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/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 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) {
            int i = ((Integer)x).intValue();
            int j = ((Integer)y).intValue();
            if (i < j) return 1;
            if (i > j) return -1;
            return 0;
        }
    }

    /**
     * Create a queue of given size containing consecutive
     * Integers 0 ... n.
     */
    private PriorityQueue populatedQueue(int n) {
        PriorityQueue q = new PriorityQueue(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() {
        try {
            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());
        }
        finally {}
    }

    /**
     * The comparator used in constructor is used
     */
    public void testConstructor7() {
        try {
            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());
        }
        finally {}
    }

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

    /**
     * poll succeeds unless empty
     */
    public void testPoll() {
        PriorityQueue 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() {
        PriorityQueue 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() {
        PriorityQueue 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() {
        PriorityQueue 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() {
        PriorityQueue 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() {
        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++)
            assertEquals(o[i], q.poll());
    }

    /**
     * toArray(a) contains all elements
     */
    public void testToArray2() {
        PriorityQueue 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());
    }

    /**
     * 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.indexOf(String.valueOf(i)) >= 0);
        }
    }

    /**
     * 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:	1.13
Committed:	Sat Nov 21 10:25:05 2009 UTC (14 years, 5 months ago) by jsr166
Branch:	MAIN
Changes since 1.12:	+25 -39 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 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	int i = ((Integer)x).intValue();
25	int j = ((Integer)y).intValue();
26	if (i < j) return 1;
27	if (i > j) return -1;
28	return 0;
29	}
30	}
31
32	/**
33	* Create a queue of given size containing consecutive
34	* Integers 0 ... n.
35	*/
36	private PriorityQueue populatedQueue(int n) {
37	PriorityQueue q = new PriorityQueue(n);
38	assertTrue(q.isEmpty());
39	for (int i = n-1; i >= 0; i-=2)
40	assertTrue(q.offer(new Integer(i)));
41	for (int i = (n & 1); i < n; i+=2)
42	assertTrue(q.offer(new Integer(i)));
43	assertFalse(q.isEmpty());
44	assertEquals(n, q.size());
45	return q;
46	}
47
48	/**
49	* A new queue has unbounded capacity
50	*/
51	public void testConstructor1() {
52	assertEquals(0, new PriorityQueue(SIZE).size());
53	}
54
55	/**
56	* Constructor throws IAE if capacity argument nonpositive
57	*/
58	public void testConstructor2() {
59	try {
60	PriorityQueue q = new PriorityQueue(0);
61	shouldThrow();
62	} catch (IllegalArgumentException success) {}
63	}
64
65	/**
66	* Initializing from null Collection throws NPE
67	*/
68	public void testConstructor3() {
69	try {
70	PriorityQueue q = new PriorityQueue((Collection)null);
71	shouldThrow();
72	} catch (NullPointerException success) {}
73	}
74
75	/**
76	* Initializing from Collection of null elements throws NPE
77	*/
78	public void testConstructor4() {
79	try {
80	Integer[] ints = new Integer[SIZE];
81	PriorityQueue q = new PriorityQueue(Arrays.asList(ints));
82	shouldThrow();
83	} catch (NullPointerException success) {}
84	}
85
86	/**
87	* Initializing from Collection with some null elements throws NPE
88	*/
89	public void testConstructor5() {
90	try {
91	Integer[] ints = new Integer[SIZE];
92	for (int i = 0; i < SIZE-1; ++i)
93	ints[i] = new Integer(i);
94	PriorityQueue q = new PriorityQueue(Arrays.asList(ints));
95	shouldThrow();
96	} catch (NullPointerException success) {}
97	}
98
99	/**
100	* Queue contains all elements of collection used to initialize
101	*/
102	public void testConstructor6() {
103	try {
104	Integer[] ints = new Integer[SIZE];
105	for (int i = 0; i < SIZE; ++i)
106	ints[i] = new Integer(i);
107	PriorityQueue q = new PriorityQueue(Arrays.asList(ints));
108	for (int i = 0; i < SIZE; ++i)
109	assertEquals(ints[i], q.poll());
110	}
111	finally {}
112	}
113
114	/**
115	* The comparator used in constructor is used
116	*/
117	public void testConstructor7() {
118	try {
119	MyReverseComparator cmp = new MyReverseComparator();
120	PriorityQueue q = new PriorityQueue(SIZE, cmp);
121	assertEquals(cmp, q.comparator());
122	Integer[] ints = new Integer[SIZE];
123	for (int i = 0; i < SIZE; ++i)
124	ints[i] = new Integer(i);
125	q.addAll(Arrays.asList(ints));
126	for (int i = SIZE-1; i >= 0; --i)
127	assertEquals(ints[i], q.poll());
128	}
129	finally {}
130	}
131
132	/**
133	* isEmpty is true before add, false after
134	*/
135	public void testEmpty() {
136	PriorityQueue q = new PriorityQueue(2);
137	assertTrue(q.isEmpty());
138	q.add(new Integer(1));
139	assertFalse(q.isEmpty());
140	q.add(new Integer(2));
141	q.remove();
142	q.remove();
143	assertTrue(q.isEmpty());
144	}
145
146	/**
147	* size changes when elements added and removed
148	*/
149	public void testSize() {
150	PriorityQueue q = populatedQueue(SIZE);
151	for (int i = 0; i < SIZE; ++i) {
152	assertEquals(SIZE-i, q.size());
153	q.remove();
154	}
155	for (int i = 0; i < SIZE; ++i) {
156	assertEquals(i, q.size());
157	q.add(new Integer(i));
158	}
159	}
160
161	/**
162	* offer(null) throws NPE
163	*/
164	public void testOfferNull() {
165	try {
166	PriorityQueue q = new PriorityQueue(1);
167	q.offer(null);
168	shouldThrow();
169	} catch (NullPointerException success) {}
170	}
171
172	/**
173	* add(null) throws NPE
174	*/
175	public void testAddNull() {
176	try {
177	PriorityQueue q = new PriorityQueue(1);
178	q.add(null);
179	shouldThrow();
180	} catch (NullPointerException success) {}
181	}
182
183	/**
184	* Offer of comparable element succeeds
185	*/
186	public void testOffer() {
187	PriorityQueue q = new PriorityQueue(1);
188	assertTrue(q.offer(zero));
189	assertTrue(q.offer(one));
190	}
191
192	/**
193	* Offer of non-Comparable throws CCE
194	*/
195	public void testOfferNonComparable() {
196	try {
197	PriorityQueue q = new PriorityQueue(1);
198	q.offer(new Object());
199	q.offer(new Object());
200	q.offer(new Object());
201	shouldThrow();
202	} catch (ClassCastException success) {}
203	}
204
205	/**
206	* add of comparable succeeds
207	*/
208	public void testAdd() {
209	PriorityQueue q = new PriorityQueue(SIZE);
210	for (int i = 0; i < SIZE; ++i) {
211	assertEquals(i, q.size());
212	assertTrue(q.add(new Integer(i)));
213	}
214	}
215
216	/**
217	* addAll(null) throws NPE
218	*/
219	public void testAddAll1() {
220	try {
221	PriorityQueue q = new PriorityQueue(1);
222	q.addAll(null);
223	shouldThrow();
224	} catch (NullPointerException success) {}
225	}
226	/**
227	* addAll of a collection with null elements throws NPE
228	*/
229	public void testAddAll2() {
230	try {
231	PriorityQueue q = new PriorityQueue(SIZE);
232	Integer[] ints = new Integer[SIZE];
233	q.addAll(Arrays.asList(ints));
234	shouldThrow();
235	} catch (NullPointerException success) {}
236	}
237	/**
238	* addAll of a collection with any null elements throws NPE after
239	* possibly adding some elements
240	*/
241	public void testAddAll3() {
242	try {
243	PriorityQueue q = new PriorityQueue(SIZE);
244	Integer[] ints = new Integer[SIZE];
245	for (int i = 0; i < SIZE-1; ++i)
246	ints[i] = new Integer(i);
247	q.addAll(Arrays.asList(ints));
248	shouldThrow();
249	} catch (NullPointerException success) {}
250	}
251
252	/**
253	* Queue contains all elements of successful addAll
254	*/
255	public void testAddAll5() {
256	try {
257	Integer[] empty = new Integer[0];
258	Integer[] ints = new Integer[SIZE];
259	for (int i = 0; i < SIZE; ++i)
260	ints[i] = new Integer(SIZE-1-i);
261	PriorityQueue q = new PriorityQueue(SIZE);
262	assertFalse(q.addAll(Arrays.asList(empty)));
263	assertTrue(q.addAll(Arrays.asList(ints)));
264	for (int i = 0; i < SIZE; ++i)
265	assertEquals(new Integer(i), q.poll());
266	}
267	finally {}
268	}
269
270	/**
271	* poll succeeds unless empty
272	*/
273	public void testPoll() {
274	PriorityQueue q = populatedQueue(SIZE);
275	for (int i = 0; i < SIZE; ++i) {
276	assertEquals(i, ((Integer)q.poll()).intValue());
277	}
278	assertNull(q.poll());
279	}
280
281	/**
282	* peek returns next element, or null if empty
283	*/
284	public void testPeek() {
285	PriorityQueue q = populatedQueue(SIZE);
286	for (int i = 0; i < SIZE; ++i) {
287	assertEquals(i, ((Integer)q.peek()).intValue());
288	q.poll();
289	assertTrue(q.peek() == null \|\|
290	i != ((Integer)q.peek()).intValue());
291	}
292	assertNull(q.peek());
293	}
294
295	/**
296	* element returns next element, or throws NSEE if empty
297	*/
298	public void testElement() {
299	PriorityQueue q = populatedQueue(SIZE);
300	for (int i = 0; i < SIZE; ++i) {
301	assertEquals(i, ((Integer)q.element()).intValue());
302	q.poll();
303	}
304	try {
305	q.element();
306	shouldThrow();
307	} catch (NoSuchElementException success) {}
308	}
309
310	/**
311	* remove removes next element, or throws NSEE if empty
312	*/
313	public void testRemove() {
314	PriorityQueue q = populatedQueue(SIZE);
315	for (int i = 0; i < SIZE; ++i) {
316	assertEquals(i, ((Integer)q.remove()).intValue());
317	}
318	try {
319	q.remove();
320	shouldThrow();
321	} catch (NoSuchElementException success) {}
322	}
323
324	/**
325	* remove(x) removes x and returns true if present
326	*/
327	public void testRemoveElement() {
328	PriorityQueue q = populatedQueue(SIZE);
329	for (int i = 1; i < SIZE; i+=2) {
330	assertTrue(q.remove(new Integer(i)));
331	}
332	for (int i = 0; i < SIZE; i+=2) {
333	assertTrue(q.remove(new Integer(i)));
334	assertFalse(q.remove(new Integer(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 I = (Integer)(p.remove());
409	assertFalse(q.contains(I));
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	assertEquals(o[i], q.poll());
423	}
424
425	/**
426	* toArray(a) contains all elements
427	*/
428	public void testToArray2() {
429	PriorityQueue q = populatedQueue(SIZE);
430	Integer[] ints = new Integer[SIZE];
431	ints = (Integer[])q.toArray(ints);
432	Arrays.sort(ints);
433	for (int i = 0; i < ints.length; i++)
434	assertEquals(ints[i], q.poll());
435	}
436
437	/**
438	* iterator iterates through all elements
439	*/
440	public void testIterator() {
441	PriorityQueue q = populatedQueue(SIZE);
442	int i = 0;
443	Iterator it = q.iterator();
444	while (it.hasNext()) {
445	assertTrue(q.contains(it.next()));
446	++i;
447	}
448	assertEquals(i, SIZE);
449	}
450
451	/**
452	* iterator.remove removes current element
453	*/
454	public void testIteratorRemove () {
455	final PriorityQueue q = new PriorityQueue(3);
456	q.add(new Integer(2));
457	q.add(new Integer(1));
458	q.add(new Integer(3));
459
460	Iterator it = q.iterator();
461	it.next();
462	it.remove();
463
464	it = q.iterator();
465	assertEquals(it.next(), new Integer(2));
466	assertEquals(it.next(), new Integer(3));
467	assertFalse(it.hasNext());
468	}
469
470
471	/**
472	* toString contains toStrings of elements
473	*/
474	public void testToString() {
475	PriorityQueue q = populatedQueue(SIZE);
476	String s = q.toString();
477	for (int i = 0; i < SIZE; ++i) {
478	assertTrue(s.indexOf(String.valueOf(i)) >= 0);
479	}
480	}
481
482	/**
483	* A deserialized serialized queue has same elements
484	*/
485	public void testSerialization() throws Exception {
486	PriorityQueue q = populatedQueue(SIZE);
487	ByteArrayOutputStream bout = new ByteArrayOutputStream(10000);
488	ObjectOutputStream out = new ObjectOutputStream(new BufferedOutputStream(bout));
489	out.writeObject(q);
490	out.close();
491
492	ByteArrayInputStream bin = new ByteArrayInputStream(bout.toByteArray());
493	ObjectInputStream in = new ObjectInputStream(new BufferedInputStream(bin));
494	PriorityQueue r = (PriorityQueue)in.readObject();
495	assertEquals(q.size(), r.size());
496	while (!q.isEmpty())
497	assertEquals(q.remove(), r.remove());
498	}
499	}