test/tck/PriorityQueueTest.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 PriorityQueueTest extends JSR166TestCase {
    public static void main(String[] args) {
        junit.textui.TestRunner.run(suite());
    }
    public static Test suite() {
        return new TestSuite(PriorityQueueTest.class);
    }

    static class MyReverseComparator implements Comparator {
        public int compare(Object x, Object y) {
            return ((Comparable)y).compareTo(x);
        }
    }

    /**
     * Create a queue of given size containing consecutive
     * Integers 0 ... n.
     */
    private PriorityQueue<Integer> populatedQueue(int n) {
        PriorityQueue<Integer> q = new PriorityQueue<Integer>(n);
        assertTrue(q.isEmpty());
        for (int i = n-1; i >= 0; i-=2)
            assertTrue(q.offer(new Integer(i)));
        for (int i = (n & 1); i < n; i+=2)
            assertTrue(q.offer(new Integer(i)));
        assertFalse(q.isEmpty());
        assertEquals(n, q.size());
        return q;
    }

    /**
     * A new queue has unbounded capacity
     */
    public void testConstructor1() {
        assertEquals(0, new PriorityQueue(SIZE).size());
    }

    /**
     * Constructor throws IAE if capacity argument nonpositive
     */
    public void testConstructor2() {
        try {
            PriorityQueue q = new PriorityQueue(0);
            shouldThrow();
        } catch (IllegalArgumentException success) {}
    }

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

    /**
     * Initializing from Collection of null elements throws NPE
     */
    public void testConstructor4() {
        try {
            Integer[] ints = new Integer[SIZE];
            PriorityQueue q = new PriorityQueue(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);
            PriorityQueue q = new PriorityQueue(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);
        PriorityQueue q = new PriorityQueue(Arrays.asList(ints));
        for (int i = 0; i < SIZE; ++i)
            assertEquals(ints[i], q.poll());
    }

    /**
     * The comparator used in constructor is used
     */
    public void testConstructor7() {
        MyReverseComparator cmp = new MyReverseComparator();
        PriorityQueue q = new PriorityQueue(SIZE, cmp);
        assertEquals(cmp, q.comparator());
        Integer[] ints = new Integer[SIZE];
        for (int i = 0; i < SIZE; ++i)
            ints[i] = new Integer(i);
        q.addAll(Arrays.asList(ints));
        for (int i = SIZE-1; i >= 0; --i)
            assertEquals(ints[i], q.poll());
    }

    /**
     * isEmpty is true before add, false after
     */
    public void testEmpty() {
        PriorityQueue q = new PriorityQueue(2);
        assertTrue(q.isEmpty());
        q.add(new Integer(1));
        assertFalse(q.isEmpty());
        q.add(new Integer(2));
        q.remove();
        q.remove();
        assertTrue(q.isEmpty());
    }

    /**
     * size changes when elements added and removed
     */
    public void testSize() {
        PriorityQueue 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 {
            PriorityQueue q = new PriorityQueue(1);
            q.offer(null);
            shouldThrow();
        } catch (NullPointerException success) {}
    }

    /**
     * add(null) throws NPE
     */
    public void testAddNull() {
        try {
            PriorityQueue q = new PriorityQueue(1);
            q.add(null);
            shouldThrow();
        } catch (NullPointerException success) {}
    }

    /**
     * Offer of comparable element succeeds
     */
    public void testOffer() {
        PriorityQueue q = new PriorityQueue(1);
        assertTrue(q.offer(zero));
        assertTrue(q.offer(one));
    }

    /**
     * Offer of non-Comparable throws CCE
     */
    public void testOfferNonComparable() {
        try {
            PriorityQueue q = new PriorityQueue(1);
            q.offer(new Object());
            q.offer(new Object());
            q.offer(new Object());
            shouldThrow();
        } catch (ClassCastException success) {}
    }

    /**
     * add of comparable succeeds
     */
    public void testAdd() {
        PriorityQueue q = new PriorityQueue(SIZE);
        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 {
            PriorityQueue q = new PriorityQueue(1);
            q.addAll(null);
            shouldThrow();
        } catch (NullPointerException success) {}
    }

    /**
     * addAll of a collection with null elements throws NPE
     */
    public void testAddAll2() {
        try {
            PriorityQueue q = new PriorityQueue(SIZE);
            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 {
            PriorityQueue q = new PriorityQueue(SIZE);
            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 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(SIZE-1-i);
        PriorityQueue q = new PriorityQueue(SIZE);
        assertFalse(q.addAll(Arrays.asList(empty)));
        assertTrue(q.addAll(Arrays.asList(ints)));
        for (int i = 0; i < SIZE; ++i)
            assertEquals(new Integer(i), q.poll());
    }

    /**
     * poll succeeds unless empty
     */
    public void testPoll() {
        PriorityQueue 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() {
        PriorityQueue 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() {
        PriorityQueue 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() {
        PriorityQueue 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() {
        PriorityQueue 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() {
        PriorityQueue 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() {
        PriorityQueue q = populatedQueue(SIZE);
        q.clear();
        assertTrue(q.isEmpty());
        assertEquals(0, q.size());
        q.add(new Integer(1));
        assertFalse(q.isEmpty());
        q.clear();
        assertTrue(q.isEmpty());
    }

    /**
     * containsAll(c) is true when c contains a subset of elements
     */
    public void testContainsAll() {
        PriorityQueue q = populatedQueue(SIZE);
        PriorityQueue p = new PriorityQueue(SIZE);
        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 changed
     */
    public void testRetainAll() {
        PriorityQueue q = populatedQueue(SIZE);
        PriorityQueue 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) {
            PriorityQueue q = populatedQueue(SIZE);
            PriorityQueue 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() {
        PriorityQueue q = populatedQueue(SIZE);
        Object[] o = q.toArray();
        Arrays.sort(o);
        for (int i = 0; i < o.length; i++)
            assertSame(o[i], q.poll());
    }

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

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

    /**
     * iterator.remove removes current element
     */
    public void testIteratorRemove() {
        final PriorityQueue q = new PriorityQueue(3);
        q.add(new Integer(2));
        q.add(new Integer(1));
        q.add(new Integer(3));

        Iterator it = q.iterator();
        it.next();
        it.remove();

        it = q.iterator();
        assertEquals(it.next(), new Integer(2));
        assertEquals(it.next(), new Integer(3));
        assertFalse(it.hasNext());
    }

    /**
     * toString contains toStrings of elements
     */
    public void testToString() {
        PriorityQueue 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
     */
    public void testSerialization() throws Exception {
        PriorityQueue 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));
        PriorityQueue r = (PriorityQueue)in.readObject();
        assertEquals(q.size(), r.size());
        while (!q.isEmpty())
            assertEquals(q.remove(), r.remove());
    }
}
Revision:	1.22
Committed:	Fri May 27 19:52:35 2011 UTC (12 years, 11 months ago) by jsr166
Branch:	MAIN
Changes since 1.21:	+1 -2 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 PriorityQueueTest extends JSR166TestCase {
15	public static void main(String[] args) {
16	junit.textui.TestRunner.run(suite());
17	}
18	public static Test suite() {
19	return new TestSuite(PriorityQueueTest.class);
20	}
21
22	static class MyReverseComparator implements Comparator {
23	public int compare(Object x, Object y) {
24	return ((Comparable)y).compareTo(x);
25	}
26	}
27
28	/**
29	* Create a queue of given size containing consecutive
30	* Integers 0 ... n.
31	*/
32	private PriorityQueue<Integer> populatedQueue(int n) {
33	PriorityQueue<Integer> q = new PriorityQueue<Integer>(n);
34	assertTrue(q.isEmpty());
35	for (int i = n-1; i >= 0; i-=2)
36	assertTrue(q.offer(new Integer(i)));
37	for (int i = (n & 1); i < n; i+=2)
38	assertTrue(q.offer(new Integer(i)));
39	assertFalse(q.isEmpty());
40	assertEquals(n, q.size());
41	return q;
42	}
43
44	/**
45	* A new queue has unbounded capacity
46	*/
47	public void testConstructor1() {
48	assertEquals(0, new PriorityQueue(SIZE).size());
49	}
50
51	/**
52	* Constructor throws IAE if capacity argument nonpositive
53	*/
54	public void testConstructor2() {
55	try {
56	PriorityQueue q = new PriorityQueue(0);
57	shouldThrow();
58	} catch (IllegalArgumentException success) {}
59	}
60
61	/**
62	* Initializing from null Collection throws NPE
63	*/
64	public void testConstructor3() {
65	try {
66	PriorityQueue q = new PriorityQueue((Collection)null);
67	shouldThrow();
68	} catch (NullPointerException success) {}
69	}
70
71	/**
72	* Initializing from Collection of null elements throws NPE
73	*/
74	public void testConstructor4() {
75	try {
76	Integer[] ints = new Integer[SIZE];
77	PriorityQueue q = new PriorityQueue(Arrays.asList(ints));
78	shouldThrow();
79	} catch (NullPointerException success) {}
80	}
81
82	/**
83	* Initializing from Collection with some null elements throws NPE
84	*/
85	public void testConstructor5() {
86	try {
87	Integer[] ints = new Integer[SIZE];
88	for (int i = 0; i < SIZE-1; ++i)
89	ints[i] = new Integer(i);
90	PriorityQueue q = new PriorityQueue(Arrays.asList(ints));
91	shouldThrow();
92	} catch (NullPointerException success) {}
93	}
94
95	/**
96	* Queue contains all elements of collection used to initialize
97	*/
98	public void testConstructor6() {
99	Integer[] ints = new Integer[SIZE];
100	for (int i = 0; i < SIZE; ++i)
101	ints[i] = new Integer(i);
102	PriorityQueue q = new PriorityQueue(Arrays.asList(ints));
103	for (int i = 0; i < SIZE; ++i)
104	assertEquals(ints[i], q.poll());
105	}
106
107	/**
108	* The comparator used in constructor is used
109	*/
110	public void testConstructor7() {
111	MyReverseComparator cmp = new MyReverseComparator();
112	PriorityQueue q = new PriorityQueue(SIZE, cmp);
113	assertEquals(cmp, q.comparator());
114	Integer[] ints = new Integer[SIZE];
115	for (int i = 0; i < SIZE; ++i)
116	ints[i] = new Integer(i);
117	q.addAll(Arrays.asList(ints));
118	for (int i = SIZE-1; i >= 0; --i)
119	assertEquals(ints[i], q.poll());
120	}
121
122	/**
123	* isEmpty is true before add, false after
124	*/
125	public void testEmpty() {
126	PriorityQueue q = new PriorityQueue(2);
127	assertTrue(q.isEmpty());
128	q.add(new Integer(1));
129	assertFalse(q.isEmpty());
130	q.add(new Integer(2));
131	q.remove();
132	q.remove();
133	assertTrue(q.isEmpty());
134	}
135
136	/**
137	* size changes when elements added and removed
138	*/
139	public void testSize() {
140	PriorityQueue q = populatedQueue(SIZE);
141	for (int i = 0; i < SIZE; ++i) {
142	assertEquals(SIZE-i, q.size());
143	q.remove();
144	}
145	for (int i = 0; i < SIZE; ++i) {
146	assertEquals(i, q.size());
147	q.add(new Integer(i));
148	}
149	}
150
151	/**
152	* offer(null) throws NPE
153	*/
154	public void testOfferNull() {
155	try {
156	PriorityQueue q = new PriorityQueue(1);
157	q.offer(null);
158	shouldThrow();
159	} catch (NullPointerException success) {}
160	}
161
162	/**
163	* add(null) throws NPE
164	*/
165	public void testAddNull() {
166	try {
167	PriorityQueue q = new PriorityQueue(1);
168	q.add(null);
169	shouldThrow();
170	} catch (NullPointerException success) {}
171	}
172
173	/**
174	* Offer of comparable element succeeds
175	*/
176	public void testOffer() {
177	PriorityQueue q = new PriorityQueue(1);
178	assertTrue(q.offer(zero));
179	assertTrue(q.offer(one));
180	}
181
182	/**
183	* Offer of non-Comparable throws CCE
184	*/
185	public void testOfferNonComparable() {
186	try {
187	PriorityQueue q = new PriorityQueue(1);
188	q.offer(new Object());
189	q.offer(new Object());
190	q.offer(new Object());
191	shouldThrow();
192	} catch (ClassCastException success) {}
193	}
194
195	/**
196	* add of comparable succeeds
197	*/
198	public void testAdd() {
199	PriorityQueue q = new PriorityQueue(SIZE);
200	for (int i = 0; i < SIZE; ++i) {
201	assertEquals(i, q.size());
202	assertTrue(q.add(new Integer(i)));
203	}
204	}
205
206	/**
207	* addAll(null) throws NPE
208	*/
209	public void testAddAll1() {
210	try {
211	PriorityQueue q = new PriorityQueue(1);
212	q.addAll(null);
213	shouldThrow();
214	} catch (NullPointerException success) {}
215	}
216
217	/**
218	* addAll of a collection with null elements throws NPE
219	*/
220	public void testAddAll2() {
221	try {
222	PriorityQueue q = new PriorityQueue(SIZE);
223	Integer[] ints = new Integer[SIZE];
224	q.addAll(Arrays.asList(ints));
225	shouldThrow();
226	} catch (NullPointerException success) {}
227	}
228
229	/**
230	* addAll of a collection with any null elements throws NPE after
231	* possibly adding some elements
232	*/
233	public void testAddAll3() {
234	try {
235	PriorityQueue q = new PriorityQueue(SIZE);
236	Integer[] ints = new Integer[SIZE];
237	for (int i = 0; i < SIZE-1; ++i)
238	ints[i] = new Integer(i);
239	q.addAll(Arrays.asList(ints));
240	shouldThrow();
241	} catch (NullPointerException success) {}
242	}
243
244	/**
245	* Queue contains all elements of successful addAll
246	*/
247	public void testAddAll5() {
248	Integer[] empty = new Integer[0];
249	Integer[] ints = new Integer[SIZE];
250	for (int i = 0; i < SIZE; ++i)
251	ints[i] = new Integer(SIZE-1-i);
252	PriorityQueue q = new PriorityQueue(SIZE);
253	assertFalse(q.addAll(Arrays.asList(empty)));
254	assertTrue(q.addAll(Arrays.asList(ints)));
255	for (int i = 0; i < SIZE; ++i)
256	assertEquals(new Integer(i), q.poll());
257	}
258
259	/**
260	* poll succeeds unless empty
261	*/
262	public void testPoll() {
263	PriorityQueue q = populatedQueue(SIZE);
264	for (int i = 0; i < SIZE; ++i) {
265	assertEquals(i, q.poll());
266	}
267	assertNull(q.poll());
268	}
269
270	/**
271	* peek returns next element, or null if empty
272	*/
273	public void testPeek() {
274	PriorityQueue q = populatedQueue(SIZE);
275	for (int i = 0; i < SIZE; ++i) {
276	assertEquals(i, q.peek());
277	assertEquals(i, q.poll());
278	assertTrue(q.peek() == null \|\|
279	!q.peek().equals(i));
280	}
281	assertNull(q.peek());
282	}
283
284	/**
285	* element returns next element, or throws NSEE if empty
286	*/
287	public void testElement() {
288	PriorityQueue q = populatedQueue(SIZE);
289	for (int i = 0; i < SIZE; ++i) {
290	assertEquals(i, q.element());
291	assertEquals(i, q.poll());
292	}
293	try {
294	q.element();
295	shouldThrow();
296	} catch (NoSuchElementException success) {}
297	}
298
299	/**
300	* remove removes next element, or throws NSEE if empty
301	*/
302	public void testRemove() {
303	PriorityQueue q = populatedQueue(SIZE);
304	for (int i = 0; i < SIZE; ++i) {
305	assertEquals(i, q.remove());
306	}
307	try {
308	q.remove();
309	shouldThrow();
310	} catch (NoSuchElementException success) {}
311	}
312
313	/**
314	* remove(x) removes x and returns true if present
315	*/
316	public void testRemoveElement() {
317	PriorityQueue q = populatedQueue(SIZE);
318	for (int i = 1; i < SIZE; i+=2) {
319	assertTrue(q.contains(i));
320	assertTrue(q.remove(i));
321	assertFalse(q.contains(i));
322	assertTrue(q.contains(i-1));
323	}
324	for (int i = 0; i < SIZE; i+=2) {
325	assertTrue(q.contains(i));
326	assertTrue(q.remove(i));
327	assertFalse(q.contains(i));
328	assertFalse(q.remove(i+1));
329	assertFalse(q.contains(i+1));
330	}
331	assertTrue(q.isEmpty());
332	}
333
334	/**
335	* contains(x) reports true when elements added but not yet removed
336	*/
337	public void testContains() {
338	PriorityQueue q = populatedQueue(SIZE);
339	for (int i = 0; i < SIZE; ++i) {
340	assertTrue(q.contains(new Integer(i)));
341	q.poll();
342	assertFalse(q.contains(new Integer(i)));
343	}
344	}
345
346	/**
347	* clear removes all elements
348	*/
349	public void testClear() {
350	PriorityQueue q = populatedQueue(SIZE);
351	q.clear();
352	assertTrue(q.isEmpty());
353	assertEquals(0, q.size());
354	q.add(new Integer(1));
355	assertFalse(q.isEmpty());
356	q.clear();
357	assertTrue(q.isEmpty());
358	}
359
360	/**
361	* containsAll(c) is true when c contains a subset of elements
362	*/
363	public void testContainsAll() {
364	PriorityQueue q = populatedQueue(SIZE);
365	PriorityQueue p = new PriorityQueue(SIZE);
366	for (int i = 0; i < SIZE; ++i) {
367	assertTrue(q.containsAll(p));
368	assertFalse(p.containsAll(q));
369	p.add(new Integer(i));
370	}
371	assertTrue(p.containsAll(q));
372	}
373
374	/**
375	* retainAll(c) retains only those elements of c and reports true if changed
376	*/
377	public void testRetainAll() {
378	PriorityQueue q = populatedQueue(SIZE);
379	PriorityQueue p = populatedQueue(SIZE);
380	for (int i = 0; i < SIZE; ++i) {
381	boolean changed = q.retainAll(p);
382	if (i == 0)
383	assertFalse(changed);
384	else
385	assertTrue(changed);
386
387	assertTrue(q.containsAll(p));
388	assertEquals(SIZE-i, q.size());
389	p.remove();
390	}
391	}
392
393	/**
394	* removeAll(c) removes only those elements of c and reports true if changed
395	*/
396	public void testRemoveAll() {
397	for (int i = 1; i < SIZE; ++i) {
398	PriorityQueue q = populatedQueue(SIZE);
399	PriorityQueue p = populatedQueue(i);
400	assertTrue(q.removeAll(p));
401	assertEquals(SIZE-i, q.size());
402	for (int j = 0; j < i; ++j) {
403	Integer I = (Integer)(p.remove());
404	assertFalse(q.contains(I));
405	}
406	}
407	}
408
409	/**
410	* toArray contains all elements
411	*/
412	public void testToArray() {
413	PriorityQueue q = populatedQueue(SIZE);
414	Object[] o = q.toArray();
415	Arrays.sort(o);
416	for (int i = 0; i < o.length; i++)
417	assertSame(o[i], q.poll());
418	}
419
420	/**
421	* toArray(a) contains all elements
422	*/
423	public void testToArray2() {
424	PriorityQueue<Integer> q = populatedQueue(SIZE);
425	Integer[] ints = new Integer[SIZE];
426	Integer[] array = q.toArray(ints);
427	assertSame(ints, array);
428	Arrays.sort(ints);
429	for (int i = 0; i < ints.length; i++)
430	assertSame(ints[i], q.poll());
431	}
432
433	/**
434	* iterator iterates through all elements
435	*/
436	public void testIterator() {
437	PriorityQueue q = populatedQueue(SIZE);
438	int i = 0;
439	Iterator it = q.iterator();
440	while (it.hasNext()) {
441	assertTrue(q.contains(it.next()));
442	++i;
443	}
444	assertEquals(i, SIZE);
445	}
446
447	/**
448	* iterator.remove removes current element
449	*/
450	public void testIteratorRemove() {
451	final PriorityQueue q = new PriorityQueue(3);
452	q.add(new Integer(2));
453	q.add(new Integer(1));
454	q.add(new Integer(3));
455
456	Iterator it = q.iterator();
457	it.next();
458	it.remove();
459
460	it = q.iterator();
461	assertEquals(it.next(), new Integer(2));
462	assertEquals(it.next(), new Integer(3));
463	assertFalse(it.hasNext());
464	}
465
466	/**
467	* toString contains toStrings of elements
468	*/
469	public void testToString() {
470	PriorityQueue q = populatedQueue(SIZE);
471	String s = q.toString();
472	for (int i = 0; i < SIZE; ++i) {
473	assertTrue(s.contains(String.valueOf(i)));
474	}
475	}
476
477	/**
478	* A deserialized serialized queue has same elements
479	*/
480	public void testSerialization() throws Exception {
481	PriorityQueue q = populatedQueue(SIZE);
482	ByteArrayOutputStream bout = new ByteArrayOutputStream(10000);
483	ObjectOutputStream out = new ObjectOutputStream(new BufferedOutputStream(bout));
484	out.writeObject(q);
485	out.close();
486
487	ByteArrayInputStream bin = new ByteArrayInputStream(bout.toByteArray());
488	ObjectInputStream in = new ObjectInputStream(new BufferedInputStream(bin));
489	PriorityQueue r = (PriorityQueue)in.readObject();
490	assertEquals(q.size(), r.size());
491	while (!q.isEmpty())
492	assertEquals(q.remove(), r.remove());
493	}
494	}