test/tck/ConcurrentLinkedQueueTest.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.*;
import java.util.concurrent.*;
import java.io.*;

public class ConcurrentLinkedQueueTest extends JSR166TestCase {

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

    public static Test suite() {
        return new TestSuite(ConcurrentLinkedQueueTest.class);
    }

    /**
     * Create a queue of given size containing consecutive
     * Integers 0 ... n.
     */
    private ConcurrentLinkedQueue<Integer> populatedQueue(int n) {
        ConcurrentLinkedQueue<Integer> q = new ConcurrentLinkedQueue<Integer>();
        assertTrue(q.isEmpty());
        for (int i = 0; i < n; ++i)
            assertTrue(q.offer(new Integer(i)));
        assertFalse(q.isEmpty());
        assertEquals(n, q.size());
        return q;
    }

    /**
     * new queue is empty
     */
    public void testConstructor1() {
        assertEquals(0, new ConcurrentLinkedQueue().size());
    }

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

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

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

    /**
     * Queue contains all elements of collection used to initialize
     */
    public void testConstructor6() {
        Integer[] ints = new Integer[SIZE];
        for (int i = 0; i < SIZE; ++i)
            ints[i] = new Integer(i);
        ConcurrentLinkedQueue q = new ConcurrentLinkedQueue(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() {
        ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
        assertTrue(q.isEmpty());
        q.add(one);
        assertFalse(q.isEmpty());
        q.add(two);
        q.remove();
        q.remove();
        assertTrue(q.isEmpty());
    }

    /**
     * size changes when elements added and removed
     */
    public void testSize() {
        ConcurrentLinkedQueue q = populatedQueue(SIZE);
        for (int i = 0; i < SIZE; ++i) {
            assertEquals(SIZE-i, q.size());
            q.remove();
        }
        for (int i = 0; i < SIZE; ++i) {
            assertEquals(i, q.size());
            q.add(new Integer(i));
        }
    }

    /**
     * offer(null) throws NPE
     */
    public void testOfferNull() {
        try {
            ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
            q.offer(null);
            shouldThrow();
        } catch (NullPointerException success) {}
    }

    /**
     * add(null) throws NPE
     */
    public void testAddNull() {
        try {
            ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
            q.add(null);
            shouldThrow();
        } catch (NullPointerException success) {}
    }

    /**
     * Offer returns true
     */
    public void testOffer() {
        ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
        assertTrue(q.offer(zero));
        assertTrue(q.offer(one));
    }

    /**
     * add returns true
     */
    public void testAdd() {
        ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
        for (int i = 0; i < SIZE; ++i) {
            assertEquals(i, q.size());
            assertTrue(q.add(new Integer(i)));
        }
    }

    /**
     * addAll(null) throws NPE
     */
    public void testAddAll1() {
        try {
            ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
            q.addAll(null);
            shouldThrow();
        } catch (NullPointerException success) {}
    }

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

    /**
     * addAll of a collection with null elements throws NPE
     */
    public void testAddAll2() {
        try {
            ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
            Integer[] ints = new Integer[SIZE];
            q.addAll(Arrays.asList(ints));
            shouldThrow();
        } catch (NullPointerException success) {}
    }

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

    /**
     * Queue contains all elements, in traversal order, of successful addAll
     */
    public void testAddAll5() {
        Integer[] empty = new Integer[0];
        Integer[] ints = new Integer[SIZE];
        for (int i = 0; i < SIZE; ++i)
            ints[i] = new Integer(i);
        ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
        assertFalse(q.addAll(Arrays.asList(empty)));
        assertTrue(q.addAll(Arrays.asList(ints)));
        for (int i = 0; i < SIZE; ++i)
            assertEquals(ints[i], q.poll());
    }

    /**
     * poll succeeds unless empty
     */
    public void testPoll() {
        ConcurrentLinkedQueue q = populatedQueue(SIZE);
        for (int i = 0; i < SIZE; ++i) {
            assertEquals(i, q.poll());
        }
        assertNull(q.poll());
    }

    /**
     * peek returns next element, or null if empty
     */
    public void testPeek() {
        ConcurrentLinkedQueue q = populatedQueue(SIZE);
        for (int i = 0; i < SIZE; ++i) {
            assertEquals(i, q.peek());
            assertEquals(i, q.poll());
            assertTrue(q.peek() == null ||
                       !q.peek().equals(i));
        }
        assertNull(q.peek());
    }

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

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

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

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

    /**
     * clear removes all elements
     */
    public void testClear() {
        ConcurrentLinkedQueue q = populatedQueue(SIZE);
        q.clear();
        assertTrue(q.isEmpty());
        assertEquals(0, q.size());
        q.add(one);
        assertFalse(q.isEmpty());
        q.clear();
        assertTrue(q.isEmpty());
    }

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

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

    /**
     * toArray contains all elements in FIFO order
     */
    public void testToArray() {
        ConcurrentLinkedQueue q = populatedQueue(SIZE);
        Object[] o = q.toArray();
        for (int i = 0; i < o.length; i++)
            assertSame(o[i], q.poll());
    }

    /**
     * toArray(a) contains all elements in FIFO order
     */
    public void testToArray2() {
        ConcurrentLinkedQueue<Integer> q = populatedQueue(SIZE);
        Integer[] ints = new Integer[SIZE];
        Integer[] array = q.toArray(ints);
        assertSame(ints, array);
        for (int i = 0; i < ints.length; i++)
            assertSame(ints[i], q.poll());
    }

    /**
     * toArray(null) throws NullPointerException
     */
    public void testToArray_NullArg() {
        ConcurrentLinkedQueue q = populatedQueue(SIZE);
        try {
            q.toArray(null);
            shouldThrow();
        } catch (NullPointerException success) {}
    }

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

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

    /**
     * iterator ordering is FIFO
     */
    public void testIteratorOrdering() {
        final ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
        q.add(one);
        q.add(two);
        q.add(three);

        int k = 0;
        for (Iterator it = q.iterator(); it.hasNext();) {
            assertEquals(++k, it.next());
        }

        assertEquals(3, k);
    }

    /**
     * Modifications do not cause iterators to fail
     */
    public void testWeaklyConsistentIteration() {
        final ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
        q.add(one);
        q.add(two);
        q.add(three);

        for (Iterator it = q.iterator(); it.hasNext();) {
            q.remove();
            it.next();
        }

        assertEquals("queue should be empty again", 0, q.size());
    }

    /**
     * iterator.remove removes current element
     */
    public void testIteratorRemove() {
        final ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
        q.add(one);
        q.add(two);
        q.add(three);
        Iterator it = q.iterator();
        it.next();
        it.remove();
        it = q.iterator();
        assertSame(it.next(), two);
        assertSame(it.next(), three);
        assertFalse(it.hasNext());
    }

    /**
     * toString contains toStrings of elements
     */
    public void testToString() {
        ConcurrentLinkedQueue q = populatedQueue(SIZE);
        String s = q.toString();
        for (int i = 0; i < SIZE; ++i) {
            assertTrue(s.contains(String.valueOf(i)));
        }
    }

    /**
     * A deserialized serialized queue has same elements in same order
     */
    public void testSerialization() throws Exception {
        ConcurrentLinkedQueue q = populatedQueue(SIZE);
        ByteArrayOutputStream bout = new ByteArrayOutputStream(10000);
        ObjectOutputStream out = new ObjectOutputStream(new BufferedOutputStream(bout));
        out.writeObject(q);
        out.close();

        ByteArrayInputStream bin = new ByteArrayInputStream(bout.toByteArray());
        ObjectInputStream in = new ObjectInputStream(new BufferedInputStream(bin));
        ConcurrentLinkedQueue r = (ConcurrentLinkedQueue)in.readObject();
        assertEquals(q.size(), r.size());
        while (!q.isEmpty())
            assertEquals(q.remove(), r.remove());
    }

}
Revision:	1.26
Committed:	Fri May 27 19:49:56 2011 UTC (13 years ago) by jsr166
Branch:	MAIN
Changes since 1.25:	+1 -3 lines
Log Message:	indexOf => contains
#	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.*;
11	import java.util.concurrent.*;
12	import java.io.*;
13
14	public class ConcurrentLinkedQueueTest extends JSR166TestCase {
15
16	public static void main(String[] args) {
17	junit.textui.TestRunner.run(suite());
18	}
19
20	public static Test suite() {
21	return new TestSuite(ConcurrentLinkedQueueTest.class);
22	}
23
24	/**
25	* Create a queue of given size containing consecutive
26	* Integers 0 ... n.
27	*/
28	private ConcurrentLinkedQueue<Integer> populatedQueue(int n) {
29	ConcurrentLinkedQueue<Integer> q = new ConcurrentLinkedQueue<Integer>();
30	assertTrue(q.isEmpty());
31	for (int i = 0; i < n; ++i)
32	assertTrue(q.offer(new Integer(i)));
33	assertFalse(q.isEmpty());
34	assertEquals(n, q.size());
35	return q;
36	}
37
38	/**
39	* new queue is empty
40	*/
41	public void testConstructor1() {
42	assertEquals(0, new ConcurrentLinkedQueue().size());
43	}
44
45	/**
46	* Initializing from null Collection throws NPE
47	*/
48	public void testConstructor3() {
49	try {
50	ConcurrentLinkedQueue q = new ConcurrentLinkedQueue((Collection)null);
51	shouldThrow();
52	} catch (NullPointerException success) {}
53	}
54
55	/**
56	* Initializing from Collection of null elements throws NPE
57	*/
58	public void testConstructor4() {
59	try {
60	Integer[] ints = new Integer[SIZE];
61	ConcurrentLinkedQueue q = new ConcurrentLinkedQueue(Arrays.asList(ints));
62	shouldThrow();
63	} catch (NullPointerException success) {}
64	}
65
66	/**
67	* Initializing from Collection with some null elements throws NPE
68	*/
69	public void testConstructor5() {
70	try {
71	Integer[] ints = new Integer[SIZE];
72	for (int i = 0; i < SIZE-1; ++i)
73	ints[i] = new Integer(i);
74	ConcurrentLinkedQueue q = new ConcurrentLinkedQueue(Arrays.asList(ints));
75	shouldThrow();
76	} catch (NullPointerException success) {}
77	}
78
79	/**
80	* Queue contains all elements of collection used to initialize
81	*/
82	public void testConstructor6() {
83	Integer[] ints = new Integer[SIZE];
84	for (int i = 0; i < SIZE; ++i)
85	ints[i] = new Integer(i);
86	ConcurrentLinkedQueue q = new ConcurrentLinkedQueue(Arrays.asList(ints));
87	for (int i = 0; i < SIZE; ++i)
88	assertEquals(ints[i], q.poll());
89	}
90
91	/**
92	* isEmpty is true before add, false after
93	*/
94	public void testEmpty() {
95	ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
96	assertTrue(q.isEmpty());
97	q.add(one);
98	assertFalse(q.isEmpty());
99	q.add(two);
100	q.remove();
101	q.remove();
102	assertTrue(q.isEmpty());
103	}
104
105	/**
106	* size changes when elements added and removed
107	*/
108	public void testSize() {
109	ConcurrentLinkedQueue q = populatedQueue(SIZE);
110	for (int i = 0; i < SIZE; ++i) {
111	assertEquals(SIZE-i, q.size());
112	q.remove();
113	}
114	for (int i = 0; i < SIZE; ++i) {
115	assertEquals(i, q.size());
116	q.add(new Integer(i));
117	}
118	}
119
120	/**
121	* offer(null) throws NPE
122	*/
123	public void testOfferNull() {
124	try {
125	ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
126	q.offer(null);
127	shouldThrow();
128	} catch (NullPointerException success) {}
129	}
130
131	/**
132	* add(null) throws NPE
133	*/
134	public void testAddNull() {
135	try {
136	ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
137	q.add(null);
138	shouldThrow();
139	} catch (NullPointerException success) {}
140	}
141
142	/**
143	* Offer returns true
144	*/
145	public void testOffer() {
146	ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
147	assertTrue(q.offer(zero));
148	assertTrue(q.offer(one));
149	}
150
151	/**
152	* add returns true
153	*/
154	public void testAdd() {
155	ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
156	for (int i = 0; i < SIZE; ++i) {
157	assertEquals(i, q.size());
158	assertTrue(q.add(new Integer(i)));
159	}
160	}
161
162	/**
163	* addAll(null) throws NPE
164	*/
165	public void testAddAll1() {
166	try {
167	ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
168	q.addAll(null);
169	shouldThrow();
170	} catch (NullPointerException success) {}
171	}
172
173	/**
174	* addAll(this) throws IAE
175	*/
176	public void testAddAllSelf() {
177	try {
178	ConcurrentLinkedQueue q = populatedQueue(SIZE);
179	q.addAll(q);
180	shouldThrow();
181	} catch (IllegalArgumentException success) {}
182	}
183
184	/**
185	* addAll of a collection with null elements throws NPE
186	*/
187	public void testAddAll2() {
188	try {
189	ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
190	Integer[] ints = new Integer[SIZE];
191	q.addAll(Arrays.asList(ints));
192	shouldThrow();
193	} catch (NullPointerException success) {}
194	}
195
196	/**
197	* addAll of a collection with any null elements throws NPE after
198	* possibly adding some elements
199	*/
200	public void testAddAll3() {
201	try {
202	ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
203	Integer[] ints = new Integer[SIZE];
204	for (int i = 0; i < SIZE-1; ++i)
205	ints[i] = new Integer(i);
206	q.addAll(Arrays.asList(ints));
207	shouldThrow();
208	} catch (NullPointerException success) {}
209	}
210
211	/**
212	* Queue contains all elements, in traversal order, of successful addAll
213	*/
214	public void testAddAll5() {
215	Integer[] empty = new Integer[0];
216	Integer[] ints = new Integer[SIZE];
217	for (int i = 0; i < SIZE; ++i)
218	ints[i] = new Integer(i);
219	ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
220	assertFalse(q.addAll(Arrays.asList(empty)));
221	assertTrue(q.addAll(Arrays.asList(ints)));
222	for (int i = 0; i < SIZE; ++i)
223	assertEquals(ints[i], q.poll());
224	}
225
226	/**
227	* poll succeeds unless empty
228	*/
229	public void testPoll() {
230	ConcurrentLinkedQueue q = populatedQueue(SIZE);
231	for (int i = 0; i < SIZE; ++i) {
232	assertEquals(i, q.poll());
233	}
234	assertNull(q.poll());
235	}
236
237	/**
238	* peek returns next element, or null if empty
239	*/
240	public void testPeek() {
241	ConcurrentLinkedQueue q = populatedQueue(SIZE);
242	for (int i = 0; i < SIZE; ++i) {
243	assertEquals(i, q.peek());
244	assertEquals(i, q.poll());
245	assertTrue(q.peek() == null \|\|
246	!q.peek().equals(i));
247	}
248	assertNull(q.peek());
249	}
250
251	/**
252	* element returns next element, or throws NSEE if empty
253	*/
254	public void testElement() {
255	ConcurrentLinkedQueue q = populatedQueue(SIZE);
256	for (int i = 0; i < SIZE; ++i) {
257	assertEquals(i, q.element());
258	assertEquals(i, q.poll());
259	}
260	try {
261	q.element();
262	shouldThrow();
263	} catch (NoSuchElementException success) {}
264	}
265
266	/**
267	* remove removes next element, or throws NSEE if empty
268	*/
269	public void testRemove() {
270	ConcurrentLinkedQueue q = populatedQueue(SIZE);
271	for (int i = 0; i < SIZE; ++i) {
272	assertEquals(i, q.remove());
273	}
274	try {
275	q.remove();
276	shouldThrow();
277	} catch (NoSuchElementException success) {}
278	}
279
280	/**
281	* remove(x) removes x and returns true if present
282	*/
283	public void testRemoveElement() {
284	ConcurrentLinkedQueue q = populatedQueue(SIZE);
285	for (int i = 1; i < SIZE; i+=2) {
286	assertTrue(q.contains(i));
287	assertTrue(q.remove(i));
288	assertFalse(q.contains(i));
289	assertTrue(q.contains(i-1));
290	}
291	for (int i = 0; i < SIZE; i+=2) {
292	assertTrue(q.contains(i));
293	assertTrue(q.remove(i));
294	assertFalse(q.contains(i));
295	assertFalse(q.remove(i+1));
296	assertFalse(q.contains(i+1));
297	}
298	assertTrue(q.isEmpty());
299	}
300
301	/**
302	* contains(x) reports true when elements added but not yet removed
303	*/
304	public void testContains() {
305	ConcurrentLinkedQueue q = populatedQueue(SIZE);
306	for (int i = 0; i < SIZE; ++i) {
307	assertTrue(q.contains(new Integer(i)));
308	q.poll();
309	assertFalse(q.contains(new Integer(i)));
310	}
311	}
312
313	/**
314	* clear removes all elements
315	*/
316	public void testClear() {
317	ConcurrentLinkedQueue q = populatedQueue(SIZE);
318	q.clear();
319	assertTrue(q.isEmpty());
320	assertEquals(0, q.size());
321	q.add(one);
322	assertFalse(q.isEmpty());
323	q.clear();
324	assertTrue(q.isEmpty());
325	}
326
327	/**
328	* containsAll(c) is true when c contains a subset of elements
329	*/
330	public void testContainsAll() {
331	ConcurrentLinkedQueue q = populatedQueue(SIZE);
332	ConcurrentLinkedQueue p = new ConcurrentLinkedQueue();
333	for (int i = 0; i < SIZE; ++i) {
334	assertTrue(q.containsAll(p));
335	assertFalse(p.containsAll(q));
336	p.add(new Integer(i));
337	}
338	assertTrue(p.containsAll(q));
339	}
340
341	/**
342	* retainAll(c) retains only those elements of c and reports true if change
343	*/
344	public void testRetainAll() {
345	ConcurrentLinkedQueue q = populatedQueue(SIZE);
346	ConcurrentLinkedQueue p = populatedQueue(SIZE);
347	for (int i = 0; i < SIZE; ++i) {
348	boolean changed = q.retainAll(p);
349	if (i == 0)
350	assertFalse(changed);
351	else
352	assertTrue(changed);
353
354	assertTrue(q.containsAll(p));
355	assertEquals(SIZE-i, q.size());
356	p.remove();
357	}
358	}
359
360	/**
361	* removeAll(c) removes only those elements of c and reports true if changed
362	*/
363	public void testRemoveAll() {
364	for (int i = 1; i < SIZE; ++i) {
365	ConcurrentLinkedQueue q = populatedQueue(SIZE);
366	ConcurrentLinkedQueue p = populatedQueue(i);
367	assertTrue(q.removeAll(p));
368	assertEquals(SIZE-i, q.size());
369	for (int j = 0; j < i; ++j) {
370	Integer I = (Integer)(p.remove());
371	assertFalse(q.contains(I));
372	}
373	}
374	}
375
376	/**
377	* toArray contains all elements in FIFO order
378	*/
379	public void testToArray() {
380	ConcurrentLinkedQueue q = populatedQueue(SIZE);
381	Object[] o = q.toArray();
382	for (int i = 0; i < o.length; i++)
383	assertSame(o[i], q.poll());
384	}
385
386	/**
387	* toArray(a) contains all elements in FIFO order
388	*/
389	public void testToArray2() {
390	ConcurrentLinkedQueue<Integer> q = populatedQueue(SIZE);
391	Integer[] ints = new Integer[SIZE];
392	Integer[] array = q.toArray(ints);
393	assertSame(ints, array);
394	for (int i = 0; i < ints.length; i++)
395	assertSame(ints[i], q.poll());
396	}
397
398	/**
399	* toArray(null) throws NullPointerException
400	*/
401	public void testToArray_NullArg() {
402	ConcurrentLinkedQueue q = populatedQueue(SIZE);
403	try {
404	q.toArray(null);
405	shouldThrow();
406	} catch (NullPointerException success) {}
407	}
408
409	/**
410	* toArray(incompatible array type) throws ArrayStoreException
411	*/
412	public void testToArray1_BadArg() {
413	ConcurrentLinkedQueue q = populatedQueue(SIZE);
414	try {
415	q.toArray(new String[10]);
416	shouldThrow();
417	} catch (ArrayStoreException success) {}
418	}
419
420	/**
421	* iterator iterates through all elements
422	*/
423	public void testIterator() {
424	ConcurrentLinkedQueue q = populatedQueue(SIZE);
425	int i = 0;
426	Iterator it = q.iterator();
427	while (it.hasNext()) {
428	assertTrue(q.contains(it.next()));
429	++i;
430	}
431	assertEquals(i, SIZE);
432	}
433
434	/**
435	* iterator ordering is FIFO
436	*/
437	public void testIteratorOrdering() {
438	final ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
439	q.add(one);
440	q.add(two);
441	q.add(three);
442
443	int k = 0;
444	for (Iterator it = q.iterator(); it.hasNext();) {
445	assertEquals(++k, it.next());
446	}
447
448	assertEquals(3, k);
449	}
450
451	/**
452	* Modifications do not cause iterators to fail
453	*/
454	public void testWeaklyConsistentIteration() {
455	final ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
456	q.add(one);
457	q.add(two);
458	q.add(three);
459
460	for (Iterator it = q.iterator(); it.hasNext();) {
461	q.remove();
462	it.next();
463	}
464
465	assertEquals("queue should be empty again", 0, q.size());
466	}
467
468	/**
469	* iterator.remove removes current element
470	*/
471	public void testIteratorRemove() {
472	final ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
473	q.add(one);
474	q.add(two);
475	q.add(three);
476	Iterator it = q.iterator();
477	it.next();
478	it.remove();
479	it = q.iterator();
480	assertSame(it.next(), two);
481	assertSame(it.next(), three);
482	assertFalse(it.hasNext());
483	}
484
485	/**
486	* toString contains toStrings of elements
487	*/
488	public void testToString() {
489	ConcurrentLinkedQueue q = populatedQueue(SIZE);
490	String s = q.toString();
491	for (int i = 0; i < SIZE; ++i) {
492	assertTrue(s.contains(String.valueOf(i)));
493	}
494	}
495
496	/**
497	* A deserialized serialized queue has same elements in same order
498	*/
499	public void testSerialization() throws Exception {
500	ConcurrentLinkedQueue q = populatedQueue(SIZE);
501	ByteArrayOutputStream bout = new ByteArrayOutputStream(10000);
502	ObjectOutputStream out = new ObjectOutputStream(new BufferedOutputStream(bout));
503	out.writeObject(q);
504	out.close();
505
506	ByteArrayInputStream bin = new ByteArrayInputStream(bout.toByteArray());
507	ObjectInputStream in = new ObjectInputStream(new BufferedInputStream(bin));
508	ConcurrentLinkedQueue r = (ConcurrentLinkedQueue)in.readObject();
509	assertEquals(q.size(), r.size());
510	while (!q.isEmpty())
511	assertEquals(q.remove(), r.remove());
512	}
513
514	}