test/tck/ConcurrentLinkedQueueTest.java

/*
 * Written by members of JCP JSR-166 Expert Group and released to the
 * public domain. Use, modify, and redistribute this code in any way
 * without acknowledgement. Other contributors include Andrew Wright,
 * Jeffrey Hayes, Pat Fischer, 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 incompatable array type throws CCE
     */
    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);

        try {
            for (Iterator it = q.iterator(); it.hasNext();) {
                q.remove();
                it.next();
            }
        }
        catch (ConcurrentModificationException e) {
            shouldThrow();
        }

        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() {
        ConcurrentLinkedQueue q = populatedQueue(SIZE);
        try {
            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());
        } catch(Exception e){
            unexpectedException();
        }
    }

}
Revision:	1.5
Committed:	Sun Oct 5 23:00:40 2003 UTC (20 years, 7 months ago) by dl
Branch:	MAIN
CVS Tags:	JSR166_NOV3_FREEZE, JSR166_DEC9_PRE_ES_SUBMIT, JSR166_DEC9_POST_ES_SUBMIT
Changes since 1.4:	+80 -32 lines
Log Message:	Added tests and documentation
#	User	Rev	Content
1	dl	1.1	/*
2			* Written by members of JCP JSR-166 Expert Group and released to the
3			* public domain. Use, modify, and redistribute this code in any way
4			* without acknowledgement. Other contributors include Andrew Wright,
5			* Jeffrey Hayes, Pat Fischer, Mike Judd.
6			*/
7
8			import junit.framework.*;
9			import java.util.*;
10			import java.util.concurrent.*;
11	dl	1.2	import java.io.*;
12	dl	1.1
13	dl	1.3	public class ConcurrentLinkedQueueTest extends JSR166TestCase {
14	dl	1.1
15			public static void main(String[] args) {
16			junit.textui.TestRunner.run (suite());
17			}
18
19			public static Test suite() {
20			return new TestSuite(ConcurrentLinkedQueueTest.class);
21			}
22
23			/**
24			* Create a queue of given size containing consecutive
25			* Integers 0 ... n.
26			*/
27	dl	1.3	private ConcurrentLinkedQueue populatedQueue(int n) {
28	dl	1.1	ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
29			assertTrue(q.isEmpty());
30			for(int i = 0; i < n; ++i)
31			assertTrue(q.offer(new Integer(i)));
32			assertFalse(q.isEmpty());
33			assertEquals(n, q.size());
34			return q;
35			}
36
37	dl	1.4	/**
38	dl	1.5	* new queue is empty
39	dl	1.4	*/
40			public void testConstructor1() {
41	dl	1.1	assertEquals(0, new ConcurrentLinkedQueue().size());
42			}
43
44	dl	1.4	/**
45	dl	1.5	* Initializing from null Collection throws NPE
46	dl	1.4	*/
47	dl	1.1	public void testConstructor3() {
48			try {
49			ConcurrentLinkedQueue q = new ConcurrentLinkedQueue((Collection)null);
50	dl	1.4	shouldThrow();
51	dl	1.1	}
52			catch (NullPointerException success) {}
53			}
54
55	dl	1.4	/**
56	dl	1.5	* Initializing from Collection of null elements throws NPE
57	dl	1.4	*/
58			public void testConstructor4() {
59	dl	1.1	try {
60	dl	1.3	Integer[] ints = new Integer[SIZE];
61	dl	1.1	ConcurrentLinkedQueue q = new ConcurrentLinkedQueue(Arrays.asList(ints));
62	dl	1.4	shouldThrow();
63	dl	1.1	}
64			catch (NullPointerException success) {}
65			}
66
67	dl	1.4	/**
68	dl	1.5	* Initializing from Collection with some null elements throws NPE
69	dl	1.4	*/
70			public void testConstructor5() {
71	dl	1.1	try {
72	dl	1.3	Integer[] ints = new Integer[SIZE];
73			for (int i = 0; i < SIZE-1; ++i)
74	dl	1.1	ints[i] = new Integer(i);
75			ConcurrentLinkedQueue q = new ConcurrentLinkedQueue(Arrays.asList(ints));
76	dl	1.4	shouldThrow();
77	dl	1.1	}
78			catch (NullPointerException success) {}
79			}
80
81	dl	1.4	/**
82	dl	1.5	* Queue contains all elements of collection used to initialize
83	dl	1.4	*/
84			public void testConstructor6() {
85	dl	1.1	try {
86	dl	1.3	Integer[] ints = new Integer[SIZE];
87			for (int i = 0; i < SIZE; ++i)
88	dl	1.1	ints[i] = new Integer(i);
89			ConcurrentLinkedQueue q = new ConcurrentLinkedQueue(Arrays.asList(ints));
90	dl	1.3	for (int i = 0; i < SIZE; ++i)
91	dl	1.1	assertEquals(ints[i], q.poll());
92			}
93			finally {}
94			}
95
96	dl	1.4	/**
97	dl	1.5	* isEmpty is true before add, false after
98	dl	1.4	*/
99	dl	1.1	public void testEmpty() {
100			ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
101			assertTrue(q.isEmpty());
102	dl	1.3	q.add(one);
103	dl	1.1	assertFalse(q.isEmpty());
104	dl	1.3	q.add(two);
105	dl	1.1	q.remove();
106			q.remove();
107			assertTrue(q.isEmpty());
108			}
109
110	dl	1.4	/**
111	dl	1.5	* size changes when elements added and removed
112	dl	1.4	*/
113	dl	1.1	public void testSize() {
114	dl	1.3	ConcurrentLinkedQueue q = populatedQueue(SIZE);
115			for (int i = 0; i < SIZE; ++i) {
116			assertEquals(SIZE-i, q.size());
117	dl	1.1	q.remove();
118			}
119	dl	1.3	for (int i = 0; i < SIZE; ++i) {
120	dl	1.1	assertEquals(i, q.size());
121			q.add(new Integer(i));
122			}
123			}
124
125	dl	1.4	/**
126	dl	1.5	* offer(null) throws NPE
127	dl	1.4	*/
128			public void testOfferNull() {
129	dl	1.1	try {
130			ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
131			q.offer(null);
132	dl	1.4	shouldThrow();
133	dl	1.1	} catch (NullPointerException success) { }
134			}
135
136	dl	1.4	/**
137	dl	1.5	* add(null) throws NPE
138			*/
139			public void testAddNull() {
140			try {
141			ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
142			q.add(null);
143			shouldThrow();
144			} catch (NullPointerException success) { }
145			}
146
147
148			/**
149			* Offer returns true
150	dl	1.4	*/
151	dl	1.1	public void testOffer() {
152			ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
153	dl	1.3	assertTrue(q.offer(zero));
154			assertTrue(q.offer(one));
155	dl	1.1	}
156
157	dl	1.4	/**
158	dl	1.5	* add returns true
159	dl	1.4	*/
160			public void testAdd() {
161	dl	1.1	ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
162	dl	1.3	for (int i = 0; i < SIZE; ++i) {
163	dl	1.1	assertEquals(i, q.size());
164			assertTrue(q.add(new Integer(i)));
165			}
166			}
167
168	dl	1.4	/**
169	dl	1.5	* addAll(null) throws NPE
170	dl	1.4	*/
171			public void testAddAll1() {
172	dl	1.1	try {
173			ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
174			q.addAll(null);
175	dl	1.4	shouldThrow();
176	dl	1.1	}
177			catch (NullPointerException success) {}
178			}
179	dl	1.5
180			/**
181			* addAll(this) throws IAE
182			*/
183			public void testAddAllSelf() {
184			try {
185			ConcurrentLinkedQueue q = populatedQueue(SIZE);
186			q.addAll(q);
187			shouldThrow();
188			}
189			catch (IllegalArgumentException success) {}
190			}
191
192	dl	1.4	/**
193	dl	1.5	* addAll of a collection with null elements throws NPE
194	dl	1.4	*/
195			public void testAddAll2() {
196	dl	1.1	try {
197			ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
198	dl	1.3	Integer[] ints = new Integer[SIZE];
199	dl	1.1	q.addAll(Arrays.asList(ints));
200	dl	1.4	shouldThrow();
201	dl	1.1	}
202			catch (NullPointerException success) {}
203			}
204	dl	1.4	/**
205	dl	1.5	* addAll of a collection with any null elements throws NPE after
206			* possibly adding some elements
207	dl	1.4	*/
208			public void testAddAll3() {
209	dl	1.1	try {
210			ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
211	dl	1.3	Integer[] ints = new Integer[SIZE];
212			for (int i = 0; i < SIZE-1; ++i)
213	dl	1.1	ints[i] = new Integer(i);
214			q.addAll(Arrays.asList(ints));
215	dl	1.4	shouldThrow();
216	dl	1.1	}
217			catch (NullPointerException success) {}
218			}
219
220	dl	1.4	/**
221	dl	1.5	* Queue contains all elements, in traversal order, of successful addAll
222	dl	1.4	*/
223			public void testAddAll5() {
224	dl	1.1	try {
225			Integer[] empty = new Integer[0];
226	dl	1.3	Integer[] ints = new Integer[SIZE];
227			for (int i = 0; i < SIZE; ++i)
228	dl	1.1	ints[i] = new Integer(i);
229			ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
230			assertFalse(q.addAll(Arrays.asList(empty)));
231			assertTrue(q.addAll(Arrays.asList(ints)));
232	dl	1.3	for (int i = 0; i < SIZE; ++i)
233	dl	1.1	assertEquals(ints[i], q.poll());
234			}
235			finally {}
236			}
237
238	dl	1.4	/**
239	dl	1.5	* poll succeeds unless empty
240	dl	1.4	*/
241			public void testPoll() {
242	dl	1.3	ConcurrentLinkedQueue q = populatedQueue(SIZE);
243			for (int i = 0; i < SIZE; ++i) {
244	dl	1.1	assertEquals(i, ((Integer)q.poll()).intValue());
245			}
246			assertNull(q.poll());
247			}
248
249	dl	1.4	/**
250	dl	1.5	* peek returns next element, or null if empty
251	dl	1.4	*/
252			public void testPeek() {
253	dl	1.3	ConcurrentLinkedQueue q = populatedQueue(SIZE);
254			for (int i = 0; i < SIZE; ++i) {
255	dl	1.1	assertEquals(i, ((Integer)q.peek()).intValue());
256			q.poll();
257			assertTrue(q.peek() == null \|\|
258			i != ((Integer)q.peek()).intValue());
259			}
260			assertNull(q.peek());
261			}
262
263	dl	1.4	/**
264	dl	1.5	* element returns next element, or throws NSEE if empty
265	dl	1.4	*/
266			public void testElement() {
267	dl	1.3	ConcurrentLinkedQueue q = populatedQueue(SIZE);
268			for (int i = 0; i < SIZE; ++i) {
269	dl	1.1	assertEquals(i, ((Integer)q.element()).intValue());
270			q.poll();
271			}
272			try {
273			q.element();
274	dl	1.4	shouldThrow();
275	dl	1.1	}
276			catch (NoSuchElementException success) {}
277			}
278
279	dl	1.4	/**
280	dl	1.5	* remove removes next element, or throws NSEE if empty
281	dl	1.4	*/
282			public void testRemove() {
283	dl	1.3	ConcurrentLinkedQueue q = populatedQueue(SIZE);
284			for (int i = 0; i < SIZE; ++i) {
285	dl	1.1	assertEquals(i, ((Integer)q.remove()).intValue());
286			}
287			try {
288			q.remove();
289	dl	1.4	shouldThrow();
290	dl	1.1	} catch (NoSuchElementException success){
291			}
292			}
293
294	dl	1.4	/**
295	dl	1.5	* remove(x) removes x and returns true if present
296	dl	1.4	*/
297			public void testRemoveElement() {
298	dl	1.3	ConcurrentLinkedQueue q = populatedQueue(SIZE);
299			for (int i = 1; i < SIZE; i+=2) {
300	dl	1.1	assertTrue(q.remove(new Integer(i)));
301			}
302	dl	1.3	for (int i = 0; i < SIZE; i+=2) {
303	dl	1.1	assertTrue(q.remove(new Integer(i)));
304			assertFalse(q.remove(new Integer(i+1)));
305			}
306	dl	1.2	assertTrue(q.isEmpty());
307	dl	1.1	}
308
309	dl	1.4	/**
310	dl	1.5	* contains(x) reports true when elements added but not yet removed
311	dl	1.4	*/
312			public void testContains() {
313	dl	1.3	ConcurrentLinkedQueue q = populatedQueue(SIZE);
314			for (int i = 0; i < SIZE; ++i) {
315	dl	1.1	assertTrue(q.contains(new Integer(i)));
316			q.poll();
317			assertFalse(q.contains(new Integer(i)));
318			}
319			}
320
321	dl	1.4	/**
322	dl	1.5	* clear removes all elements
323	dl	1.4	*/
324			public void testClear() {
325	dl	1.3	ConcurrentLinkedQueue q = populatedQueue(SIZE);
326	dl	1.1	q.clear();
327			assertTrue(q.isEmpty());
328			assertEquals(0, q.size());
329	dl	1.3	q.add(one);
330	dl	1.1	assertFalse(q.isEmpty());
331			q.clear();
332			assertTrue(q.isEmpty());
333			}
334
335	dl	1.4	/**
336	dl	1.5	* containsAll(c) is true when c contains a subset of elements
337	dl	1.4	*/
338			public void testContainsAll() {
339	dl	1.3	ConcurrentLinkedQueue q = populatedQueue(SIZE);
340	dl	1.1	ConcurrentLinkedQueue p = new ConcurrentLinkedQueue();
341	dl	1.3	for (int i = 0; i < SIZE; ++i) {
342	dl	1.1	assertTrue(q.containsAll(p));
343			assertFalse(p.containsAll(q));
344			p.add(new Integer(i));
345			}
346			assertTrue(p.containsAll(q));
347			}
348
349	dl	1.4	/**
350	dl	1.5	* retainAll(c) retains only those elements of c and reports true if change
351	dl	1.4	*/
352			public void testRetainAll() {
353	dl	1.3	ConcurrentLinkedQueue q = populatedQueue(SIZE);
354			ConcurrentLinkedQueue p = populatedQueue(SIZE);
355			for (int i = 0; i < SIZE; ++i) {
356	dl	1.1	boolean changed = q.retainAll(p);
357			if (i == 0)
358			assertFalse(changed);
359			else
360			assertTrue(changed);
361
362			assertTrue(q.containsAll(p));
363	dl	1.3	assertEquals(SIZE-i, q.size());
364	dl	1.1	p.remove();
365			}
366			}
367
368	dl	1.4	/**
369	dl	1.5	* removeAll(c) removes only those elements of c and reports true if changed
370	dl	1.4	*/
371			public void testRemoveAll() {
372	dl	1.3	for (int i = 1; i < SIZE; ++i) {
373			ConcurrentLinkedQueue q = populatedQueue(SIZE);
374			ConcurrentLinkedQueue p = populatedQueue(i);
375	dl	1.1	assertTrue(q.removeAll(p));
376	dl	1.3	assertEquals(SIZE-i, q.size());
377	dl	1.1	for (int j = 0; j < i; ++j) {
378			Integer I = (Integer)(p.remove());
379			assertFalse(q.contains(I));
380			}
381			}
382			}
383
384	dl	1.4	/**
385	dl	1.5	* toArray contains all elements
386	dl	1.4	*/
387			public void testToArray() {
388	dl	1.3	ConcurrentLinkedQueue q = populatedQueue(SIZE);
389	dl	1.1	Object[] o = q.toArray();
390			Arrays.sort(o);
391			for(int i = 0; i < o.length; i++)
392			assertEquals(o[i], q.poll());
393			}
394
395	dl	1.4	/**
396	dl	1.5	* toArray(a) contains all elements
397	dl	1.4	*/
398			public void testToArray2() {
399	dl	1.3	ConcurrentLinkedQueue q = populatedQueue(SIZE);
400			Integer[] ints = new Integer[SIZE];
401	dl	1.1	ints = (Integer[])q.toArray(ints);
402			Arrays.sort(ints);
403			for(int i = 0; i < ints.length; i++)
404			assertEquals(ints[i], q.poll());
405			}
406	dl	1.5
407			/**
408			* toArray(null) throws NPE
409			*/
410			public void testToArray_BadArg() {
411			try {
412			ConcurrentLinkedQueue q = populatedQueue(SIZE);
413			Object o[] = q.toArray(null);
414			shouldThrow();
415			} catch(NullPointerException success){}
416			}
417
418			/**
419			* toArray with incompatable array type throws CCE
420			*/
421			public void testToArray1_BadArg() {
422			try {
423			ConcurrentLinkedQueue q = populatedQueue(SIZE);
424			Object o[] = q.toArray(new String[10] );
425			shouldThrow();
426			} catch(ArrayStoreException success){}
427			}
428	dl	1.1
429	dl	1.4	/**
430	dl	1.5	* iterator iterates through all elements
431	dl	1.4	*/
432			public void testIterator() {
433	dl	1.3	ConcurrentLinkedQueue q = populatedQueue(SIZE);
434	dl	1.1	int i = 0;
435			Iterator it = q.iterator();
436			while(it.hasNext()) {
437			assertTrue(q.contains(it.next()));
438			++i;
439			}
440	dl	1.3	assertEquals(i, SIZE);
441	dl	1.1	}
442
443	dl	1.4	/**
444	dl	1.5	* iterator ordering is FIFO
445	dl	1.4	*/
446	dl	1.1	public void testIteratorOrdering() {
447			final ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
448	dl	1.3	q.add(one);
449			q.add(two);
450			q.add(three);
451	dl	1.1
452			int k = 0;
453			for (Iterator it = q.iterator(); it.hasNext();) {
454			int i = ((Integer)(it.next())).intValue();
455	dl	1.4	assertEquals(++k, i);
456	dl	1.1	}
457
458	dl	1.4	assertEquals(3, k);
459	dl	1.1	}
460
461	dl	1.4	/**
462	dl	1.5	* Modifications do not cause iterators to fail
463	dl	1.4	*/
464	dl	1.1	public void testWeaklyConsistentIteration () {
465			final ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
466	dl	1.3	q.add(one);
467			q.add(two);
468			q.add(three);
469	dl	1.1
470			try {
471			for (Iterator it = q.iterator(); it.hasNext();) {
472			q.remove();
473			it.next();
474			}
475			}
476			catch (ConcurrentModificationException e) {
477	dl	1.4	shouldThrow();
478	dl	1.1	}
479
480			assertEquals("queue should be empty again", 0, q.size());
481			}
482
483	dl	1.4	/**
484	dl	1.5	* iterator.remove removes current element
485	dl	1.4	*/
486	dl	1.1	public void testIteratorRemove () {
487			final ConcurrentLinkedQueue q = new ConcurrentLinkedQueue();
488	dl	1.3	q.add(one);
489			q.add(two);
490			q.add(three);
491	dl	1.1	Iterator it = q.iterator();
492			it.next();
493			it.remove();
494			it = q.iterator();
495	dl	1.3	assertEquals(it.next(), two);
496			assertEquals(it.next(), three);
497	dl	1.1	assertFalse(it.hasNext());
498			}
499
500
501	dl	1.4	/**
502	dl	1.5	* toString contains toStrings of elements
503	dl	1.4	*/
504			public void testToString() {
505	dl	1.3	ConcurrentLinkedQueue q = populatedQueue(SIZE);
506	dl	1.1	String s = q.toString();
507	dl	1.3	for (int i = 0; i < SIZE; ++i) {
508	dl	1.1	assertTrue(s.indexOf(String.valueOf(i)) >= 0);
509			}
510			}
511	dl	1.2
512	dl	1.4	/**
513	dl	1.5	* A deserialized serialized queue has same elements in same order
514	dl	1.4	*/
515	dl	1.2	public void testSerialization() {
516	dl	1.3	ConcurrentLinkedQueue q = populatedQueue(SIZE);
517	dl	1.2	try {
518			ByteArrayOutputStream bout = new ByteArrayOutputStream(10000);
519			ObjectOutputStream out = new ObjectOutputStream(new BufferedOutputStream(bout));
520			out.writeObject(q);
521			out.close();
522
523			ByteArrayInputStream bin = new ByteArrayInputStream(bout.toByteArray());
524			ObjectInputStream in = new ObjectInputStream(new BufferedInputStream(bin));
525			ConcurrentLinkedQueue r = (ConcurrentLinkedQueue)in.readObject();
526			assertEquals(q.size(), r.size());
527			while (!q.isEmpty())
528			assertEquals(q.remove(), r.remove());
529			} catch(Exception e){
530	dl	1.4	unexpectedException();
531	dl	1.2	}
532			}
533	dl	1.1
534			}