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.Collections;
import java.util.Iterator;
import java.util.NoSuchElementException;
import java.util.Set;
import java.util.Vector;
import java.util.concurrent.CopyOnWriteArraySet;

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

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

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

    static CopyOnWriteArraySet populatedSet(Integer[] elements) {
        CopyOnWriteArraySet<Integer> a = new CopyOnWriteArraySet<Integer>();
        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 element from the given collection
     */
    public void testAddAll() {
        CopyOnWriteArraySet full = populatedSet(3);
        Vector v = new Vector();
        v.add(three);
        v.add(four);
        v.add(five);
        full.addAll(v);
        assertEquals(6, full.size());
    }

    /**
     * addAll adds each element from the given collection that did not
     * already exist in the set
     */
    public void testAddAll2() {
        CopyOnWriteArraySet full = populatedSet(3);
        Vector v = new Vector();
        v.add(three);
        v.add(four);
        v.add(one); // will not add this element
        full.addAll(v);
        assertEquals(5, full.size());
    }

    /**
     * add will not add the element if it already exists in the set
     */
    public void testAdd2() {
        CopyOnWriteArraySet 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() {
        CopyOnWriteArraySet full = populatedSet(3);
        full.add(three);
        assertTrue(full.contains(three));
    }

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

    /**
     * contains returns true for added elements
     */
    public void testContains() {
        CopyOnWriteArraySet 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));
        assertEquals(a.hashCode(), b.hashCode());
        a.add(m1);
        assertFalse(a.equals(b));
        assertFalse(b.equals(a));
        b.add(m1);
        assertTrue(a.equals(b));
        assertTrue(b.equals(a));
        assertEquals(a.hashCode(), b.hashCode());
    }

    /**
     * containsAll returns true for collections with subset of elements
     */
    public void testContainsAll() {
        CopyOnWriteArraySet full = populatedSet(3);
        Vector v = new Vector();
        v.add(one);
        v.add(two);
        assertTrue(full.containsAll(v));
        v.add(six);
        assertFalse(full.containsAll(v));
    }

    /**
     * isEmpty is true when empty, else false
     */
    public void testIsEmpty() {
        CopyOnWriteArraySet empty = new CopyOnWriteArraySet();
        CopyOnWriteArraySet full = populatedSet(3);
        assertTrue(empty.isEmpty());
        assertFalse(full.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;
        Collections.shuffle(Arrays.asList(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());
        }
        assertFalse(it.hasNext());
        try {
            it.next();
            shouldThrow();
        } catch (NoSuchElementException success) {}
    }

    /**
     * iterator remove is unsupported
     */
    public void testIteratorRemove() {
        CopyOnWriteArraySet 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());
        CopyOnWriteArraySet 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() {
        CopyOnWriteArraySet full = populatedSet(3);
        Vector v = new Vector();
        v.add(one);
        v.add(two);
        full.removeAll(v);
        assertEquals(1, full.size());
    }

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

    /**
     * size returns the number of elements
     */
    public void testSize() {
        CopyOnWriteArraySet empty = new CopyOnWriteArraySet();
        CopyOnWriteArraySet 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;
        Collections.shuffle(Arrays.asList(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;
        Collections.shuffle(Arrays.asList(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() {
        try {
            CopyOnWriteArraySet c = new CopyOnWriteArraySet();
            c.add("zfasdfsdf");
            c.add("asdadasd");
            c.toArray(new Long[5]);
            shouldThrow();
        } catch (ArrayStoreException success) {}
    }

    /**
     * A deserialized serialized set is equal
     */
    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:	1.28
Committed:	Wed Dec 31 19:05:42 2014 UTC (9 years, 4 months ago) by jsr166
Branch:	MAIN
Changes since 1.27:	+3 -1 lines
Log Message:	no wildcard imports
#	User	Rev	Content
1	dl	1.1	/*
2	dl	1.6	* 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	jsr166	1.17	* http://creativecommons.org/publicdomain/zero/1.0/
5	jsr166	1.8	* Other contributors include Andrew Wright, Jeffrey Hayes,
6			* Pat Fisher, Mike Judd.
7	dl	1.1	*/
8
9	jsr166	1.25	import java.util.ArrayList;
10	jsr166	1.19	import java.util.Arrays;
11	jsr166	1.22	import java.util.Collection;
12	jsr166	1.21	import java.util.Collections;
13	jsr166	1.19	import java.util.Iterator;
14	jsr166	1.24	import java.util.NoSuchElementException;
15	jsr166	1.19	import java.util.Set;
16			import java.util.Vector;
17			import java.util.concurrent.CopyOnWriteArraySet;
18	dl	1.1
19	jsr166	1.28	import junit.framework.Test;
20			import junit.framework.TestSuite;
21
22	dl	1.3	public class CopyOnWriteArraySetTest extends JSR166TestCase {
23	dl	1.1	public static void main(String[] args) {
24	jsr166	1.15	junit.textui.TestRunner.run(suite());
25	dl	1.1	}
26			public static Test suite() {
27	jsr166	1.11	return new TestSuite(CopyOnWriteArraySetTest.class);
28	dl	1.1	}
29
30	jsr166	1.21	static CopyOnWriteArraySet<Integer> populatedSet(int n) {
31			CopyOnWriteArraySet<Integer> a = new CopyOnWriteArraySet<Integer>();
32	dl	1.1	assertTrue(a.isEmpty());
33	jsr166	1.22	for (int i = 0; i < n; i++)
34	jsr166	1.21	a.add(i);
35	dl	1.1	assertFalse(a.isEmpty());
36			assertEquals(n, a.size());
37			return a;
38			}
39
40	jsr166	1.21	static CopyOnWriteArraySet populatedSet(Integer[] elements) {
41			CopyOnWriteArraySet<Integer> a = new CopyOnWriteArraySet<Integer>();
42			assertTrue(a.isEmpty());
43			for (int i = 0; i < elements.length; i++)
44			a.add(elements[i]);
45			assertFalse(a.isEmpty());
46			assertEquals(elements.length, a.size());
47			return a;
48			}
49
50	dl	1.4	/**
51			* Default-constructed set is empty
52			*/
53	dl	1.3	public void testConstructor() {
54	jsr166	1.11	CopyOnWriteArraySet a = new CopyOnWriteArraySet();
55	dl	1.3	assertTrue(a.isEmpty());
56			}
57
58	dl	1.4	/**
59	dl	1.5	* Collection-constructed set holds all of its elements
60	dl	1.4	*/
61	dl	1.3	public void testConstructor3() {
62			Integer[] ints = new Integer[SIZE];
63			for (int i = 0; i < SIZE-1; ++i)
64			ints[i] = new Integer(i);
65	jsr166	1.11	CopyOnWriteArraySet a = new CopyOnWriteArraySet(Arrays.asList(ints));
66	jsr166	1.8	for (int i = 0; i < SIZE; ++i)
67	dl	1.3	assertTrue(a.contains(ints[i]));
68			}
69	jsr166	1.8
70	dl	1.1	/**
71	jsr166	1.16	* addAll adds each element from the given collection
72	dl	1.1	*/
73	dl	1.4	public void testAddAll() {
74	jsr166	1.11	CopyOnWriteArraySet full = populatedSet(3);
75			Vector v = new Vector();
76			v.add(three);
77			v.add(four);
78			v.add(five);
79			full.addAll(v);
80			assertEquals(6, full.size());
81	dl	1.1	}
82
83			/**
84	jsr166	1.16	* addAll adds each element from the given collection that did not
85			* already exist in the set
86	dl	1.1	*/
87	dl	1.4	public void testAddAll2() {
88	jsr166	1.11	CopyOnWriteArraySet full = populatedSet(3);
89			Vector v = new Vector();
90			v.add(three);
91			v.add(four);
92			v.add(one); // will not add this element
93			full.addAll(v);
94			assertEquals(5, full.size());
95	dl	1.1	}
96
97			/**
98	jsr166	1.16	* add will not add the element if it already exists in the set
99	dl	1.1	*/
100	dl	1.4	public void testAdd2() {
101	jsr166	1.11	CopyOnWriteArraySet full = populatedSet(3);
102			full.add(one);
103			assertEquals(3, full.size());
104	dl	1.1	}
105
106			/**
107	jsr166	1.16	* add adds the element when it does not exist in the set
108	dl	1.1	*/
109	dl	1.4	public void testAdd3() {
110	jsr166	1.11	CopyOnWriteArraySet full = populatedSet(3);
111	dl	1.3	full.add(three);
112			assertTrue(full.contains(three));
113	dl	1.1	}
114
115			/**
116	jsr166	1.16	* clear removes all elements from the set
117	dl	1.1	*/
118	dl	1.4	public void testClear() {
119	jsr166	1.11	CopyOnWriteArraySet full = populatedSet(3);
120			full.clear();
121			assertEquals(0, full.size());
122	dl	1.1	}
123
124			/**
125	jsr166	1.16	* contains returns true for added elements
126	dl	1.1	*/
127	dl	1.4	public void testContains() {
128	jsr166	1.11	CopyOnWriteArraySet full = populatedSet(3);
129			assertTrue(full.contains(one));
130			assertFalse(full.contains(five));
131	dl	1.1	}
132
133	dl	1.4	/**
134			* Sets with equal elements are equal
135			*/
136	dl	1.1	public void testEquals() {
137	jsr166	1.11	CopyOnWriteArraySet a = populatedSet(3);
138			CopyOnWriteArraySet b = populatedSet(3);
139	dl	1.1	assertTrue(a.equals(b));
140			assertTrue(b.equals(a));
141			assertEquals(a.hashCode(), b.hashCode());
142	dl	1.3	a.add(m1);
143	dl	1.1	assertFalse(a.equals(b));
144			assertFalse(b.equals(a));
145	dl	1.3	b.add(m1);
146	dl	1.1	assertTrue(a.equals(b));
147			assertTrue(b.equals(a));
148			assertEquals(a.hashCode(), b.hashCode());
149			}
150
151			/**
152	jsr166	1.16	* containsAll returns true for collections with subset of elements
153	dl	1.1	*/
154	dl	1.4	public void testContainsAll() {
155	jsr166	1.11	CopyOnWriteArraySet full = populatedSet(3);
156			Vector v = new Vector();
157			v.add(one);
158			v.add(two);
159			assertTrue(full.containsAll(v));
160			v.add(six);
161			assertFalse(full.containsAll(v));
162	dl	1.1	}
163
164			/**
165	jsr166	1.16	* isEmpty is true when empty, else false
166	dl	1.1	*/
167	dl	1.4	public void testIsEmpty() {
168	jsr166	1.11	CopyOnWriteArraySet empty = new CopyOnWriteArraySet();
169			CopyOnWriteArraySet full = populatedSet(3);
170			assertTrue(empty.isEmpty());
171			assertFalse(full.isEmpty());
172	dl	1.1	}
173
174			/**
175	jsr166	1.24	* iterator() returns an iterator containing the elements of the
176			* set in insertion order
177	dl	1.1	*/
178	dl	1.4	public void testIterator() {
179	jsr166	1.25	Collection empty = new CopyOnWriteArraySet();
180	jsr166	1.24	assertFalse(empty.iterator().hasNext());
181			try {
182			empty.iterator().next();
183			shouldThrow();
184			} catch (NoSuchElementException success) {}
185
186			Integer[] elements = new Integer[SIZE];
187			for (int i = 0; i < SIZE; i++)
188			elements[i] = i;
189			Collections.shuffle(Arrays.asList(elements));
190			Collection<Integer> full = populatedSet(elements);
191
192			Iterator it = full.iterator();
193			for (int j = 0; j < SIZE; j++) {
194			assertTrue(it.hasNext());
195			assertEquals(elements[j], it.next());
196			}
197			assertFalse(it.hasNext());
198			try {
199			it.next();
200			shouldThrow();
201			} catch (NoSuchElementException success) {}
202	dl	1.1	}
203
204	dl	1.4	/**
205			* iterator remove is unsupported
206			*/
207	jsr166	1.15	public void testIteratorRemove() {
208	jsr166	1.11	CopyOnWriteArraySet full = populatedSet(3);
209	dl	1.1	Iterator it = full.iterator();
210			it.next();
211			try {
212			it.remove();
213	dl	1.4	shouldThrow();
214	jsr166	1.12	} catch (UnsupportedOperationException success) {}
215	dl	1.1	}
216
217	dl	1.4	/**
218			* toString holds toString of elements
219			*/
220			public void testToString() {
221	jsr166	1.25	assertEquals("[]", new CopyOnWriteArraySet().toString());
222	jsr166	1.11	CopyOnWriteArraySet full = populatedSet(3);
223	dl	1.1	String s = full.toString();
224	jsr166	1.25	for (int i = 0; i < 3; ++i)
225	jsr166	1.18	assertTrue(s.contains(String.valueOf(i)));
226	jsr166	1.25	assertEquals(new ArrayList(full).toString(),
227			full.toString());
228	jsr166	1.8	}
229	dl	1.1
230			/**
231	jsr166	1.16	* removeAll removes all elements from the given collection
232	dl	1.1	*/
233	dl	1.4	public void testRemoveAll() {
234	jsr166	1.11	CopyOnWriteArraySet full = populatedSet(3);
235			Vector v = new Vector();
236			v.add(one);
237			v.add(two);
238			full.removeAll(v);
239			assertEquals(1, full.size());
240	dl	1.1	}
241
242	dl	1.4	/**
243			* remove removes an element
244			*/
245			public void testRemove() {
246	jsr166	1.11	CopyOnWriteArraySet full = populatedSet(3);
247			full.remove(one);
248	dl	1.3	assertFalse(full.contains(one));
249	jsr166	1.11	assertEquals(2, full.size());
250	dl	1.1	}
251
252			/**
253	jsr166	1.16	* size returns the number of elements
254	dl	1.1	*/
255	dl	1.4	public void testSize() {
256	jsr166	1.11	CopyOnWriteArraySet empty = new CopyOnWriteArraySet();
257			CopyOnWriteArraySet full = populatedSet(3);
258			assertEquals(3, full.size());
259			assertEquals(0, empty.size());
260	dl	1.1	}
261
262			/**
263	jsr166	1.21	* toArray() returns an Object array containing all elements from
264			* the set in insertion order
265	dl	1.1	*/
266	dl	1.4	public void testToArray() {
267	jsr166	1.21	Object[] a = new CopyOnWriteArraySet().toArray();
268			assertTrue(Arrays.equals(new Object[0], a));
269			assertSame(Object[].class, a.getClass());
270
271			Integer[] elements = new Integer[SIZE];
272	jsr166	1.20	for (int i = 0; i < SIZE; i++)
273	jsr166	1.21	elements[i] = i;
274			Collections.shuffle(Arrays.asList(elements));
275	jsr166	1.22	Collection<Integer> full = populatedSet(elements);
276	jsr166	1.21
277			assertTrue(Arrays.equals(elements, full.toArray()));
278			assertSame(Object[].class, full.toArray().getClass());
279	dl	1.1	}
280
281			/**
282	jsr166	1.21	* toArray(Integer array) returns an Integer array containing all
283			* elements from the set in insertion order
284	dl	1.1	*/
285	dl	1.4	public void testToArray2() {
286	jsr166	1.22	Collection empty = new CopyOnWriteArraySet();
287	jsr166	1.21	Integer[] a;
288
289			a = new Integer[0];
290			assertSame(a, empty.toArray(a));
291
292			a = new Integer[SIZE/2];
293			Arrays.fill(a, 42);
294			assertSame(a, empty.toArray(a));
295			assertNull(a[0]);
296			for (int i = 1; i < a.length; i++)
297			assertEquals(42, (int) a[i]);
298
299			Integer[] elements = new Integer[SIZE];
300	jsr166	1.20	for (int i = 0; i < SIZE; i++)
301	jsr166	1.21	elements[i] = i;
302			Collections.shuffle(Arrays.asList(elements));
303	jsr166	1.22	Collection<Integer> full = populatedSet(elements);
304	jsr166	1.21
305			Arrays.fill(a, 42);
306			assertTrue(Arrays.equals(elements, full.toArray(a)));
307			for (int i = 0; i < a.length; i++)
308			assertEquals(42, (int) a[i]);
309			assertSame(Integer[].class, full.toArray(a).getClass());
310
311			a = new Integer[SIZE];
312			Arrays.fill(a, 42);
313			assertSame(a, full.toArray(a));
314			assertTrue(Arrays.equals(elements, a));
315
316			a = new Integer[2*SIZE];
317			Arrays.fill(a, 42);
318			assertSame(a, full.toArray(a));
319			assertTrue(Arrays.equals(elements, Arrays.copyOf(a, SIZE)));
320			assertNull(a[SIZE]);
321			for (int i = SIZE + 1; i < a.length; i++)
322			assertEquals(42, (int) a[i]);
323	dl	1.1	}
324
325			/**
326	jsr166	1.16	* toArray throws an ArrayStoreException when the given array can
327			* not store the objects inside the set
328	dl	1.1	*/
329	dl	1.4	public void testToArray_ArrayStoreException() {
330			try {
331	dl	1.1	CopyOnWriteArraySet c = new CopyOnWriteArraySet();
332			c.add("zfasdfsdf");
333			c.add("asdadasd");
334			c.toArray(new Long[5]);
335	jsr166	1.11	shouldThrow();
336	jsr166	1.13	} catch (ArrayStoreException success) {}
337	dl	1.2	}
338
339	dl	1.4	/**
340	dl	1.7	* A deserialized serialized set is equal
341	dl	1.4	*/
342	jsr166	1.12	public void testSerialization() throws Exception {
343	jsr166	1.19	Set x = populatedSet(SIZE);
344			Set y = serialClone(x);
345	dl	1.2
346	jsr166	1.27	assertNotSame(y, x);
347	jsr166	1.19	assertEquals(x.size(), y.size());
348	jsr166	1.23	assertEquals(x.toString(), y.toString());
349			assertTrue(Arrays.equals(x.toArray(), y.toArray()));
350	jsr166	1.19	assertEquals(x, y);
351			assertEquals(y, x);
352	dl	1.1	}
353
354	jsr166	1.26	/**
355			* addAll is idempotent
356			*/
357			public void testAddAll_idempotent() throws Exception {
358			Set x = populatedSet(SIZE);
359			Set y = new CopyOnWriteArraySet(x);
360			y.addAll(x);
361			assertEquals(x, y);
362			assertEquals(y, x);
363			}
364
365	dl	1.1	}