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;
import junit.framework.TestSuite;

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:	1.40
Committed:	Thu Apr 5 02:20:21 2018 UTC (6 years, 1 month ago) by jsr166
Branch:	MAIN
Changes since 1.39:	+10 -1 lines
Log Message:	test CopyOnWriteArraySet with CollectionTest infrastrure
#	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	import junit.framework.TestSuite;
19
20	public class CopyOnWriteArraySetTest extends JSR166TestCase {
21	public static void main(String[] args) {
22	main(suite(), args);
23	}
24	public static Test suite() {
25	class Implementation implements CollectionImplementation {
26	public Class<?> klazz() { return CopyOnWriteArraySet.class; }
27	public Set emptyCollection() { return new CopyOnWriteArraySet(); }
28	public Object makeElement(int i) { return i; }
29	public boolean isConcurrent() { return true; }
30	public boolean permitsNulls() { return true; }
31	}
32	return newTestSuite(
33	CopyOnWriteArraySetTest.class,
34	CollectionTest.testSuite(new Implementation()));
35	}
36
37	static CopyOnWriteArraySet<Integer> populatedSet(int n) {
38	CopyOnWriteArraySet<Integer> a = new CopyOnWriteArraySet<>();
39	assertTrue(a.isEmpty());
40	for (int i = 0; i < n; i++)
41	a.add(i);
42	assertEquals(n == 0, a.isEmpty());
43	assertEquals(n, a.size());
44	return a;
45	}
46
47	static CopyOnWriteArraySet populatedSet(Integer[] elements) {
48	CopyOnWriteArraySet<Integer> a = new CopyOnWriteArraySet<>();
49	assertTrue(a.isEmpty());
50	for (int i = 0; i < elements.length; i++)
51	a.add(elements[i]);
52	assertFalse(a.isEmpty());
53	assertEquals(elements.length, a.size());
54	return a;
55	}
56
57	/**
58	* Default-constructed set is empty
59	*/
60	public void testConstructor() {
61	CopyOnWriteArraySet a = new CopyOnWriteArraySet();
62	assertTrue(a.isEmpty());
63	}
64
65	/**
66	* Collection-constructed set holds all of its elements
67	*/
68	public void testConstructor3() {
69	Integer[] ints = new Integer[SIZE];
70	for (int i = 0; i < SIZE - 1; ++i)
71	ints[i] = new Integer(i);
72	CopyOnWriteArraySet a = new CopyOnWriteArraySet(Arrays.asList(ints));
73	for (int i = 0; i < SIZE; ++i)
74	assertTrue(a.contains(ints[i]));
75	}
76
77	/**
78	* addAll adds each non-duplicate element from the given collection
79	*/
80	public void testAddAll() {
81	Set full = populatedSet(3);
82	assertTrue(full.addAll(Arrays.asList(three, four, five)));
83	assertEquals(6, full.size());
84	assertFalse(full.addAll(Arrays.asList(three, four, five)));
85	assertEquals(6, full.size());
86	}
87
88	/**
89	* addAll adds each non-duplicate element from the given collection
90	*/
91	public void testAddAll2() {
92	Set full = populatedSet(3);
93	// "one" is duplicate and will not be added
94	assertTrue(full.addAll(Arrays.asList(three, four, one)));
95	assertEquals(5, full.size());
96	assertFalse(full.addAll(Arrays.asList(three, four, one)));
97	assertEquals(5, full.size());
98	}
99
100	/**
101	* add will not add the element if it already exists in the set
102	*/
103	public void testAdd2() {
104	Set full = populatedSet(3);
105	full.add(one);
106	assertEquals(3, full.size());
107	}
108
109	/**
110	* add adds the element when it does not exist in the set
111	*/
112	public void testAdd3() {
113	Set full = populatedSet(3);
114	full.add(three);
115	assertTrue(full.contains(three));
116	}
117
118	/**
119	* clear removes all elements from the set
120	*/
121	public void testClear() {
122	Collection full = populatedSet(3);
123	full.clear();
124	assertEquals(0, full.size());
125	assertTrue(full.isEmpty());
126	}
127
128	/**
129	* contains returns true for added elements
130	*/
131	public void testContains() {
132	Collection full = populatedSet(3);
133	assertTrue(full.contains(one));
134	assertFalse(full.contains(five));
135	}
136
137	/**
138	* Sets with equal elements are equal
139	*/
140	public void testEquals() {
141	CopyOnWriteArraySet a = populatedSet(3);
142	CopyOnWriteArraySet b = populatedSet(3);
143	assertTrue(a.equals(b));
144	assertTrue(b.equals(a));
145	assertTrue(a.containsAll(b));
146	assertTrue(b.containsAll(a));
147	assertEquals(a.hashCode(), b.hashCode());
148	assertEquals(a.size(), b.size());
149
150	a.add(m1);
151	assertFalse(a.equals(b));
152	assertFalse(b.equals(a));
153	assertTrue(a.containsAll(b));
154	assertFalse(b.containsAll(a));
155	b.add(m1);
156	assertTrue(a.equals(b));
157	assertTrue(b.equals(a));
158	assertTrue(a.containsAll(b));
159	assertTrue(b.containsAll(a));
160	assertEquals(a.hashCode(), b.hashCode());
161
162	Object x = a.iterator().next();
163	a.remove(x);
164	assertFalse(a.equals(b));
165	assertFalse(b.equals(a));
166	assertFalse(a.containsAll(b));
167	assertTrue(b.containsAll(a));
168	a.add(x);
169	assertTrue(a.equals(b));
170	assertTrue(b.equals(a));
171	assertTrue(a.containsAll(b));
172	assertTrue(b.containsAll(a));
173	assertEquals(a.hashCode(), b.hashCode());
174	assertEquals(a.size(), b.size());
175
176	CopyOnWriteArraySet empty1 = new CopyOnWriteArraySet(Arrays.asList());
177	CopyOnWriteArraySet empty2 = new CopyOnWriteArraySet(Arrays.asList());
178	assertTrue(empty1.equals(empty1));
179	assertTrue(empty1.equals(empty2));
180
181	assertFalse(empty1.equals(a));
182	assertFalse(a.equals(empty1));
183
184	assertFalse(a.equals(null));
185	}
186
187	/**
188	* containsAll returns true for collections with subset of elements
189	*/
190	public void testContainsAll() {
191	Collection full = populatedSet(3);
192	assertTrue(full.containsAll(full));
193	assertTrue(full.containsAll(Arrays.asList()));
194	assertTrue(full.containsAll(Arrays.asList(one)));
195	assertTrue(full.containsAll(Arrays.asList(one, two)));
196	assertFalse(full.containsAll(Arrays.asList(one, two, six)));
197	assertFalse(full.containsAll(Arrays.asList(six)));
198
199	CopyOnWriteArraySet empty1 = new CopyOnWriteArraySet(Arrays.asList());
200	CopyOnWriteArraySet empty2 = new CopyOnWriteArraySet(Arrays.asList());
201	assertTrue(empty1.containsAll(empty2));
202	assertTrue(empty1.containsAll(empty1));
203	assertFalse(empty1.containsAll(full));
204	assertTrue(full.containsAll(empty1));
205
206	try {
207	full.containsAll(null);
208	shouldThrow();
209	} catch (NullPointerException success) {}
210	}
211
212	/**
213	* isEmpty is true when empty, else false
214	*/
215	public void testIsEmpty() {
216	assertTrue(populatedSet(0).isEmpty());
217	assertFalse(populatedSet(3).isEmpty());
218	}
219
220	/**
221	* iterator() returns an iterator containing the elements of the
222	* set in insertion order
223	*/
224	public void testIterator() {
225	Collection empty = new CopyOnWriteArraySet();
226	assertFalse(empty.iterator().hasNext());
227	try {
228	empty.iterator().next();
229	shouldThrow();
230	} catch (NoSuchElementException success) {}
231
232	Integer[] elements = new Integer[SIZE];
233	for (int i = 0; i < SIZE; i++)
234	elements[i] = i;
235	shuffle(elements);
236	Collection<Integer> full = populatedSet(elements);
237
238	Iterator it = full.iterator();
239	for (int j = 0; j < SIZE; j++) {
240	assertTrue(it.hasNext());
241	assertEquals(elements[j], it.next());
242	}
243	assertIteratorExhausted(it);
244	}
245
246	/**
247	* iterator of empty collection has no elements
248	*/
249	public void testEmptyIterator() {
250	assertIteratorExhausted(new CopyOnWriteArraySet().iterator());
251	}
252
253	/**
254	* iterator remove is unsupported
255	*/
256	public void testIteratorRemove() {
257	Collection full = populatedSet(3);
258	Iterator it = full.iterator();
259	it.next();
260	try {
261	it.remove();
262	shouldThrow();
263	} catch (UnsupportedOperationException success) {}
264	}
265
266	/**
267	* toString holds toString of elements
268	*/
269	public void testToString() {
270	assertEquals("[]", new CopyOnWriteArraySet().toString());
271	Collection full = populatedSet(3);
272	String s = full.toString();
273	for (int i = 0; i < 3; ++i)
274	assertTrue(s.contains(String.valueOf(i)));
275	assertEquals(new ArrayList(full).toString(),
276	full.toString());
277	}
278
279	/**
280	* removeAll removes all elements from the given collection
281	*/
282	public void testRemoveAll() {
283	Set full = populatedSet(3);
284	assertTrue(full.removeAll(Arrays.asList(one, two)));
285	assertEquals(1, full.size());
286	assertFalse(full.removeAll(Arrays.asList(one, two)));
287	assertEquals(1, full.size());
288	}
289
290	/**
291	* remove removes an element
292	*/
293	public void testRemove() {
294	Collection full = populatedSet(3);
295	full.remove(one);
296	assertFalse(full.contains(one));
297	assertEquals(2, full.size());
298	}
299
300	/**
301	* size returns the number of elements
302	*/
303	public void testSize() {
304	Collection empty = new CopyOnWriteArraySet();
305	Collection full = populatedSet(3);
306	assertEquals(3, full.size());
307	assertEquals(0, empty.size());
308	}
309
310	/**
311	* toArray() returns an Object array containing all elements from
312	* the set in insertion order
313	*/
314	public void testToArray() {
315	Object[] a = new CopyOnWriteArraySet().toArray();
316	assertTrue(Arrays.equals(new Object[0], a));
317	assertSame(Object[].class, a.getClass());
318
319	Integer[] elements = new Integer[SIZE];
320	for (int i = 0; i < SIZE; i++)
321	elements[i] = i;
322	shuffle(elements);
323	Collection<Integer> full = populatedSet(elements);
324
325	assertTrue(Arrays.equals(elements, full.toArray()));
326	assertSame(Object[].class, full.toArray().getClass());
327	}
328
329	/**
330	* toArray(Integer array) returns an Integer array containing all
331	* elements from the set in insertion order
332	*/
333	public void testToArray2() {
334	Collection empty = new CopyOnWriteArraySet();
335	Integer[] a;
336
337	a = new Integer[0];
338	assertSame(a, empty.toArray(a));
339
340	a = new Integer[SIZE / 2];
341	Arrays.fill(a, 42);
342	assertSame(a, empty.toArray(a));
343	assertNull(a[0]);
344	for (int i = 1; i < a.length; i++)
345	assertEquals(42, (int) a[i]);
346
347	Integer[] elements = new Integer[SIZE];
348	for (int i = 0; i < SIZE; i++)
349	elements[i] = i;
350	shuffle(elements);
351	Collection<Integer> full = populatedSet(elements);
352
353	Arrays.fill(a, 42);
354	assertTrue(Arrays.equals(elements, full.toArray(a)));
355	for (int i = 0; i < a.length; i++)
356	assertEquals(42, (int) a[i]);
357	assertSame(Integer[].class, full.toArray(a).getClass());
358
359	a = new Integer[SIZE];
360	Arrays.fill(a, 42);
361	assertSame(a, full.toArray(a));
362	assertTrue(Arrays.equals(elements, a));
363
364	a = new Integer[2 * SIZE];
365	Arrays.fill(a, 42);
366	assertSame(a, full.toArray(a));
367	assertTrue(Arrays.equals(elements, Arrays.copyOf(a, SIZE)));
368	assertNull(a[SIZE]);
369	for (int i = SIZE + 1; i < a.length; i++)
370	assertEquals(42, (int) a[i]);
371	}
372
373	/**
374	* toArray throws an ArrayStoreException when the given array can
375	* not store the objects inside the set
376	*/
377	public void testToArray_ArrayStoreException() {
378	CopyOnWriteArraySet c = new CopyOnWriteArraySet();
379	c.add("zfasdfsdf");
380	c.add("asdadasd");
381	try {
382	c.toArray(new Long[5]);
383	shouldThrow();
384	} catch (ArrayStoreException success) {}
385	}
386
387	/**
388	* A deserialized/reserialized set equals original
389	*/
390	public void testSerialization() throws Exception {
391	Set x = populatedSet(SIZE);
392	Set y = serialClone(x);
393
394	assertNotSame(y, x);
395	assertEquals(x.size(), y.size());
396	assertEquals(x.toString(), y.toString());
397	assertTrue(Arrays.equals(x.toArray(), y.toArray()));
398	assertEquals(x, y);
399	assertEquals(y, x);
400	}
401
402	/**
403	* addAll is idempotent
404	*/
405	public void testAddAll_idempotent() throws Exception {
406	Set x = populatedSet(SIZE);
407	Set y = new CopyOnWriteArraySet(x);
408	y.addAll(x);
409	assertEquals(x, y);
410	assertEquals(y, x);
411	}
412
413	}