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 java.util.Arrays;
import java.util.Collection;
import java.util.Comparator;
import java.util.Iterator;
import java.util.NoSuchElementException;
import java.util.PriorityQueue;
import java.util.Queue;

import junit.framework.Test;
import junit.framework.TestSuite;

public class PriorityQueueTest extends JSR166TestCase {
    public static void main(String[] args) {
        main(suite(), args);
    }
    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);
        }
    }

    /**
     * Returns a new 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 {
            new PriorityQueue(0);
            shouldThrow();
        } catch (IllegalArgumentException success) {}
    }

    /**
     * Initializing from null Collection throws NPE
     */
    public void testConstructor3() {
        try {
            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];
            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);
            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() {
        PriorityQueue q = new PriorityQueue(1);
        try {
            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 x = (Integer)(p.remove());
                assertFalse(q.contains(x));
            }
        }
    }

    /**
     * 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);
        Iterator it = q.iterator();
        int i;
        for (i = 0; it.hasNext(); i++)
            assertTrue(q.contains(it.next()));
        assertEquals(i, SIZE);
        assertIteratorExhausted(it);
    }

    /**
     * iterator of empty collection has no elements
     */
    public void testEmptyIterator() {
        assertIteratorExhausted(new PriorityQueue().iterator());
    }

    /**
     * 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 {
        Queue x = populatedQueue(SIZE);
        Queue y = serialClone(x);

        assertNotSame(x, y);
        assertEquals(x.size(), y.size());
        while (!x.isEmpty()) {
            assertFalse(y.isEmpty());
            assertEquals(x.remove(), y.remove());
        }
        assertTrue(y.isEmpty());
    }
}
Revision:	1.33
Committed:	Sat Apr 25 04:55:31 2015 UTC (9 years ago) by jsr166
Branch:	MAIN
Changes since 1.32:	+1 -1 lines
Log Message:	improve main methods; respect system properties; actually fail if a test fails
#	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 java.util.Arrays;
10	import java.util.Collection;
11	import java.util.Comparator;
12	import java.util.Iterator;
13	import java.util.NoSuchElementException;
14	import java.util.PriorityQueue;
15	import java.util.Queue;
16
17	import junit.framework.Test;
18	import junit.framework.TestSuite;
19
20	public class PriorityQueueTest extends JSR166TestCase {
21	public static void main(String[] args) {
22	main(suite(), args);
23	}
24	public static Test suite() {
25	return new TestSuite(PriorityQueueTest.class);
26	}
27
28	static class MyReverseComparator implements Comparator {
29	public int compare(Object x, Object y) {
30	return ((Comparable)y).compareTo(x);
31	}
32	}
33
34	/**
35	* Returns a new queue of given size containing consecutive
36	* Integers 0 ... n.
37	*/
38	private PriorityQueue<Integer> populatedQueue(int n) {
39	PriorityQueue<Integer> q = new PriorityQueue<Integer>(n);
40	assertTrue(q.isEmpty());
41	for (int i = n-1; i >= 0; i -= 2)
42	assertTrue(q.offer(new Integer(i)));
43	for (int i = (n & 1); i < n; i += 2)
44	assertTrue(q.offer(new Integer(i)));
45	assertFalse(q.isEmpty());
46	assertEquals(n, q.size());
47	return q;
48	}
49
50	/**
51	* A new queue has unbounded capacity
52	*/
53	public void testConstructor1() {
54	assertEquals(0, new PriorityQueue(SIZE).size());
55	}
56
57	/**
58	* Constructor throws IAE if capacity argument nonpositive
59	*/
60	public void testConstructor2() {
61	try {
62	new PriorityQueue(0);
63	shouldThrow();
64	} catch (IllegalArgumentException success) {}
65	}
66
67	/**
68	* Initializing from null Collection throws NPE
69	*/
70	public void testConstructor3() {
71	try {
72	new PriorityQueue((Collection)null);
73	shouldThrow();
74	} catch (NullPointerException success) {}
75	}
76
77	/**
78	* Initializing from Collection of null elements throws NPE
79	*/
80	public void testConstructor4() {
81	try {
82	Integer[] ints = new Integer[SIZE];
83	new PriorityQueue(Arrays.asList(ints));
84	shouldThrow();
85	} catch (NullPointerException success) {}
86	}
87
88	/**
89	* Initializing from Collection with some null elements throws NPE
90	*/
91	public void testConstructor5() {
92	try {
93	Integer[] ints = new Integer[SIZE];
94	for (int i = 0; i < SIZE-1; ++i)
95	ints[i] = new Integer(i);
96	new PriorityQueue(Arrays.asList(ints));
97	shouldThrow();
98	} catch (NullPointerException success) {}
99	}
100
101	/**
102	* Queue contains all elements of collection used to initialize
103	*/
104	public void testConstructor6() {
105	Integer[] ints = new Integer[SIZE];
106	for (int i = 0; i < SIZE; ++i)
107	ints[i] = new Integer(i);
108	PriorityQueue q = new PriorityQueue(Arrays.asList(ints));
109	for (int i = 0; i < SIZE; ++i)
110	assertEquals(ints[i], q.poll());
111	}
112
113	/**
114	* The comparator used in constructor is used
115	*/
116	public void testConstructor7() {
117	MyReverseComparator cmp = new MyReverseComparator();
118	PriorityQueue q = new PriorityQueue(SIZE, cmp);
119	assertEquals(cmp, q.comparator());
120	Integer[] ints = new Integer[SIZE];
121	for (int i = 0; i < SIZE; ++i)
122	ints[i] = new Integer(i);
123	q.addAll(Arrays.asList(ints));
124	for (int i = SIZE-1; i >= 0; --i)
125	assertEquals(ints[i], q.poll());
126	}
127
128	/**
129	* isEmpty is true before add, false after
130	*/
131	public void testEmpty() {
132	PriorityQueue q = new PriorityQueue(2);
133	assertTrue(q.isEmpty());
134	q.add(new Integer(1));
135	assertFalse(q.isEmpty());
136	q.add(new Integer(2));
137	q.remove();
138	q.remove();
139	assertTrue(q.isEmpty());
140	}
141
142	/**
143	* size changes when elements added and removed
144	*/
145	public void testSize() {
146	PriorityQueue q = populatedQueue(SIZE);
147	for (int i = 0; i < SIZE; ++i) {
148	assertEquals(SIZE-i, q.size());
149	q.remove();
150	}
151	for (int i = 0; i < SIZE; ++i) {
152	assertEquals(i, q.size());
153	q.add(new Integer(i));
154	}
155	}
156
157	/**
158	* offer(null) throws NPE
159	*/
160	public void testOfferNull() {
161	try {
162	PriorityQueue q = new PriorityQueue(1);
163	q.offer(null);
164	shouldThrow();
165	} catch (NullPointerException success) {}
166	}
167
168	/**
169	* add(null) throws NPE
170	*/
171	public void testAddNull() {
172	try {
173	PriorityQueue q = new PriorityQueue(1);
174	q.add(null);
175	shouldThrow();
176	} catch (NullPointerException success) {}
177	}
178
179	/**
180	* Offer of comparable element succeeds
181	*/
182	public void testOffer() {
183	PriorityQueue q = new PriorityQueue(1);
184	assertTrue(q.offer(zero));
185	assertTrue(q.offer(one));
186	}
187
188	/**
189	* Offer of non-Comparable throws CCE
190	*/
191	public void testOfferNonComparable() {
192	PriorityQueue q = new PriorityQueue(1);
193	try {
194	q.offer(new Object());
195	q.offer(new Object());
196	shouldThrow();
197	} catch (ClassCastException success) {}
198	}
199
200	/**
201	* add of comparable succeeds
202	*/
203	public void testAdd() {
204	PriorityQueue q = new PriorityQueue(SIZE);
205	for (int i = 0; i < SIZE; ++i) {
206	assertEquals(i, q.size());
207	assertTrue(q.add(new Integer(i)));
208	}
209	}
210
211	/**
212	* addAll(null) throws NPE
213	*/
214	public void testAddAll1() {
215	try {
216	PriorityQueue q = new PriorityQueue(1);
217	q.addAll(null);
218	shouldThrow();
219	} catch (NullPointerException success) {}
220	}
221
222	/**
223	* addAll of a collection with null elements throws NPE
224	*/
225	public void testAddAll2() {
226	try {
227	PriorityQueue q = new PriorityQueue(SIZE);
228	Integer[] ints = new Integer[SIZE];
229	q.addAll(Arrays.asList(ints));
230	shouldThrow();
231	} catch (NullPointerException success) {}
232	}
233
234	/**
235	* addAll of a collection with any null elements throws NPE after
236	* possibly adding some elements
237	*/
238	public void testAddAll3() {
239	try {
240	PriorityQueue q = new PriorityQueue(SIZE);
241	Integer[] ints = new Integer[SIZE];
242	for (int i = 0; i < SIZE-1; ++i)
243	ints[i] = new Integer(i);
244	q.addAll(Arrays.asList(ints));
245	shouldThrow();
246	} catch (NullPointerException success) {}
247	}
248
249	/**
250	* Queue contains all elements of successful addAll
251	*/
252	public void testAddAll5() {
253	Integer[] empty = new Integer[0];
254	Integer[] ints = new Integer[SIZE];
255	for (int i = 0; i < SIZE; ++i)
256	ints[i] = new Integer(SIZE-1-i);
257	PriorityQueue q = new PriorityQueue(SIZE);
258	assertFalse(q.addAll(Arrays.asList(empty)));
259	assertTrue(q.addAll(Arrays.asList(ints)));
260	for (int i = 0; i < SIZE; ++i)
261	assertEquals(new Integer(i), q.poll());
262	}
263
264	/**
265	* poll succeeds unless empty
266	*/
267	public void testPoll() {
268	PriorityQueue q = populatedQueue(SIZE);
269	for (int i = 0; i < SIZE; ++i) {
270	assertEquals(i, q.poll());
271	}
272	assertNull(q.poll());
273	}
274
275	/**
276	* peek returns next element, or null if empty
277	*/
278	public void testPeek() {
279	PriorityQueue q = populatedQueue(SIZE);
280	for (int i = 0; i < SIZE; ++i) {
281	assertEquals(i, q.peek());
282	assertEquals(i, q.poll());
283	assertTrue(q.peek() == null \|\|
284	!q.peek().equals(i));
285	}
286	assertNull(q.peek());
287	}
288
289	/**
290	* element returns next element, or throws NSEE if empty
291	*/
292	public void testElement() {
293	PriorityQueue q = populatedQueue(SIZE);
294	for (int i = 0; i < SIZE; ++i) {
295	assertEquals(i, q.element());
296	assertEquals(i, q.poll());
297	}
298	try {
299	q.element();
300	shouldThrow();
301	} catch (NoSuchElementException success) {}
302	}
303
304	/**
305	* remove removes next element, or throws NSEE if empty
306	*/
307	public void testRemove() {
308	PriorityQueue q = populatedQueue(SIZE);
309	for (int i = 0; i < SIZE; ++i) {
310	assertEquals(i, q.remove());
311	}
312	try {
313	q.remove();
314	shouldThrow();
315	} catch (NoSuchElementException success) {}
316	}
317
318	/**
319	* remove(x) removes x and returns true if present
320	*/
321	public void testRemoveElement() {
322	PriorityQueue q = populatedQueue(SIZE);
323	for (int i = 1; i < SIZE; i += 2) {
324	assertTrue(q.contains(i));
325	assertTrue(q.remove(i));
326	assertFalse(q.contains(i));
327	assertTrue(q.contains(i-1));
328	}
329	for (int i = 0; i < SIZE; i += 2) {
330	assertTrue(q.contains(i));
331	assertTrue(q.remove(i));
332	assertFalse(q.contains(i));
333	assertFalse(q.remove(i+1));
334	assertFalse(q.contains(i+1));
335	}
336	assertTrue(q.isEmpty());
337	}
338
339	/**
340	* contains(x) reports true when elements added but not yet removed
341	*/
342	public void testContains() {
343	PriorityQueue q = populatedQueue(SIZE);
344	for (int i = 0; i < SIZE; ++i) {
345	assertTrue(q.contains(new Integer(i)));
346	q.poll();
347	assertFalse(q.contains(new Integer(i)));
348	}
349	}
350
351	/**
352	* clear removes all elements
353	*/
354	public void testClear() {
355	PriorityQueue q = populatedQueue(SIZE);
356	q.clear();
357	assertTrue(q.isEmpty());
358	assertEquals(0, q.size());
359	q.add(new Integer(1));
360	assertFalse(q.isEmpty());
361	q.clear();
362	assertTrue(q.isEmpty());
363	}
364
365	/**
366	* containsAll(c) is true when c contains a subset of elements
367	*/
368	public void testContainsAll() {
369	PriorityQueue q = populatedQueue(SIZE);
370	PriorityQueue p = new PriorityQueue(SIZE);
371	for (int i = 0; i < SIZE; ++i) {
372	assertTrue(q.containsAll(p));
373	assertFalse(p.containsAll(q));
374	p.add(new Integer(i));
375	}
376	assertTrue(p.containsAll(q));
377	}
378
379	/**
380	* retainAll(c) retains only those elements of c and reports true if changed
381	*/
382	public void testRetainAll() {
383	PriorityQueue q = populatedQueue(SIZE);
384	PriorityQueue p = populatedQueue(SIZE);
385	for (int i = 0; i < SIZE; ++i) {
386	boolean changed = q.retainAll(p);
387	if (i == 0)
388	assertFalse(changed);
389	else
390	assertTrue(changed);
391
392	assertTrue(q.containsAll(p));
393	assertEquals(SIZE-i, q.size());
394	p.remove();
395	}
396	}
397
398	/**
399	* removeAll(c) removes only those elements of c and reports true if changed
400	*/
401	public void testRemoveAll() {
402	for (int i = 1; i < SIZE; ++i) {
403	PriorityQueue q = populatedQueue(SIZE);
404	PriorityQueue p = populatedQueue(i);
405	assertTrue(q.removeAll(p));
406	assertEquals(SIZE-i, q.size());
407	for (int j = 0; j < i; ++j) {
408	Integer x = (Integer)(p.remove());
409	assertFalse(q.contains(x));
410	}
411	}
412	}
413
414	/**
415	* toArray contains all elements
416	*/
417	public void testToArray() {
418	PriorityQueue q = populatedQueue(SIZE);
419	Object[] o = q.toArray();
420	Arrays.sort(o);
421	for (int i = 0; i < o.length; i++)
422	assertSame(o[i], q.poll());
423	}
424
425	/**
426	* toArray(a) contains all elements
427	*/
428	public void testToArray2() {
429	PriorityQueue<Integer> q = populatedQueue(SIZE);
430	Integer[] ints = new Integer[SIZE];
431	Integer[] array = q.toArray(ints);
432	assertSame(ints, array);
433	Arrays.sort(ints);
434	for (int i = 0; i < ints.length; i++)
435	assertSame(ints[i], q.poll());
436	}
437
438	/**
439	* iterator iterates through all elements
440	*/
441	public void testIterator() {
442	PriorityQueue q = populatedQueue(SIZE);
443	Iterator it = q.iterator();
444	int i;
445	for (i = 0; it.hasNext(); i++)
446	assertTrue(q.contains(it.next()));
447	assertEquals(i, SIZE);
448	assertIteratorExhausted(it);
449	}
450
451	/**
452	* iterator of empty collection has no elements
453	*/
454	public void testEmptyIterator() {
455	assertIteratorExhausted(new PriorityQueue().iterator());
456	}
457
458	/**
459	* iterator.remove removes current element
460	*/
461	public void testIteratorRemove() {
462	final PriorityQueue q = new PriorityQueue(3);
463	q.add(new Integer(2));
464	q.add(new Integer(1));
465	q.add(new Integer(3));
466
467	Iterator it = q.iterator();
468	it.next();
469	it.remove();
470
471	it = q.iterator();
472	assertEquals(it.next(), new Integer(2));
473	assertEquals(it.next(), new Integer(3));
474	assertFalse(it.hasNext());
475	}
476
477	/**
478	* toString contains toStrings of elements
479	*/
480	public void testToString() {
481	PriorityQueue q = populatedQueue(SIZE);
482	String s = q.toString();
483	for (int i = 0; i < SIZE; ++i) {
484	assertTrue(s.contains(String.valueOf(i)));
485	}
486	}
487
488	/**
489	* A deserialized serialized queue has same elements
490	*/
491	public void testSerialization() throws Exception {
492	Queue x = populatedQueue(SIZE);
493	Queue y = serialClone(x);
494
495	assertNotSame(x, y);
496	assertEquals(x.size(), y.size());
497	while (!x.isEmpty()) {
498	assertFalse(y.isEmpty());
499	assertEquals(x.remove(), y.remove());
500	}
501	assertTrue(y.isEmpty());
502	}
503	}