test/tck/CopyOnWriteArraySetTest.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.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Iterator;
import java.util.NoSuchElementException;
import java.util.Set;
import java.util.concurrent.CopyOnWriteArraySet;

import junit.framework.Test;

public class CopyOnWriteArraySetTest extends JSR166TestCase {
    public static void main(String[] args) {
        main(suite(), args);
    }
    public static Test suite() {
        class Implementation implements CollectionImplementation {
            public Class<?> klazz() { return CopyOnWriteArraySet.class; }
            public Set emptyCollection() { return new CopyOnWriteArraySet(); }
            public Object makeElement(int i) { return i; }
            public boolean isConcurrent() { return true; }
            public boolean permitsNulls() { return true; }
        }
        return newTestSuite(
                CopyOnWriteArraySetTest.class,
                CollectionTest.testSuite(new Implementation()));
    }

    static CopyOnWriteArraySet<Integer> populatedSet(int n) {
        CopyOnWriteArraySet<Integer> a = new CopyOnWriteArraySet<>();
        assertTrue(a.isEmpty());
        for (int i = 0; i < n; i++)
            a.add(i);
        assertEquals(n == 0, a.isEmpty());
        assertEquals(n, a.size());
        return a;
    }

    static CopyOnWriteArraySet populatedSet(Integer[] elements) {
        CopyOnWriteArraySet<Integer> a = new CopyOnWriteArraySet<>();
        assertTrue(a.isEmpty());
        for (int i = 0; i < elements.length; i++)
            a.add(elements[i]);
        assertFalse(a.isEmpty());
        assertEquals(elements.length, a.size());
        return a;
    }

    /**
     * Default-constructed set is empty
     */
    public void testConstructor() {
        CopyOnWriteArraySet a = new CopyOnWriteArraySet();
        assertTrue(a.isEmpty());
    }

    /**
     * Collection-constructed set holds all of its elements
     */
    public void testConstructor3() {
        Integer[] ints = new Integer[SIZE];
        for (int i = 0; i < SIZE - 1; ++i)
            ints[i] = new Integer(i);
        CopyOnWriteArraySet a = new CopyOnWriteArraySet(Arrays.asList(ints));
        for (int i = 0; i < SIZE; ++i)
            assertTrue(a.contains(ints[i]));
    }

    /**
     * addAll adds each non-duplicate element from the given collection
     */
    public void testAddAll() {
        Set full = populatedSet(3);
        assertTrue(full.addAll(Arrays.asList(three, four, five)));
        assertEquals(6, full.size());
        assertFalse(full.addAll(Arrays.asList(three, four, five)));
        assertEquals(6, full.size());
    }

    /**
     * addAll adds each non-duplicate element from the given collection
     */
    public void testAddAll2() {
        Set full = populatedSet(3);
        // "one" is duplicate and will not be added
        assertTrue(full.addAll(Arrays.asList(three, four, one)));
        assertEquals(5, full.size());
        assertFalse(full.addAll(Arrays.asList(three, four, one)));
        assertEquals(5, full.size());
    }

    /**
     * add will not add the element if it already exists in the set
     */
    public void testAdd2() {
        Set full = populatedSet(3);
        full.add(one);
        assertEquals(3, full.size());
    }

    /**
     * add adds the element when it does not exist in the set
     */
    public void testAdd3() {
        Set full = populatedSet(3);
        full.add(three);
        assertTrue(full.contains(three));
    }

    /**
     * clear removes all elements from the set
     */
    public void testClear() {
        Collection full = populatedSet(3);
        full.clear();
        assertEquals(0, full.size());
        assertTrue(full.isEmpty());
    }

    /**
     * contains returns true for added elements
     */
    public void testContains() {
        Collection full = populatedSet(3);
        assertTrue(full.contains(one));
        assertFalse(full.contains(five));
    }

    /**
     * Sets with equal elements are equal
     */
    public void testEquals() {
        CopyOnWriteArraySet a = populatedSet(3);
        CopyOnWriteArraySet b = populatedSet(3);
        assertTrue(a.equals(b));
        assertTrue(b.equals(a));
        assertTrue(a.containsAll(b));
        assertTrue(b.containsAll(a));
        assertEquals(a.hashCode(), b.hashCode());
        assertEquals(a.size(), b.size());

        a.add(m1);
        assertFalse(a.equals(b));
        assertFalse(b.equals(a));
        assertTrue(a.containsAll(b));
        assertFalse(b.containsAll(a));
        b.add(m1);
        assertTrue(a.equals(b));
        assertTrue(b.equals(a));
        assertTrue(a.containsAll(b));
        assertTrue(b.containsAll(a));
        assertEquals(a.hashCode(), b.hashCode());

        Object x = a.iterator().next();
        a.remove(x);
        assertFalse(a.equals(b));
        assertFalse(b.equals(a));
        assertFalse(a.containsAll(b));
        assertTrue(b.containsAll(a));
        a.add(x);
        assertTrue(a.equals(b));
        assertTrue(b.equals(a));
        assertTrue(a.containsAll(b));
        assertTrue(b.containsAll(a));
        assertEquals(a.hashCode(), b.hashCode());
        assertEquals(a.size(), b.size());

        CopyOnWriteArraySet empty1 = new CopyOnWriteArraySet(Arrays.asList());
        CopyOnWriteArraySet empty2 = new CopyOnWriteArraySet(Arrays.asList());
        assertTrue(empty1.equals(empty1));
        assertTrue(empty1.equals(empty2));

        assertFalse(empty1.equals(a));
        assertFalse(a.equals(empty1));

        assertFalse(a.equals(null));
    }

    /**
     * containsAll returns true for collections with subset of elements
     */
    public void testContainsAll() {
        Collection full = populatedSet(3);
        assertTrue(full.containsAll(full));
        assertTrue(full.containsAll(Arrays.asList()));
        assertTrue(full.containsAll(Arrays.asList(one)));
        assertTrue(full.containsAll(Arrays.asList(one, two)));
        assertFalse(full.containsAll(Arrays.asList(one, two, six)));
        assertFalse(full.containsAll(Arrays.asList(six)));

        CopyOnWriteArraySet empty1 = new CopyOnWriteArraySet(Arrays.asList());
        CopyOnWriteArraySet empty2 = new CopyOnWriteArraySet(Arrays.asList());
        assertTrue(empty1.containsAll(empty2));
        assertTrue(empty1.containsAll(empty1));
        assertFalse(empty1.containsAll(full));
        assertTrue(full.containsAll(empty1));

        try {
            full.containsAll(null);
            shouldThrow();
        } catch (NullPointerException success) {}
    }

    /**
     * isEmpty is true when empty, else false
     */
    public void testIsEmpty() {
        assertTrue(populatedSet(0).isEmpty());
        assertFalse(populatedSet(3).isEmpty());
    }

    /**
     * iterator() returns an iterator containing the elements of the
     * set in insertion order
     */
    public void testIterator() {
        Collection empty = new CopyOnWriteArraySet();
        assertFalse(empty.iterator().hasNext());
        try {
            empty.iterator().next();
            shouldThrow();
        } catch (NoSuchElementException success) {}

        Integer[] elements = new Integer[SIZE];
        for (int i = 0; i < SIZE; i++)
            elements[i] = i;
        shuffle(elements);
        Collection<Integer> full = populatedSet(elements);

        Iterator it = full.iterator();
        for (int j = 0; j < SIZE; j++) {
            assertTrue(it.hasNext());
            assertEquals(elements[j], it.next());
        }
        assertIteratorExhausted(it);
    }

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

    /**
     * iterator remove is unsupported
     */
    public void testIteratorRemove() {
        Collection full = populatedSet(3);
        Iterator it = full.iterator();
        it.next();
        try {
            it.remove();
            shouldThrow();
        } catch (UnsupportedOperationException success) {}
    }

    /**
     * toString holds toString of elements
     */
    public void testToString() {
        assertEquals("[]", new CopyOnWriteArraySet().toString());
        Collection full = populatedSet(3);
        String s = full.toString();
        for (int i = 0; i < 3; ++i)
            assertTrue(s.contains(String.valueOf(i)));
        assertEquals(new ArrayList(full).toString(),
                     full.toString());
    }

    /**
     * removeAll removes all elements from the given collection
     */
    public void testRemoveAll() {
        Set full = populatedSet(3);
        assertTrue(full.removeAll(Arrays.asList(one, two)));
        assertEquals(1, full.size());
        assertFalse(full.removeAll(Arrays.asList(one, two)));
        assertEquals(1, full.size());
    }

    /**
     * remove removes an element
     */
    public void testRemove() {
        Collection full = populatedSet(3);
        full.remove(one);
        assertFalse(full.contains(one));
        assertEquals(2, full.size());
    }

    /**
     * size returns the number of elements
     */
    public void testSize() {
        Collection empty = new CopyOnWriteArraySet();
        Collection full = populatedSet(3);
        assertEquals(3, full.size());
        assertEquals(0, empty.size());
    }

    /**
     * toArray() returns an Object array containing all elements from
     * the set in insertion order
     */
    public void testToArray() {
        Object[] a = new CopyOnWriteArraySet().toArray();
        assertTrue(Arrays.equals(new Object[0], a));
        assertSame(Object[].class, a.getClass());

        Integer[] elements = new Integer[SIZE];
        for (int i = 0; i < SIZE; i++)
            elements[i] = i;
        shuffle(elements);
        Collection<Integer> full = populatedSet(elements);

        assertTrue(Arrays.equals(elements, full.toArray()));
        assertSame(Object[].class, full.toArray().getClass());
    }

    /**
     * toArray(Integer array) returns an Integer array containing all
     * elements from the set in insertion order
     */
    public void testToArray2() {
        Collection empty = new CopyOnWriteArraySet();
        Integer[] a;

        a = new Integer[0];
        assertSame(a, empty.toArray(a));

        a = new Integer[SIZE / 2];
        Arrays.fill(a, 42);
        assertSame(a, empty.toArray(a));
        assertNull(a[0]);
        for (int i = 1; i < a.length; i++)
            assertEquals(42, (int) a[i]);

        Integer[] elements = new Integer[SIZE];
        for (int i = 0; i < SIZE; i++)
            elements[i] = i;
        shuffle(elements);
        Collection<Integer> full = populatedSet(elements);

        Arrays.fill(a, 42);
        assertTrue(Arrays.equals(elements, full.toArray(a)));
        for (int i = 0; i < a.length; i++)
            assertEquals(42, (int) a[i]);
        assertSame(Integer[].class, full.toArray(a).getClass());

        a = new Integer[SIZE];
        Arrays.fill(a, 42);
        assertSame(a, full.toArray(a));
        assertTrue(Arrays.equals(elements, a));

        a = new Integer[2 * SIZE];
        Arrays.fill(a, 42);
        assertSame(a, full.toArray(a));
        assertTrue(Arrays.equals(elements, Arrays.copyOf(a, SIZE)));
        assertNull(a[SIZE]);
        for (int i = SIZE + 1; i < a.length; i++)
            assertEquals(42, (int) a[i]);
    }

    /**
     * toArray throws an ArrayStoreException when the given array can
     * not store the objects inside the set
     */
    public void testToArray_ArrayStoreException() {
        CopyOnWriteArraySet c = new CopyOnWriteArraySet();
        c.add("zfasdfsdf");
        c.add("asdadasd");
        try {
            c.toArray(new Long[5]);
            shouldThrow();
        } catch (ArrayStoreException success) {}
    }

    /**
     * A deserialized/reserialized set equals original
     */
    public void testSerialization() throws Exception {
        Set x = populatedSet(SIZE);
        Set y = serialClone(x);

        assertNotSame(y, x);
        assertEquals(x.size(), y.size());
        assertEquals(x.toString(), y.toString());
        assertTrue(Arrays.equals(x.toArray(), y.toArray()));
        assertEquals(x, y);
        assertEquals(y, x);
    }

    /**
     * addAll is idempotent
     */
    public void testAddAll_idempotent() throws Exception {
        Set x = populatedSet(SIZE);
        Set y = new CopyOnWriteArraySet(x);
        y.addAll(x);
        assertEquals(x, y);
        assertEquals(y, x);
    }

}
Revision:	1.41
Committed:	Tue May 8 00:25:33 2018 UTC (6 years ago) by jsr166
Branch:	MAIN
Changes since 1.40:	+0 -1 lines
Log Message:	remove unused import
#	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.ArrayList;
10	import java.util.Arrays;
11	import java.util.Collection;
12	import java.util.Iterator;
13	import java.util.NoSuchElementException;
14	import java.util.Set;
15	import java.util.concurrent.CopyOnWriteArraySet;
16
17	import junit.framework.Test;
18
19	public class CopyOnWriteArraySetTest extends JSR166TestCase {
20	public static void main(String[] args) {
21	main(suite(), args);
22	}
23	public static Test suite() {
24	class Implementation implements CollectionImplementation {
25	public Class<?> klazz() { return CopyOnWriteArraySet.class; }
26	public Set emptyCollection() { return new CopyOnWriteArraySet(); }
27	public Object makeElement(int i) { return i; }
28	public boolean isConcurrent() { return true; }
29	public boolean permitsNulls() { return true; }
30	}
31	return newTestSuite(
32	CopyOnWriteArraySetTest.class,
33	CollectionTest.testSuite(new Implementation()));
34	}
35
36	static CopyOnWriteArraySet<Integer> populatedSet(int n) {
37	CopyOnWriteArraySet<Integer> a = new CopyOnWriteArraySet<>();
38	assertTrue(a.isEmpty());
39	for (int i = 0; i < n; i++)
40	a.add(i);
41	assertEquals(n == 0, a.isEmpty());
42	assertEquals(n, a.size());
43	return a;
44	}
45
46	static CopyOnWriteArraySet populatedSet(Integer[] elements) {
47	CopyOnWriteArraySet<Integer> a = new CopyOnWriteArraySet<>();
48	assertTrue(a.isEmpty());
49	for (int i = 0; i < elements.length; i++)
50	a.add(elements[i]);
51	assertFalse(a.isEmpty());
52	assertEquals(elements.length, a.size());
53	return a;
54	}
55
56	/**
57	* Default-constructed set is empty
58	*/
59	public void testConstructor() {
60	CopyOnWriteArraySet a = new CopyOnWriteArraySet();
61	assertTrue(a.isEmpty());
62	}
63
64	/**
65	* Collection-constructed set holds all of its elements
66	*/
67	public void testConstructor3() {
68	Integer[] ints = new Integer[SIZE];
69	for (int i = 0; i < SIZE - 1; ++i)
70	ints[i] = new Integer(i);
71	CopyOnWriteArraySet a = new CopyOnWriteArraySet(Arrays.asList(ints));
72	for (int i = 0; i < SIZE; ++i)
73	assertTrue(a.contains(ints[i]));
74	}
75
76	/**
77	* addAll adds each non-duplicate element from the given collection
78	*/
79	public void testAddAll() {
80	Set full = populatedSet(3);
81	assertTrue(full.addAll(Arrays.asList(three, four, five)));
82	assertEquals(6, full.size());
83	assertFalse(full.addAll(Arrays.asList(three, four, five)));
84	assertEquals(6, full.size());
85	}
86
87	/**
88	* addAll adds each non-duplicate element from the given collection
89	*/
90	public void testAddAll2() {
91	Set full = populatedSet(3);
92	// "one" is duplicate and will not be added
93	assertTrue(full.addAll(Arrays.asList(three, four, one)));
94	assertEquals(5, full.size());
95	assertFalse(full.addAll(Arrays.asList(three, four, one)));
96	assertEquals(5, full.size());
97	}
98
99	/**
100	* add will not add the element if it already exists in the set
101	*/
102	public void testAdd2() {
103	Set full = populatedSet(3);
104	full.add(one);
105	assertEquals(3, full.size());
106	}
107
108	/**
109	* add adds the element when it does not exist in the set
110	*/
111	public void testAdd3() {
112	Set full = populatedSet(3);
113	full.add(three);
114	assertTrue(full.contains(three));
115	}
116
117	/**
118	* clear removes all elements from the set
119	*/
120	public void testClear() {
121	Collection full = populatedSet(3);
122	full.clear();
123	assertEquals(0, full.size());
124	assertTrue(full.isEmpty());
125	}
126
127	/**
128	* contains returns true for added elements
129	*/
130	public void testContains() {
131	Collection full = populatedSet(3);
132	assertTrue(full.contains(one));
133	assertFalse(full.contains(five));
134	}
135
136	/**
137	* Sets with equal elements are equal
138	*/
139	public void testEquals() {
140	CopyOnWriteArraySet a = populatedSet(3);
141	CopyOnWriteArraySet b = populatedSet(3);
142	assertTrue(a.equals(b));
143	assertTrue(b.equals(a));
144	assertTrue(a.containsAll(b));
145	assertTrue(b.containsAll(a));
146	assertEquals(a.hashCode(), b.hashCode());
147	assertEquals(a.size(), b.size());
148
149	a.add(m1);
150	assertFalse(a.equals(b));
151	assertFalse(b.equals(a));
152	assertTrue(a.containsAll(b));
153	assertFalse(b.containsAll(a));
154	b.add(m1);
155	assertTrue(a.equals(b));
156	assertTrue(b.equals(a));
157	assertTrue(a.containsAll(b));
158	assertTrue(b.containsAll(a));
159	assertEquals(a.hashCode(), b.hashCode());
160
161	Object x = a.iterator().next();
162	a.remove(x);
163	assertFalse(a.equals(b));
164	assertFalse(b.equals(a));
165	assertFalse(a.containsAll(b));
166	assertTrue(b.containsAll(a));
167	a.add(x);
168	assertTrue(a.equals(b));
169	assertTrue(b.equals(a));
170	assertTrue(a.containsAll(b));
171	assertTrue(b.containsAll(a));
172	assertEquals(a.hashCode(), b.hashCode());
173	assertEquals(a.size(), b.size());
174
175	CopyOnWriteArraySet empty1 = new CopyOnWriteArraySet(Arrays.asList());
176	CopyOnWriteArraySet empty2 = new CopyOnWriteArraySet(Arrays.asList());
177	assertTrue(empty1.equals(empty1));
178	assertTrue(empty1.equals(empty2));
179
180	assertFalse(empty1.equals(a));
181	assertFalse(a.equals(empty1));
182
183	assertFalse(a.equals(null));
184	}
185
186	/**
187	* containsAll returns true for collections with subset of elements
188	*/
189	public void testContainsAll() {
190	Collection full = populatedSet(3);
191	assertTrue(full.containsAll(full));
192	assertTrue(full.containsAll(Arrays.asList()));
193	assertTrue(full.containsAll(Arrays.asList(one)));
194	assertTrue(full.containsAll(Arrays.asList(one, two)));
195	assertFalse(full.containsAll(Arrays.asList(one, two, six)));
196	assertFalse(full.containsAll(Arrays.asList(six)));
197
198	CopyOnWriteArraySet empty1 = new CopyOnWriteArraySet(Arrays.asList());
199	CopyOnWriteArraySet empty2 = new CopyOnWriteArraySet(Arrays.asList());
200	assertTrue(empty1.containsAll(empty2));
201	assertTrue(empty1.containsAll(empty1));
202	assertFalse(empty1.containsAll(full));
203	assertTrue(full.containsAll(empty1));
204
205	try {
206	full.containsAll(null);
207	shouldThrow();
208	} catch (NullPointerException success) {}
209	}
210
211	/**
212	* isEmpty is true when empty, else false
213	*/
214	public void testIsEmpty() {
215	assertTrue(populatedSet(0).isEmpty());
216	assertFalse(populatedSet(3).isEmpty());
217	}
218
219	/**
220	* iterator() returns an iterator containing the elements of the
221	* set in insertion order
222	*/
223	public void testIterator() {
224	Collection empty = new CopyOnWriteArraySet();
225	assertFalse(empty.iterator().hasNext());
226	try {
227	empty.iterator().next();
228	shouldThrow();
229	} catch (NoSuchElementException success) {}
230
231	Integer[] elements = new Integer[SIZE];
232	for (int i = 0; i < SIZE; i++)
233	elements[i] = i;
234	shuffle(elements);
235	Collection<Integer> full = populatedSet(elements);
236
237	Iterator it = full.iterator();
238	for (int j = 0; j < SIZE; j++) {
239	assertTrue(it.hasNext());
240	assertEquals(elements[j], it.next());
241	}
242	assertIteratorExhausted(it);
243	}
244
245	/**
246	* iterator of empty collection has no elements
247	*/
248	public void testEmptyIterator() {
249	assertIteratorExhausted(new CopyOnWriteArraySet().iterator());
250	}
251
252	/**
253	* iterator remove is unsupported
254	*/
255	public void testIteratorRemove() {
256	Collection full = populatedSet(3);
257	Iterator it = full.iterator();
258	it.next();
259	try {
260	it.remove();
261	shouldThrow();
262	} catch (UnsupportedOperationException success) {}
263	}
264
265	/**
266	* toString holds toString of elements
267	*/
268	public void testToString() {
269	assertEquals("[]", new CopyOnWriteArraySet().toString());
270	Collection full = populatedSet(3);
271	String s = full.toString();
272	for (int i = 0; i < 3; ++i)
273	assertTrue(s.contains(String.valueOf(i)));
274	assertEquals(new ArrayList(full).toString(),
275	full.toString());
276	}
277
278	/**
279	* removeAll removes all elements from the given collection
280	*/
281	public void testRemoveAll() {
282	Set full = populatedSet(3);
283	assertTrue(full.removeAll(Arrays.asList(one, two)));
284	assertEquals(1, full.size());
285	assertFalse(full.removeAll(Arrays.asList(one, two)));
286	assertEquals(1, full.size());
287	}
288
289	/**
290	* remove removes an element
291	*/
292	public void testRemove() {
293	Collection full = populatedSet(3);
294	full.remove(one);
295	assertFalse(full.contains(one));
296	assertEquals(2, full.size());
297	}
298
299	/**
300	* size returns the number of elements
301	*/
302	public void testSize() {
303	Collection empty = new CopyOnWriteArraySet();
304	Collection full = populatedSet(3);
305	assertEquals(3, full.size());
306	assertEquals(0, empty.size());
307	}
308
309	/**
310	* toArray() returns an Object array containing all elements from
311	* the set in insertion order
312	*/
313	public void testToArray() {
314	Object[] a = new CopyOnWriteArraySet().toArray();
315	assertTrue(Arrays.equals(new Object[0], a));
316	assertSame(Object[].class, a.getClass());
317
318	Integer[] elements = new Integer[SIZE];
319	for (int i = 0; i < SIZE; i++)
320	elements[i] = i;
321	shuffle(elements);
322	Collection<Integer> full = populatedSet(elements);
323
324	assertTrue(Arrays.equals(elements, full.toArray()));
325	assertSame(Object[].class, full.toArray().getClass());
326	}
327
328	/**
329	* toArray(Integer array) returns an Integer array containing all
330	* elements from the set in insertion order
331	*/
332	public void testToArray2() {
333	Collection empty = new CopyOnWriteArraySet();
334	Integer[] a;
335
336	a = new Integer[0];
337	assertSame(a, empty.toArray(a));
338
339	a = new Integer[SIZE / 2];
340	Arrays.fill(a, 42);
341	assertSame(a, empty.toArray(a));
342	assertNull(a[0]);
343	for (int i = 1; i < a.length; i++)
344	assertEquals(42, (int) a[i]);
345
346	Integer[] elements = new Integer[SIZE];
347	for (int i = 0; i < SIZE; i++)
348	elements[i] = i;
349	shuffle(elements);
350	Collection<Integer> full = populatedSet(elements);
351
352	Arrays.fill(a, 42);
353	assertTrue(Arrays.equals(elements, full.toArray(a)));
354	for (int i = 0; i < a.length; i++)
355	assertEquals(42, (int) a[i]);
356	assertSame(Integer[].class, full.toArray(a).getClass());
357
358	a = new Integer[SIZE];
359	Arrays.fill(a, 42);
360	assertSame(a, full.toArray(a));
361	assertTrue(Arrays.equals(elements, a));
362
363	a = new Integer[2 * SIZE];
364	Arrays.fill(a, 42);
365	assertSame(a, full.toArray(a));
366	assertTrue(Arrays.equals(elements, Arrays.copyOf(a, SIZE)));
367	assertNull(a[SIZE]);
368	for (int i = SIZE + 1; i < a.length; i++)
369	assertEquals(42, (int) a[i]);
370	}
371
372	/**
373	* toArray throws an ArrayStoreException when the given array can
374	* not store the objects inside the set
375	*/
376	public void testToArray_ArrayStoreException() {
377	CopyOnWriteArraySet c = new CopyOnWriteArraySet();
378	c.add("zfasdfsdf");
379	c.add("asdadasd");
380	try {
381	c.toArray(new Long[5]);
382	shouldThrow();
383	} catch (ArrayStoreException success) {}
384	}
385
386	/**
387	* A deserialized/reserialized set equals original
388	*/
389	public void testSerialization() throws Exception {
390	Set x = populatedSet(SIZE);
391	Set y = serialClone(x);
392
393	assertNotSame(y, x);
394	assertEquals(x.size(), y.size());
395	assertEquals(x.toString(), y.toString());
396	assertTrue(Arrays.equals(x.toArray(), y.toArray()));
397	assertEquals(x, y);
398	assertEquals(y, x);
399	}
400
401	/**
402	* addAll is idempotent
403	*/
404	public void testAddAll_idempotent() throws Exception {
405	Set x = populatedSet(SIZE);
406	Set y = new CopyOnWriteArraySet(x);
407	y.addAll(x);
408	assertEquals(x, y);
409	assertEquals(y, x);
410	}
411
412	}