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/licenses/publicdomain
 * 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 populatedQueue(int n) {
        ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
        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() {
        try {
            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());
        }
        finally {}
    }

    /**
     * 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() {
        try {
            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());
        }
        finally {}
    }

    /**
     * poll succeeds unless empty
     */
    public void testPoll() {
        ConcurrentLinkedQueue q = populatedQueue(SIZE);
        for (int i = 0; i < SIZE; ++i) {
            assertEquals(i, ((Integer)q.poll()).intValue());
        }
        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, ((Integer)q.peek()).intValue());
            q.poll();
            assertTrue(q.peek() == null ||
                       i != ((Integer)q.peek()).intValue());
        }
        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, ((Integer)q.element()).intValue());
            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, ((Integer)q.remove()).intValue());
        }
        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.remove(new Integer(i)));
        }
        for (int i = 0; i < SIZE; i+=2) {
            assertTrue(q.remove(new Integer(i)));
            assertFalse(q.remove(new Integer(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
     */
    public void testToArray() {
        ConcurrentLinkedQueue q = populatedQueue(SIZE);
        Object[] o = q.toArray();
        Arrays.sort(o);
        for (int i = 0; i < o.length; i++)
            assertEquals(o[i], q.poll());
    }

    /**
     *  toArray(a) contains all elements
     */
    public void testToArray2() {
        ConcurrentLinkedQueue q = populatedQueue(SIZE);
        Integer[] ints = new Integer[SIZE];
        ints = (Integer[])q.toArray(ints);
        Arrays.sort(ints);
        for (int i = 0; i < ints.length; i++)
            assertEquals(ints[i], q.poll());
    }

    /**
     * toArray(null) throws NPE
     */
    public void testToArray_BadArg() {
        try {
            ConcurrentLinkedQueue q = populatedQueue(SIZE);
            Object o[] = q.toArray(null);
            shouldThrow();
        } catch (NullPointerException success) {}
    }

    /**
     * toArray with incompatible array type throws ArrayStoreException
     */
    public void testToArray1_BadArg() {
        try {
            ConcurrentLinkedQueue q = populatedQueue(SIZE);
            Object o[] = 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();) {
            int i = ((Integer)(it.next())).intValue();
            assertEquals(++k, i);
        }

        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();
        assertEquals(it.next(), two);
        assertEquals(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.indexOf(String.valueOf(i)) >= 0);
        }
    }

    /**
     * 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:	1.13
Committed:	Sat Nov 21 10:25:05 2009 UTC (14 years, 6 months ago) by jsr166
Branch:	MAIN
Changes since 1.12:	+25 -42 lines
Log Message:	improve exception handling
#	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/licenses/publicdomain
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 populatedQueue(int n) {
29	ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
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	}
77	catch (NullPointerException success) {}
78	}
79
80	/**
81	* Queue contains all elements of collection used to initialize
82	*/
83	public void testConstructor6() {
84	try {
85	Integer[] ints = new Integer[SIZE];
86	for (int i = 0; i < SIZE; ++i)
87	ints[i] = new Integer(i);
88	ConcurrentLinkedQueue q = new ConcurrentLinkedQueue(Arrays.asList(ints));
89	for (int i = 0; i < SIZE; ++i)
90	assertEquals(ints[i], q.poll());
91	}
92	finally {}
93	}
94
95	/**
96	* isEmpty is true before add, false after
97	*/
98	public void testEmpty() {
99	ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
100	assertTrue(q.isEmpty());
101	q.add(one);
102	assertFalse(q.isEmpty());
103	q.add(two);
104	q.remove();
105	q.remove();
106	assertTrue(q.isEmpty());
107	}
108
109	/**
110	* size changes when elements added and removed
111	*/
112	public void testSize() {
113	ConcurrentLinkedQueue q = populatedQueue(SIZE);
114	for (int i = 0; i < SIZE; ++i) {
115	assertEquals(SIZE-i, q.size());
116	q.remove();
117	}
118	for (int i = 0; i < SIZE; ++i) {
119	assertEquals(i, q.size());
120	q.add(new Integer(i));
121	}
122	}
123
124	/**
125	* offer(null) throws NPE
126	*/
127	public void testOfferNull() {
128	try {
129	ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
130	q.offer(null);
131	shouldThrow();
132	} catch (NullPointerException success) {}
133	}
134
135	/**
136	* add(null) throws NPE
137	*/
138	public void testAddNull() {
139	try {
140	ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
141	q.add(null);
142	shouldThrow();
143	} catch (NullPointerException success) {}
144	}
145
146
147	/**
148	* Offer returns true
149	*/
150	public void testOffer() {
151	ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
152	assertTrue(q.offer(zero));
153	assertTrue(q.offer(one));
154	}
155
156	/**
157	* add returns true
158	*/
159	public void testAdd() {
160	ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
161	for (int i = 0; i < SIZE; ++i) {
162	assertEquals(i, q.size());
163	assertTrue(q.add(new Integer(i)));
164	}
165	}
166
167	/**
168	* addAll(null) throws NPE
169	*/
170	public void testAddAll1() {
171	try {
172	ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
173	q.addAll(null);
174	shouldThrow();
175	} catch (NullPointerException success) {}
176	}
177
178	/**
179	* addAll(this) throws IAE
180	*/
181	public void testAddAllSelf() {
182	try {
183	ConcurrentLinkedQueue q = populatedQueue(SIZE);
184	q.addAll(q);
185	shouldThrow();
186	} catch (IllegalArgumentException success) {}
187	}
188
189	/**
190	* addAll of a collection with null elements throws NPE
191	*/
192	public void testAddAll2() {
193	try {
194	ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
195	Integer[] ints = new Integer[SIZE];
196	q.addAll(Arrays.asList(ints));
197	shouldThrow();
198	} catch (NullPointerException success) {}
199	}
200	/**
201	* addAll of a collection with any null elements throws NPE after
202	* possibly adding some elements
203	*/
204	public void testAddAll3() {
205	try {
206	ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
207	Integer[] ints = new Integer[SIZE];
208	for (int i = 0; i < SIZE-1; ++i)
209	ints[i] = new Integer(i);
210	q.addAll(Arrays.asList(ints));
211	shouldThrow();
212	} catch (NullPointerException success) {}
213	}
214
215	/**
216	* Queue contains all elements, in traversal order, of successful addAll
217	*/
218	public void testAddAll5() {
219	try {
220	Integer[] empty = new Integer[0];
221	Integer[] ints = new Integer[SIZE];
222	for (int i = 0; i < SIZE; ++i)
223	ints[i] = new Integer(i);
224	ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
225	assertFalse(q.addAll(Arrays.asList(empty)));
226	assertTrue(q.addAll(Arrays.asList(ints)));
227	for (int i = 0; i < SIZE; ++i)
228	assertEquals(ints[i], q.poll());
229	}
230	finally {}
231	}
232
233	/**
234	* poll succeeds unless empty
235	*/
236	public void testPoll() {
237	ConcurrentLinkedQueue q = populatedQueue(SIZE);
238	for (int i = 0; i < SIZE; ++i) {
239	assertEquals(i, ((Integer)q.poll()).intValue());
240	}
241	assertNull(q.poll());
242	}
243
244	/**
245	* peek returns next element, or null if empty
246	*/
247	public void testPeek() {
248	ConcurrentLinkedQueue q = populatedQueue(SIZE);
249	for (int i = 0; i < SIZE; ++i) {
250	assertEquals(i, ((Integer)q.peek()).intValue());
251	q.poll();
252	assertTrue(q.peek() == null \|\|
253	i != ((Integer)q.peek()).intValue());
254	}
255	assertNull(q.peek());
256	}
257
258	/**
259	* element returns next element, or throws NSEE if empty
260	*/
261	public void testElement() {
262	ConcurrentLinkedQueue q = populatedQueue(SIZE);
263	for (int i = 0; i < SIZE; ++i) {
264	assertEquals(i, ((Integer)q.element()).intValue());
265	q.poll();
266	}
267	try {
268	q.element();
269	shouldThrow();
270	} catch (NoSuchElementException success) {}
271	}
272
273	/**
274	* remove removes next element, or throws NSEE if empty
275	*/
276	public void testRemove() {
277	ConcurrentLinkedQueue q = populatedQueue(SIZE);
278	for (int i = 0; i < SIZE; ++i) {
279	assertEquals(i, ((Integer)q.remove()).intValue());
280	}
281	try {
282	q.remove();
283	shouldThrow();
284	} catch (NoSuchElementException success) {}
285	}
286
287	/**
288	* remove(x) removes x and returns true if present
289	*/
290	public void testRemoveElement() {
291	ConcurrentLinkedQueue q = populatedQueue(SIZE);
292	for (int i = 1; i < SIZE; i+=2) {
293	assertTrue(q.remove(new Integer(i)));
294	}
295	for (int i = 0; i < SIZE; i+=2) {
296	assertTrue(q.remove(new Integer(i)));
297	assertFalse(q.remove(new Integer(i+1)));
298	}
299	assertTrue(q.isEmpty());
300	}
301
302	/**
303	* contains(x) reports true when elements added but not yet removed
304	*/
305	public void testContains() {
306	ConcurrentLinkedQueue q = populatedQueue(SIZE);
307	for (int i = 0; i < SIZE; ++i) {
308	assertTrue(q.contains(new Integer(i)));
309	q.poll();
310	assertFalse(q.contains(new Integer(i)));
311	}
312	}
313
314	/**
315	* clear removes all elements
316	*/
317	public void testClear() {
318	ConcurrentLinkedQueue q = populatedQueue(SIZE);
319	q.clear();
320	assertTrue(q.isEmpty());
321	assertEquals(0, q.size());
322	q.add(one);
323	assertFalse(q.isEmpty());
324	q.clear();
325	assertTrue(q.isEmpty());
326	}
327
328	/**
329	* containsAll(c) is true when c contains a subset of elements
330	*/
331	public void testContainsAll() {
332	ConcurrentLinkedQueue q = populatedQueue(SIZE);
333	ConcurrentLinkedQueue p = new ConcurrentLinkedQueue();
334	for (int i = 0; i < SIZE; ++i) {
335	assertTrue(q.containsAll(p));
336	assertFalse(p.containsAll(q));
337	p.add(new Integer(i));
338	}
339	assertTrue(p.containsAll(q));
340	}
341
342	/**
343	* retainAll(c) retains only those elements of c and reports true if change
344	*/
345	public void testRetainAll() {
346	ConcurrentLinkedQueue q = populatedQueue(SIZE);
347	ConcurrentLinkedQueue p = populatedQueue(SIZE);
348	for (int i = 0; i < SIZE; ++i) {
349	boolean changed = q.retainAll(p);
350	if (i == 0)
351	assertFalse(changed);
352	else
353	assertTrue(changed);
354
355	assertTrue(q.containsAll(p));
356	assertEquals(SIZE-i, q.size());
357	p.remove();
358	}
359	}
360
361	/**
362	* removeAll(c) removes only those elements of c and reports true if changed
363	*/
364	public void testRemoveAll() {
365	for (int i = 1; i < SIZE; ++i) {
366	ConcurrentLinkedQueue q = populatedQueue(SIZE);
367	ConcurrentLinkedQueue p = populatedQueue(i);
368	assertTrue(q.removeAll(p));
369	assertEquals(SIZE-i, q.size());
370	for (int j = 0; j < i; ++j) {
371	Integer I = (Integer)(p.remove());
372	assertFalse(q.contains(I));
373	}
374	}
375	}
376
377	/**
378	* toArray contains all elements
379	*/
380	public void testToArray() {
381	ConcurrentLinkedQueue q = populatedQueue(SIZE);
382	Object[] o = q.toArray();
383	Arrays.sort(o);
384	for (int i = 0; i < o.length; i++)
385	assertEquals(o[i], q.poll());
386	}
387
388	/**
389	* toArray(a) contains all elements
390	*/
391	public void testToArray2() {
392	ConcurrentLinkedQueue q = populatedQueue(SIZE);
393	Integer[] ints = new Integer[SIZE];
394	ints = (Integer[])q.toArray(ints);
395	Arrays.sort(ints);
396	for (int i = 0; i < ints.length; i++)
397	assertEquals(ints[i], q.poll());
398	}
399
400	/**
401	* toArray(null) throws NPE
402	*/
403	public void testToArray_BadArg() {
404	try {
405	ConcurrentLinkedQueue q = populatedQueue(SIZE);
406	Object o[] = q.toArray(null);
407	shouldThrow();
408	} catch (NullPointerException success) {}
409	}
410
411	/**
412	* toArray with incompatible array type throws ArrayStoreException
413	*/
414	public void testToArray1_BadArg() {
415	try {
416	ConcurrentLinkedQueue q = populatedQueue(SIZE);
417	Object o[] = q.toArray(new String[10] );
418	shouldThrow();
419	} catch (ArrayStoreException success) {}
420	}
421
422	/**
423	* iterator iterates through all elements
424	*/
425	public void testIterator() {
426	ConcurrentLinkedQueue q = populatedQueue(SIZE);
427	int i = 0;
428	Iterator it = q.iterator();
429	while (it.hasNext()) {
430	assertTrue(q.contains(it.next()));
431	++i;
432	}
433	assertEquals(i, SIZE);
434	}
435
436	/**
437	* iterator ordering is FIFO
438	*/
439	public void testIteratorOrdering() {
440	final ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
441	q.add(one);
442	q.add(two);
443	q.add(three);
444
445	int k = 0;
446	for (Iterator it = q.iterator(); it.hasNext();) {
447	int i = ((Integer)(it.next())).intValue();
448	assertEquals(++k, i);
449	}
450
451	assertEquals(3, k);
452	}
453
454	/**
455	* Modifications do not cause iterators to fail
456	*/
457	public void testWeaklyConsistentIteration () {
458	final ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
459	q.add(one);
460	q.add(two);
461	q.add(three);
462
463	for (Iterator it = q.iterator(); it.hasNext();) {
464	q.remove();
465	it.next();
466	}
467
468	assertEquals("queue should be empty again", 0, q.size());
469	}
470
471	/**
472	* iterator.remove removes current element
473	*/
474	public void testIteratorRemove () {
475	final ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
476	q.add(one);
477	q.add(two);
478	q.add(three);
479	Iterator it = q.iterator();
480	it.next();
481	it.remove();
482	it = q.iterator();
483	assertEquals(it.next(), two);
484	assertEquals(it.next(), three);
485	assertFalse(it.hasNext());
486	}
487
488
489	/**
490	* toString contains toStrings of elements
491	*/
492	public void testToString() {
493	ConcurrentLinkedQueue q = populatedQueue(SIZE);
494	String s = q.toString();
495	for (int i = 0; i < SIZE; ++i) {
496	assertTrue(s.indexOf(String.valueOf(i)) >= 0);
497	}
498	}
499
500	/**
501	* A deserialized serialized queue has same elements in same order
502	*/
503	public void testSerialization() throws Exception {
504	ConcurrentLinkedQueue q = populatedQueue(SIZE);
505	ByteArrayOutputStream bout = new ByteArrayOutputStream(10000);
506	ObjectOutputStream out = new ObjectOutputStream(new BufferedOutputStream(bout));
507	out.writeObject(q);
508	out.close();
509
510	ByteArrayInputStream bin = new ByteArrayInputStream(bout.toByteArray());
511	ObjectInputStream in = new ObjectInputStream(new BufferedInputStream(bin));
512	ConcurrentLinkedQueue r = (ConcurrentLinkedQueue)in.readObject();
513	assertEquals(q.size(), r.size());
514	while (!q.isEmpty())
515	assertEquals(q.remove(), r.remove());
516	}
517
518	}