LONG_DELAY_MS, MILLISECONDS);
432	shouldThrow();
433	} catch (InterruptedException success) {}
434	assertFalse(Thread.interrupted());
435	}});
436
437	await(pleaseInterrupt);
438	assertThreadStaysAlive(t);
439	t.interrupt();
440	awaitTermination(t);
441	}
442
443	/**
444	* peek returns next element, or null if empty
445	*/
446	public void testPeek() {
447	DelayQueue q = populatedQueue(SIZE);
448	for (int i = 0; i < SIZE; ++i) {
449	assertEquals(new PDelay(i), q.peek());
450	assertEquals(new PDelay(i), q.poll());
451	if (q.isEmpty())
452	assertNull(q.peek());
453	else
454	assertFalse(new PDelay(i).equals(q.peek()));
455	}
456	assertNull(q.peek());
457	}
458
459	/**
460	* element returns next element, or throws NSEE if empty
461	*/
462	public void testElement() {
463	DelayQueue q = populatedQueue(SIZE);
464	for (int i = 0; i < SIZE; ++i) {
465	assertEquals(new PDelay(i), q.element());
466	q.poll();
467	}
468	try {
469	q.element();
470	shouldThrow();
471	} catch (NoSuchElementException success) {}
472	}
473
474	/**
475	* remove removes next element, or throws NSEE if empty
476	*/
477	public void testRemove() {
478	DelayQueue q = populatedQueue(SIZE);
479	for (int i = 0; i < SIZE; ++i) {
480	assertEquals(new PDelay(i), q.remove());
481	}
482	try {
483	q.remove();
484	shouldThrow();
485	} catch (NoSuchElementException success) {}
486	}
487
488	/**
489	* contains(x) reports true when elements added but not yet removed
490	*/
491	public void testContains() {
492	DelayQueue q = populatedQueue(SIZE);
493	for (int i = 0; i < SIZE; ++i) {
494	assertTrue(q.contains(new PDelay(i)));
495	q.poll();
496	assertFalse(q.contains(new PDelay(i)));
497	}
498	}
499
500	/**
501	* clear removes all elements
502	*/
503	public void testClear() {
504	DelayQueue q = populatedQueue(SIZE);
505	q.clear();
506	assertTrue(q.isEmpty());
507	assertEquals(0, q.size());
508	assertEquals(Integer.MAX_VALUE, q.remainingCapacity());
509	PDelay x = new PDelay(1);
510	q.add(x);
511	assertFalse(q.isEmpty());
512	assertTrue(q.contains(x));
513	q.clear();
514	assertTrue(q.isEmpty());
515	}
516
517	/**
518	* containsAll(c) is true when c contains a subset of elements
519	*/
520	public void testContainsAll() {
521	DelayQueue q = populatedQueue(SIZE);
522	DelayQueue p = new DelayQueue();
523	for (int i = 0; i < SIZE; ++i) {
524	assertTrue(q.containsAll(p));
525	assertFalse(p.containsAll(q));
526	p.add(new PDelay(i));
527	}
528	assertTrue(p.containsAll(q));
529	}
530
531	/**
532	* retainAll(c) retains only those elements of c and reports true if changed
533	*/
534	public void testRetainAll() {
535	DelayQueue q = populatedQueue(SIZE);
536	DelayQueue p = populatedQueue(SIZE);
537	for (int i = 0; i < SIZE; ++i) {
538	boolean changed = q.retainAll(p);
539	if (i == 0)
540	assertFalse(changed);
541	else
542	assertTrue(changed);
543
544	assertTrue(q.containsAll(p));
545	assertEquals(SIZE-i, q.size());
546	p.remove();
547	}
548	}
549
550	/**
551	* removeAll(c) removes only those elements of c and reports true if changed
552	*/
553	public void testRemoveAll() {
554	for (int i = 1; i < SIZE; ++i) {
555	DelayQueue q = populatedQueue(SIZE);
556	DelayQueue p = populatedQueue(i);
557	assertTrue(q.removeAll(p));
558	assertEquals(SIZE-i, q.size());
559	for (int j = 0; j < i; ++j) {
560	PDelay x = (PDelay)(p.remove());
561	assertFalse(q.contains(x));
562	}
563	}
564	}
565
566	/**
567	* toArray contains all elements
568	*/
569	public void testToArray() throws InterruptedException {
570	DelayQueue q = populatedQueue(SIZE);
571	Object[] o = q.toArray();
572	Arrays.sort(o);
573	for (int i = 0; i < o.length; i++)
574	assertSame(o[i], q.take());
575	}
576
577	/**
578	* toArray(a) contains all elements
579	*/
580	public void testToArray2() {
581	DelayQueue<PDelay> q = populatedQueue(SIZE);
582	PDelay[] ints = new PDelay[SIZE];
583	PDelay[] array = q.toArray(ints);
584	assertSame(ints, array);
585	Arrays.sort(ints);
586	for (int i = 0; i < ints.length; i++)
587	assertSame(ints[i], q.remove());
588	}
589
590	/**
591	* toArray(incompatible array type) throws ArrayStoreException
592	*/
593	public void testToArray1_BadArg() {
594	DelayQueue q = populatedQueue(SIZE);
595	try {
596	q.toArray(new String[10]);
597	shouldThrow();
598	} catch (ArrayStoreException success) {}
599	}
600
601	/**
602	* iterator iterates through all elements
603	*/
604	public void testIterator() {
605	DelayQueue q = populatedQueue(SIZE);
606	int i = 0;
607	Iterator it = q.iterator();
608	while (it.hasNext()) {
609	assertTrue(q.contains(it.next()));
610	++i;
611	}
612	assertEquals(i, SIZE);
613	assertIteratorExhausted(it);
614	}
615
616	/**
617	* iterator of empty collection has no elements
618	*/
619	public void testEmptyIterator() {
620	assertIteratorExhausted(new DelayQueue().iterator());
621	}
622
623	/**
624	* iterator.remove removes current element
625	*/
626	public void testIteratorRemove() {
627	final DelayQueue q = new DelayQueue();
628	q.add(new PDelay(2));
629	q.add(new PDelay(1));
630	q.add(new PDelay(3));
631	Iterator it = q.iterator();
632	it.next();
633	it.remove();
634	it = q.iterator();
635	assertEquals(new PDelay(2), it.next());
636	assertEquals(new PDelay(3), it.next());
637	assertFalse(it.hasNext());
638	}
639
640	/**
641	* toString contains toStrings of elements
642	*/
643	public void testToString() {
644	DelayQueue q = populatedQueue(SIZE);
645	String s = q.toString();
646	for (Object e : q)
647	assertTrue(s.contains(e.toString()));
648	}
649
650	/**
651	* timed poll transfers elements across Executor tasks
652	*/
653	public void testPollInExecutor() {
654	final DelayQueue q = new DelayQueue();
655	final CheckedBarrier threadsStarted = new CheckedBarrier(2);
656	ExecutorService executor = Executors.newFixedThreadPool(2);
657	executor.execute(new CheckedRunnable() {
658	public void realRun() throws InterruptedException {
659	assertNull(q.poll());
660	threadsStarted.await();
661	assertNotNull(q.poll(LONG_DELAY_MS, MILLISECONDS));
662	checkEmpty(q);
663	}});
664
665	executor.execute(new CheckedRunnable() {
666	public void realRun() throws InterruptedException {
667	threadsStarted.await();
668	q.put(new PDelay(1));
669	}});
670
671	joinPool(executor);
672	}
673
674	/**
675	* Delayed actions do not occur until their delay elapses
676	*/
677	public void testDelay() throws InterruptedException {
678	DelayQueue<NanoDelay> q = new DelayQueue<NanoDelay>();
679	for (int i = 0; i < SIZE; ++i)
680	q.add(new NanoDelay(1000000L * (SIZE - i)));
681
682	long last = 0;
683	for (int i = 0; i < SIZE; ++i) {
684	NanoDelay e = q.take();
685	long tt = e.getTriggerTime();
686	assertTrue(System.nanoTime() - tt >= 0);
687	if (i != 0)
688	assertTrue(tt >= last);
689	last = tt;
690	}
691	assertTrue(q.isEmpty());
692	}
693
694	/**
695	* peek of a non-empty queue returns non-null even if not expired
696	*/
697	public void testPeekDelayed() {
698	DelayQueue q = new DelayQueue();
699	q.add(new NanoDelay(Long.MAX_VALUE));
700	assertNotNull(q.peek());
701	}
702
703	/**
704	* poll of a non-empty queue returns null if no expired elements.
705	*/
706	public void testPollDelayed() {
707	DelayQueue q = new DelayQueue();
708	q.add(new NanoDelay(Long.MAX_VALUE));
709	assertNull(q.poll());
710	}
711
712	/**
713	* timed poll of a non-empty queue returns null if no expired elements.
714	*/
715	public void testTimedPollDelayed() throws InterruptedException {
716	DelayQueue q = new DelayQueue();
717	q.add(new NanoDelay(LONG_DELAY_MS * 1000000L));
718	assertNull(q.poll(timeoutMillis(), MILLISECONDS));
719	}
720
721	/**
722	* drainTo(c) empties queue into another collection c
723	*/
724	public void testDrainTo() {
725	DelayQueue q = new DelayQueue();
726	PDelay[] elems = new PDelay[SIZE];
727	for (int i = 0; i < SIZE; ++i) {
728	elems[i] = new PDelay(i);
729	q.add(elems[i]);
730	}
731	ArrayList l = new ArrayList();
732	q.drainTo(l);
733	assertEquals(0, q.size());
734	for (int i = 0; i < SIZE; ++i)
735	assertEquals(elems[i], l.get(i));
736	q.add(elems[0]);
737	q.add(elems[1]);
738	assertFalse(q.isEmpty());
739	assertTrue(q.contains(elems[0]));
740	assertTrue(q.contains(elems[1]));
741	l.clear();
742	q.drainTo(l);
743	assertEquals(0, q.size());
744	assertEquals(2, l.size());
745	for (int i = 0; i < 2; ++i)
746	assertEquals(elems[i], l.get(i));
747	}
748
749	/**
750	* drainTo empties queue
751	*/
752	public void testDrainToWithActivePut() throws InterruptedException {
753	final DelayQueue q = populatedQueue(SIZE);
754	Thread t = new Thread(new CheckedRunnable() {
755	public void realRun() {
756	q.put(new PDelay(SIZE+1));
757	}});
758
759	t.start();
760	ArrayList l = new ArrayList();
761	q.drainTo(l);
762	assertTrue(l.size() >= SIZE);
763	t.join();
764	assertTrue(q.size() + l.size() >= SIZE);
765	}
766
767	/**
768	* drainTo(c, n) empties first min(n, size) elements of queue into c
769	*/
770	public void testDrainToN() {
771	for (int i = 0; i < SIZE + 2; ++i) {
772	DelayQueue q = populatedQueue(SIZE);
773	ArrayList l = new ArrayList();
774	q.drainTo(l, i);
775	int k = (i < SIZE) ? i : SIZE;
776	assertEquals(SIZE-k, q.size());
777	assertEquals(k, l.size());
778	}
779	}
780
781	/**
782	* remove(null), contains(null) always return false
783	*/
784	public void testNeverContainsNull() {
785	Collection<?> q = populatedQueue(SIZE);
786	assertFalse(q.contains(null));
787	assertFalse(q.remove(null));
788	}
789	}