test/tck/LinkedListTest.java

/*
 * Written by Doug Lea with assistance from members of JCP JSR-166
 * Expert Group and released to the public domain, as explained at
 * http://creativecommons.org/publicdomain/zero/1.0/
 * Other contributors include Andrew Wright, Jeffrey Hayes,
 * Pat Fisher, Mike Judd.
 */

import java.util.Arrays;
import java.util.Collection;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.NoSuchElementException;

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

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

    public static Test suite() {
        return new TestSuite(LinkedListTest.class);
    }

    /**
     * Returns a new queue of given size containing consecutive
     * Integers 0 ... n.
     */
    private LinkedList<Integer> populatedQueue(int n) {
        LinkedList<Integer> q = new LinkedList<Integer>();
        assertTrue(q.isEmpty());
        for (int i = 0; i < n; ++i)
            assertTrue(q.offer(new Integer(i)));
        assertFalse(q.isEmpty());
        assertEquals(n, q.size());
        return q;
    }

    /**
     * new queue is empty
     */
    public void testConstructor1() {
        assertEquals(0, new LinkedList().size());
    }

    /**
     * Initializing from null Collection throws NPE
     */
    public void testConstructor3() {
        try {
            new LinkedList((Collection)null);
            shouldThrow();
        } catch (NullPointerException success) {}
    }

    /**
     * Queue contains all elements of collection used to initialize
     */
    public void testConstructor6() {
        Integer[] ints = new Integer[SIZE];
        for (int i = 0; i < SIZE; ++i)
            ints[i] = i;
        LinkedList q = new LinkedList(Arrays.asList(ints));
        for (int i = 0; i < SIZE; ++i)
            assertEquals(ints[i], q.poll());
    }

    /**
     * isEmpty is true before add, false after
     */
    public void testEmpty() {
        LinkedList q = new LinkedList();
        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() {
        LinkedList 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) succeeds
     */
    public void testOfferNull() {
        LinkedList q = new LinkedList();
        q.offer(null);
        assertNull(q.get(0));
        assertTrue(q.contains(null));
    }

    /**
     * Offer succeeds
     */
    public void testOffer() {
        LinkedList q = new LinkedList();
        assertTrue(q.offer(new Integer(0)));
        assertTrue(q.offer(new Integer(1)));
    }

    /**
     * add succeeds
     */
    public void testAdd() {
        LinkedList q = new LinkedList();
        for (int i = 0; i < SIZE; ++i) {
            assertEquals(i, q.size());
            assertTrue(q.add(new Integer(i)));
        }
    }

    /**
     * addAll(null) throws NPE
     */
    public void testAddAll1() {
        LinkedList q = new LinkedList();
        try {
            q.addAll(null);
            shouldThrow();
        } catch (NullPointerException success) {}
    }

    /**
     * Queue contains all elements, in traversal order, of successful addAll
     */
    public void testAddAll5() {
        Integer[] empty = new Integer[0];
        Integer[] ints = new Integer[SIZE];
        for (int i = 0; i < SIZE; ++i)
            ints[i] = i;
        LinkedList q = new LinkedList();
        assertFalse(q.addAll(Arrays.asList(empty)));
        assertTrue(q.addAll(Arrays.asList(ints)));
        for (int i = 0; i < SIZE; ++i)
            assertEquals(ints[i], q.poll());
    }

    /**
     * addAll with too large an index throws IOOBE
     */
    public void testAddAll2_IndexOutOfBoundsException() {
        LinkedList l = new LinkedList();
        l.add(new Object());
        LinkedList m = new LinkedList();
        m.add(new Object());
        try {
            l.addAll(4,m);
            shouldThrow();
        } catch (IndexOutOfBoundsException success) {}
    }

    /**
     * addAll with negative index throws IOOBE
     */
    public void testAddAll4_BadIndex() {
        LinkedList l = new LinkedList();
        l.add(new Object());
        LinkedList m = new LinkedList();
        m.add(new Object());
        try {
            l.addAll(-1,m);
            shouldThrow();
        } catch (IndexOutOfBoundsException success) {}
    }

    /**
     * poll succeeds unless empty
     */
    public void testPoll() {
        LinkedList q = populatedQueue(SIZE);
        for (int i = 0; i < SIZE; ++i) {
            assertEquals(i, q.poll());
        }
        assertNull(q.poll());
    }

    /**
     * peek returns next element, or null if empty
     */
    public void testPeek() {
        LinkedList q = populatedQueue(SIZE);
        for (int i = 0; i < SIZE; ++i) {
            assertEquals(i, q.peek());
            assertEquals(i, q.poll());
            assertTrue(q.peek() == null ||
                       !q.peek().equals(i));
        }
        assertNull(q.peek());
    }

    /**
     * element returns next element, or throws NSEE if empty
     */
    public void testElement() {
        LinkedList q = populatedQueue(SIZE);
        for (int i = 0; i < SIZE; ++i) {
            assertEquals(i, q.element());
            assertEquals(i, q.poll());
        }
        try {
            q.element();
            shouldThrow();
        } catch (NoSuchElementException success) {}
    }

    /**
     * remove removes next element, or throws NSEE if empty
     */
    public void testRemove() {
        LinkedList q = populatedQueue(SIZE);
        for (int i = 0; i < SIZE; ++i) {
            assertEquals(i, q.remove());
        }
        try {
            q.remove();
            shouldThrow();
        } catch (NoSuchElementException success) {}
    }

    /**
     * remove(x) removes x and returns true if present
     */
    public void testRemoveElement() {
        LinkedList q = populatedQueue(SIZE);
        for (int i = 1; i < SIZE; i += 2) {
            assertTrue(q.contains(i));
            assertTrue(q.remove((Integer)i));
            assertFalse(q.contains(i));
            assertTrue(q.contains(i - 1));
        }
        for (int i = 0; i < SIZE; i += 2) {
            assertTrue(q.contains(i));
            assertTrue(q.remove((Integer)i));
            assertFalse(q.contains(i));
            assertFalse(q.remove((Integer)(i + 1)));
            assertFalse(q.contains(i + 1));
        }
        assertTrue(q.isEmpty());
    }

    /**
     * contains(x) reports true when elements added but not yet removed
     */
    public void testContains() {
        LinkedList 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() {
        LinkedList q = populatedQueue(SIZE);
        q.clear();
        assertTrue(q.isEmpty());
        assertEquals(0, q.size());
        assertTrue(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() {
        LinkedList q = populatedQueue(SIZE);
        LinkedList p = new LinkedList();
        for (int i = 0; i < SIZE; ++i) {
            assertTrue(q.containsAll(p));
            assertFalse(p.containsAll(q));
            assertTrue(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() {
        LinkedList q = populatedQueue(SIZE);
        LinkedList 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) {
            LinkedList q = populatedQueue(SIZE);
            LinkedList p = populatedQueue(i);
            assertTrue(q.removeAll(p));
            assertEquals(SIZE - i, q.size());
            for (int j = 0; j < i; ++j) {
                Integer x = (Integer)(p.remove());
                assertFalse(q.contains(x));
            }
        }
    }

    /**
     * toArray contains all elements in FIFO order
     */
    public void testToArray() {
        LinkedList q = populatedQueue(SIZE);
        Object[] o = q.toArray();
        for (int i = 0; i < o.length; i++)
            assertSame(o[i], q.poll());
    }

    /**
     * toArray(a) contains all elements in FIFO order
     */
    public void testToArray2() {
        LinkedList<Integer> q = populatedQueue(SIZE);
        Integer[] ints = new Integer[SIZE];
        Integer[] array = q.toArray(ints);
        assertSame(ints, array);
        for (int i = 0; i < ints.length; i++)
            assertSame(ints[i], q.poll());
    }

    /**
     * toArray(null) throws NullPointerException
     */
    public void testToArray_NullArg() {
        LinkedList l = new LinkedList();
        l.add(new Object());
        try {
            l.toArray(null);
            shouldThrow();
        } catch (NullPointerException success) {}
    }

    /**
     * toArray(incompatible array type) throws ArrayStoreException
     */
    public void testToArray1_BadArg() {
        LinkedList l = new LinkedList();
        l.add(new Integer(5));
        try {
            l.toArray(new String[10]);
            shouldThrow();
        } catch (ArrayStoreException success) {}
    }

    /**
     * iterator iterates through all elements
     */
    public void testIterator() {
        LinkedList q = populatedQueue(SIZE);
        Iterator it = q.iterator();
        int i;
        for (i = 0; it.hasNext(); i++)
            assertTrue(q.contains(it.next()));
        assertEquals(i, SIZE);
        assertIteratorExhausted(it);
    }

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

    /**
     * iterator ordering is FIFO
     */
    public void testIteratorOrdering() {
        final LinkedList q = new LinkedList();
        q.add(new Integer(1));
        q.add(new Integer(2));
        q.add(new Integer(3));
        int k = 0;
        for (Iterator it = q.iterator(); it.hasNext();) {
            assertEquals(++k, it.next());
        }

        assertEquals(3, k);
    }

    /**
     * iterator.remove removes current element
     */
    public void testIteratorRemove() {
        final LinkedList q = new LinkedList();
        q.add(new Integer(1));
        q.add(new Integer(2));
        q.add(new Integer(3));
        Iterator it = q.iterator();
        assertEquals(1, it.next());
        it.remove();
        it = q.iterator();
        assertEquals(2, it.next());
        assertEquals(3, it.next());
        assertFalse(it.hasNext());
    }

    /**
     * Descending iterator iterates through all elements
     */
    public void testDescendingIterator() {
        LinkedList q = populatedQueue(SIZE);
        int i = 0;
        Iterator it = q.descendingIterator();
        while (it.hasNext()) {
            assertTrue(q.contains(it.next()));
            ++i;
        }
        assertEquals(i, SIZE);
        assertFalse(it.hasNext());
        try {
            it.next();
            shouldThrow();
        } catch (NoSuchElementException success) {}
    }

    /**
     * Descending iterator ordering is reverse FIFO
     */
    public void testDescendingIteratorOrdering() {
        final LinkedList q = new LinkedList();
        q.add(new Integer(3));
        q.add(new Integer(2));
        q.add(new Integer(1));
        int k = 0;
        for (Iterator it = q.descendingIterator(); it.hasNext();) {
            assertEquals(++k, it.next());
        }

        assertEquals(3, k);
    }

    /**
     * descendingIterator.remove removes current element
     */
    public void testDescendingIteratorRemove() {
        final LinkedList q = new LinkedList();
        q.add(three);
        q.add(two);
        q.add(one);
        Iterator it = q.descendingIterator();
        it.next();
        it.remove();
        it = q.descendingIterator();
        assertSame(it.next(), two);
        assertSame(it.next(), three);
        assertFalse(it.hasNext());
    }

    /**
     * toString contains toStrings of elements
     */
    public void testToString() {
        LinkedList q = populatedQueue(SIZE);
        String s = q.toString();
        for (int i = 0; i < SIZE; ++i) {
            assertTrue(s.contains(String.valueOf(i)));
        }
    }

    /**
     * peek returns element inserted with addFirst
     */
    public void testAddFirst() {
        LinkedList q = populatedQueue(3);
        q.addFirst(four);
        assertSame(four, q.peek());
    }

    /**
     * peekFirst returns element inserted with push
     */
    public void testPush() {
        LinkedList q = populatedQueue(3);
        q.push(four);
        assertSame(four, q.peekFirst());
    }

    /**
     * pop removes next element, or throws NSEE if empty
     */
    public void testPop() {
        LinkedList q = populatedQueue(SIZE);
        for (int i = 0; i < SIZE; ++i) {
            assertEquals(i, q.pop());
        }
        try {
            q.pop();
            shouldThrow();
        } catch (NoSuchElementException success) {}
    }

    /**
     * OfferFirst succeeds
     */
    public void testOfferFirst() {
        LinkedList q = new LinkedList();
        assertTrue(q.offerFirst(new Integer(0)));
        assertTrue(q.offerFirst(new Integer(1)));
    }

    /**
     * OfferLast succeeds
     */
    public void testOfferLast() {
        LinkedList q = new LinkedList();
        assertTrue(q.offerLast(new Integer(0)));
        assertTrue(q.offerLast(new Integer(1)));
    }

    /**
     * pollLast succeeds unless empty
     */
    public void testPollLast() {
        LinkedList q = populatedQueue(SIZE);
        for (int i = SIZE - 1; i >= 0; --i) {
            assertEquals(i, q.pollLast());
        }
        assertNull(q.pollLast());
    }

    /**
     * peekFirst returns next element, or null if empty
     */
    public void testPeekFirst() {
        LinkedList q = populatedQueue(SIZE);
        for (int i = 0; i < SIZE; ++i) {
            assertEquals(i, q.peekFirst());
            assertEquals(i, q.pollFirst());
            assertTrue(q.peekFirst() == null ||
                       !q.peekFirst().equals(i));
        }
        assertNull(q.peekFirst());
    }

    /**
     * peekLast returns next element, or null if empty
     */
    public void testPeekLast() {
        LinkedList q = populatedQueue(SIZE);
        for (int i = SIZE - 1; i >= 0; --i) {
            assertEquals(i, q.peekLast());
            assertEquals(i, q.pollLast());
            assertTrue(q.peekLast() == null ||
                       !q.peekLast().equals(i));
        }
        assertNull(q.peekLast());
    }

    public void testFirstElement() {
        LinkedList q = populatedQueue(SIZE);
        for (int i = 0; i < SIZE; ++i) {
            assertEquals(i, q.getFirst());
            assertEquals(i, q.pollFirst());
        }
        try {
            q.getFirst();
            shouldThrow();
        } catch (NoSuchElementException success) {}
    }

    /**
     * getLast returns next element, or throws NSEE if empty
     */
    public void testLastElement() {
        LinkedList q = populatedQueue(SIZE);
        for (int i = SIZE - 1; i >= 0; --i) {
            assertEquals(i, q.getLast());
            assertEquals(i, q.pollLast());
        }
        try {
            q.getLast();
            shouldThrow();
        } catch (NoSuchElementException success) {}
        assertNull(q.peekLast());
    }

    /**
     * removeFirstOccurrence(x) removes x and returns true if present
     */
    public void testRemoveFirstOccurrence() {
        LinkedList q = populatedQueue(SIZE);
        for (int i = 1; i < SIZE; i += 2) {
            assertTrue(q.removeFirstOccurrence(new Integer(i)));
        }
        for (int i = 0; i < SIZE; i += 2) {
            assertTrue(q.removeFirstOccurrence(new Integer(i)));
            assertFalse(q.removeFirstOccurrence(new Integer(i + 1)));
        }
        assertTrue(q.isEmpty());
    }

    /**
     * removeLastOccurrence(x) removes x and returns true if present
     */
    public void testRemoveLastOccurrence() {
        LinkedList q = populatedQueue(SIZE);
        for (int i = 1; i < SIZE; i += 2) {
            assertTrue(q.removeLastOccurrence(new Integer(i)));
        }
        for (int i = 0; i < SIZE; i += 2) {
            assertTrue(q.removeLastOccurrence(new Integer(i)));
            assertFalse(q.removeLastOccurrence(new Integer(i + 1)));
        }
        assertTrue(q.isEmpty());
    }

}
Revision:	1.40
Committed:	Sun May 24 01:42:14 2015 UTC (8 years, 11 months ago) by jsr166
Branch:	MAIN
Changes since 1.39:	+5 -5 lines
Log Message:	whitespace
#	User	Rev	Content
1	dl	1.1	/*
2	dl	1.7	* 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	1.26	* http://creativecommons.org/publicdomain/zero/1.0/
5	jsr166	1.10	* Other contributors include Andrew Wright, Jeffrey Hayes,
6			* Pat Fisher, Mike Judd.
7	dl	1.1	*/
8
9	jsr166	1.28	import java.util.Arrays;
10			import java.util.Collection;
11			import java.util.Iterator;
12			import java.util.LinkedList;
13			import java.util.NoSuchElementException;
14	dl	1.1
15	jsr166	1.32	import junit.framework.Test;
16			import junit.framework.TestSuite;
17
18	dl	1.3	public class LinkedListTest extends JSR166TestCase {
19	dl	1.1	public static void main(String[] args) {
20	jsr166	1.37	main(suite(), args);
21	dl	1.1	}
22
23			public static Test suite() {
24	jsr166	1.13	return new TestSuite(LinkedListTest.class);
25	dl	1.1	}
26
27			/**
28	jsr166	1.31	* Returns a new queue of given size containing consecutive
29	dl	1.1	* Integers 0 ... n.
30			*/
31	jsr166	1.24	private LinkedList<Integer> populatedQueue(int n) {
32			LinkedList<Integer> q = new LinkedList<Integer>();
33	dl	1.1	assertTrue(q.isEmpty());
34	jsr166	1.13	for (int i = 0; i < n; ++i)
35			assertTrue(q.offer(new Integer(i)));
36	dl	1.1	assertFalse(q.isEmpty());
37	jsr166	1.13	assertEquals(n, q.size());
38	dl	1.1	return q;
39			}
40	jsr166	1.10
41	dl	1.4	/**
42	dl	1.5	* new queue is empty
43	dl	1.4	*/
44			public void testConstructor1() {
45	dl	1.1	assertEquals(0, new LinkedList().size());
46			}
47
48	dl	1.4	/**
49	dl	1.5	* Initializing from null Collection throws NPE
50	dl	1.4	*/
51	dl	1.1	public void testConstructor3() {
52			try {
53	jsr166	1.36	new LinkedList((Collection)null);
54	dl	1.4	shouldThrow();
55	jsr166	1.14	} catch (NullPointerException success) {}
56	dl	1.1	}
57
58	dl	1.4	/**
59	dl	1.5	* Queue contains all elements of collection used to initialize
60	dl	1.4	*/
61			public void testConstructor6() {
62	jsr166	1.14	Integer[] ints = new Integer[SIZE];
63			for (int i = 0; i < SIZE; ++i)
64	jsr166	1.16	ints[i] = i;
65	jsr166	1.14	LinkedList q = new LinkedList(Arrays.asList(ints));
66			for (int i = 0; i < SIZE; ++i)
67			assertEquals(ints[i], q.poll());
68	dl	1.1	}
69
70	dl	1.4	/**
71	dl	1.5	* isEmpty is true before add, false after
72	dl	1.4	*/
73	dl	1.1	public void testEmpty() {
74			LinkedList q = new LinkedList();
75			assertTrue(q.isEmpty());
76			q.add(new Integer(1));
77			assertFalse(q.isEmpty());
78			q.add(new Integer(2));
79			q.remove();
80			q.remove();
81			assertTrue(q.isEmpty());
82			}
83
84	dl	1.4	/**
85	dl	1.5	* size changes when elements added and removed
86	dl	1.4	*/
87	dl	1.1	public void testSize() {
88	dl	1.3	LinkedList q = populatedQueue(SIZE);
89			for (int i = 0; i < SIZE; ++i) {
90	jsr166	1.39	assertEquals(SIZE - i, q.size());
91	dl	1.1	q.remove();
92			}
93	dl	1.3	for (int i = 0; i < SIZE; ++i) {
94	dl	1.1	assertEquals(i, q.size());
95			q.add(new Integer(i));
96			}
97			}
98
99	dl	1.4	/**
100	dl	1.5	* offer(null) succeeds
101	dl	1.4	*/
102			public void testOfferNull() {
103	jsr166	1.14	LinkedList q = new LinkedList();
104			q.offer(null);
105	jsr166	1.38	assertNull(q.get(0));
106			assertTrue(q.contains(null));
107	dl	1.1	}
108
109	dl	1.4	/**
110	jsr166	1.10	* Offer succeeds
111	dl	1.4	*/
112	dl	1.1	public void testOffer() {
113			LinkedList q = new LinkedList();
114			assertTrue(q.offer(new Integer(0)));
115			assertTrue(q.offer(new Integer(1)));
116			}
117
118	dl	1.4	/**
119	dl	1.5	* add succeeds
120	dl	1.4	*/
121			public void testAdd() {
122	dl	1.1	LinkedList q = new LinkedList();
123	dl	1.3	for (int i = 0; i < SIZE; ++i) {
124	dl	1.1	assertEquals(i, q.size());
125			assertTrue(q.add(new Integer(i)));
126			}
127			}
128
129	dl	1.4	/**
130	dl	1.5	* addAll(null) throws NPE
131	dl	1.4	*/
132			public void testAddAll1() {
133	jsr166	1.38	LinkedList q = new LinkedList();
134	dl	1.1	try {
135			q.addAll(null);
136	dl	1.4	shouldThrow();
137	jsr166	1.14	} catch (NullPointerException success) {}
138	dl	1.1	}
139
140	dl	1.4	/**
141	dl	1.5	* Queue contains all elements, in traversal order, of successful addAll
142	dl	1.4	*/
143			public void testAddAll5() {
144	jsr166	1.14	Integer[] empty = new Integer[0];
145			Integer[] ints = new Integer[SIZE];
146			for (int i = 0; i < SIZE; ++i)
147	jsr166	1.16	ints[i] = i;
148	jsr166	1.14	LinkedList q = new LinkedList();
149			assertFalse(q.addAll(Arrays.asList(empty)));
150			assertTrue(q.addAll(Arrays.asList(ints)));
151			for (int i = 0; i < SIZE; ++i)
152			assertEquals(ints[i], q.poll());
153	dl	1.1	}
154
155	dl	1.4	/**
156	dl	1.5	* addAll with too large an index throws IOOBE
157			*/
158			public void testAddAll2_IndexOutOfBoundsException() {
159	jsr166	1.14	LinkedList l = new LinkedList();
160			l.add(new Object());
161			LinkedList m = new LinkedList();
162			m.add(new Object());
163	jsr166	1.13	try {
164			l.addAll(4,m);
165			shouldThrow();
166	jsr166	1.15	} catch (IndexOutOfBoundsException success) {}
167	dl	1.5	}
168
169			/**
170			* addAll with negative index throws IOOBE
171			*/
172			public void testAddAll4_BadIndex() {
173	jsr166	1.14	LinkedList l = new LinkedList();
174			l.add(new Object());
175			LinkedList m = new LinkedList();
176			m.add(new Object());
177	jsr166	1.13	try {
178			l.addAll(-1,m);
179			shouldThrow();
180	jsr166	1.15	} catch (IndexOutOfBoundsException success) {}
181	dl	1.5	}
182
183			/**
184	jsr166	1.20	* poll succeeds unless empty
185	dl	1.4	*/
186			public void testPoll() {
187	dl	1.3	LinkedList q = populatedQueue(SIZE);
188			for (int i = 0; i < SIZE; ++i) {
189	jsr166	1.16	assertEquals(i, q.poll());
190	dl	1.1	}
191	jsr166	1.13	assertNull(q.poll());
192	dl	1.1	}
193
194	dl	1.4	/**
195	jsr166	1.20	* peek returns next element, or null if empty
196	dl	1.4	*/
197			public void testPeek() {
198	dl	1.3	LinkedList q = populatedQueue(SIZE);
199			for (int i = 0; i < SIZE; ++i) {
200	jsr166	1.16	assertEquals(i, q.peek());
201			assertEquals(i, q.poll());
202	dl	1.1	assertTrue(q.peek() == null \|\|
203	jsr166	1.16	!q.peek().equals(i));
204	dl	1.1	}
205	jsr166	1.13	assertNull(q.peek());
206	dl	1.1	}
207
208	dl	1.4	/**
209	dl	1.6	* element returns next element, or throws NSEE if empty
210	dl	1.4	*/
211			public void testElement() {
212	dl	1.3	LinkedList q = populatedQueue(SIZE);
213			for (int i = 0; i < SIZE; ++i) {
214	jsr166	1.16	assertEquals(i, q.element());
215			assertEquals(i, q.poll());
216	dl	1.1	}
217			try {
218			q.element();
219	dl	1.4	shouldThrow();
220	jsr166	1.14	} catch (NoSuchElementException success) {}
221	dl	1.1	}
222
223	dl	1.4	/**
224	jsr166	1.20	* remove removes next element, or throws NSEE if empty
225	dl	1.4	*/
226			public void testRemove() {
227	dl	1.3	LinkedList q = populatedQueue(SIZE);
228			for (int i = 0; i < SIZE; ++i) {
229	jsr166	1.16	assertEquals(i, q.remove());
230	dl	1.1	}
231			try {
232			q.remove();
233	dl	1.4	shouldThrow();
234	jsr166	1.14	} catch (NoSuchElementException success) {}
235	dl	1.1	}
236
237	dl	1.4	/**
238	dl	1.5	* remove(x) removes x and returns true if present
239	dl	1.4	*/
240			public void testRemoveElement() {
241	dl	1.3	LinkedList q = populatedQueue(SIZE);
242	jsr166	1.33	for (int i = 1; i < SIZE; i += 2) {
243	jsr166	1.25	assertTrue(q.contains(i));
244			assertTrue(q.remove((Integer)i));
245			assertFalse(q.contains(i));
246	jsr166	1.40	assertTrue(q.contains(i - 1));
247	dl	1.1	}
248	jsr166	1.33	for (int i = 0; i < SIZE; i += 2) {
249	jsr166	1.25	assertTrue(q.contains(i));
250			assertTrue(q.remove((Integer)i));
251			assertFalse(q.contains(i));
252	jsr166	1.40	assertFalse(q.remove((Integer)(i + 1)));
253			assertFalse(q.contains(i + 1));
254	dl	1.1	}
255	dl	1.2	assertTrue(q.isEmpty());
256	dl	1.1	}
257	jsr166	1.10
258	dl	1.4	/**
259	dl	1.5	* contains(x) reports true when elements added but not yet removed
260	dl	1.4	*/
261			public void testContains() {
262	dl	1.3	LinkedList q = populatedQueue(SIZE);
263			for (int i = 0; i < SIZE; ++i) {
264	dl	1.1	assertTrue(q.contains(new Integer(i)));
265			q.poll();
266			assertFalse(q.contains(new Integer(i)));
267			}
268			}
269
270	dl	1.4	/**
271	dl	1.5	* clear removes all elements
272	dl	1.4	*/
273			public void testClear() {
274	dl	1.3	LinkedList q = populatedQueue(SIZE);
275	dl	1.1	q.clear();
276			assertTrue(q.isEmpty());
277			assertEquals(0, q.size());
278	jsr166	1.16	assertTrue(q.add(new Integer(1)));
279	dl	1.1	assertFalse(q.isEmpty());
280			q.clear();
281			assertTrue(q.isEmpty());
282			}
283
284	dl	1.4	/**
285	dl	1.5	* containsAll(c) is true when c contains a subset of elements
286	dl	1.4	*/
287			public void testContainsAll() {
288	dl	1.3	LinkedList q = populatedQueue(SIZE);
289	dl	1.1	LinkedList p = new LinkedList();
290	dl	1.3	for (int i = 0; i < SIZE; ++i) {
291	dl	1.1	assertTrue(q.containsAll(p));
292			assertFalse(p.containsAll(q));
293	jsr166	1.16	assertTrue(p.add(new Integer(i)));
294	dl	1.1	}
295			assertTrue(p.containsAll(q));
296			}
297
298	dl	1.4	/**
299	dl	1.5	* retainAll(c) retains only those elements of c and reports true if changed
300	dl	1.4	*/
301			public void testRetainAll() {
302	dl	1.3	LinkedList q = populatedQueue(SIZE);
303			LinkedList p = populatedQueue(SIZE);
304			for (int i = 0; i < SIZE; ++i) {
305	dl	1.1	boolean changed = q.retainAll(p);
306			if (i == 0)
307			assertFalse(changed);
308			else
309			assertTrue(changed);
310
311			assertTrue(q.containsAll(p));
312	jsr166	1.39	assertEquals(SIZE - i, q.size());
313	dl	1.1	p.remove();
314			}
315			}
316
317	dl	1.4	/**
318	dl	1.6	* removeAll(c) removes only those elements of c and reports true if changed
319	dl	1.4	*/
320			public void testRemoveAll() {
321	dl	1.3	for (int i = 1; i < SIZE; ++i) {
322			LinkedList q = populatedQueue(SIZE);
323			LinkedList p = populatedQueue(i);
324	dl	1.1	assertTrue(q.removeAll(p));
325	jsr166	1.39	assertEquals(SIZE - i, q.size());
326	dl	1.1	for (int j = 0; j < i; ++j) {
327	jsr166	1.34	Integer x = (Integer)(p.remove());
328			assertFalse(q.contains(x));
329	dl	1.1	}
330			}
331			}
332
333	dl	1.4	/**
334	jsr166	1.23	* toArray contains all elements in FIFO order
335	dl	1.4	*/
336			public void testToArray() {
337	dl	1.3	LinkedList q = populatedQueue(SIZE);
338	jsr166	1.13	Object[] o = q.toArray();
339			for (int i = 0; i < o.length; i++)
340	jsr166	1.23	assertSame(o[i], q.poll());
341	dl	1.1	}
342
343	dl	1.4	/**
344	jsr166	1.23	* toArray(a) contains all elements in FIFO order
345	dl	1.4	*/
346			public void testToArray2() {
347	jsr166	1.24	LinkedList<Integer> q = populatedQueue(SIZE);
348	jsr166	1.13	Integer[] ints = new Integer[SIZE];
349	jsr166	1.24	Integer[] array = q.toArray(ints);
350			assertSame(ints, array);
351	jsr166	1.11	for (int i = 0; i < ints.length; i++)
352	jsr166	1.23	assertSame(ints[i], q.poll());
353	dl	1.1	}
354	dl	1.5
355			/**
356	jsr166	1.22	* toArray(null) throws NullPointerException
357	dl	1.5	*/
358	jsr166	1.22	public void testToArray_NullArg() {
359	jsr166	1.16	LinkedList l = new LinkedList();
360			l.add(new Object());
361	jsr166	1.13	try {
362	jsr166	1.22	l.toArray(null);
363	jsr166	1.13	shouldThrow();
364			} catch (NullPointerException success) {}
365	dl	1.5	}
366
367			/**
368	jsr166	1.21	* toArray(incompatible array type) throws ArrayStoreException
369	dl	1.5	*/
370			public void testToArray1_BadArg() {
371	jsr166	1.16	LinkedList l = new LinkedList();
372			l.add(new Integer(5));
373	jsr166	1.13	try {
374	jsr166	1.21	l.toArray(new String[10]);
375	jsr166	1.13	shouldThrow();
376	jsr166	1.14	} catch (ArrayStoreException success) {}
377	dl	1.5	}
378	jsr166	1.10
379	dl	1.4	/**
380	jsr166	1.20	* iterator iterates through all elements
381	dl	1.4	*/
382			public void testIterator() {
383	dl	1.3	LinkedList q = populatedQueue(SIZE);
384	jsr166	1.13	Iterator it = q.iterator();
385	jsr166	1.35	int i;
386			for (i = 0; it.hasNext(); i++)
387	dl	1.1	assertTrue(q.contains(it.next()));
388	dl	1.3	assertEquals(i, SIZE);
389	jsr166	1.35	assertIteratorExhausted(it);
390			}
391
392			/**
393			* iterator of empty collection has no elements
394			*/
395			public void testEmptyIterator() {
396			assertIteratorExhausted(new LinkedList().iterator());
397	dl	1.1	}
398
399	dl	1.4	/**
400	jsr166	1.20	* iterator ordering is FIFO
401	dl	1.4	*/
402	dl	1.1	public void testIteratorOrdering() {
403			final LinkedList q = new LinkedList();
404			q.add(new Integer(1));
405			q.add(new Integer(2));
406			q.add(new Integer(3));
407			int k = 0;
408			for (Iterator it = q.iterator(); it.hasNext();) {
409	jsr166	1.16	assertEquals(++k, it.next());
410	dl	1.1	}
411
412	dl	1.4	assertEquals(3, k);
413	dl	1.1	}
414
415	dl	1.4	/**
416	dl	1.5	* iterator.remove removes current element
417	dl	1.4	*/
418	jsr166	1.19	public void testIteratorRemove() {
419	dl	1.1	final LinkedList q = new LinkedList();
420			q.add(new Integer(1));
421			q.add(new Integer(2));
422			q.add(new Integer(3));
423			Iterator it = q.iterator();
424	jsr166	1.29	assertEquals(1, it.next());
425	dl	1.1	it.remove();
426			it = q.iterator();
427	jsr166	1.29	assertEquals(2, it.next());
428			assertEquals(3, it.next());
429	dl	1.1	assertFalse(it.hasNext());
430			}
431
432	dl	1.9	/**
433	jsr166	1.20	* Descending iterator iterates through all elements
434	dl	1.9	*/
435			public void testDescendingIterator() {
436			LinkedList q = populatedQueue(SIZE);
437			int i = 0;
438	jsr166	1.13	Iterator it = q.descendingIterator();
439	jsr166	1.11	while (it.hasNext()) {
440	dl	1.9	assertTrue(q.contains(it.next()));
441			++i;
442			}
443			assertEquals(i, SIZE);
444			assertFalse(it.hasNext());
445			try {
446			it.next();
447	jsr166	1.14	shouldThrow();
448			} catch (NoSuchElementException success) {}
449	dl	1.9	}
450
451			/**
452	jsr166	1.20	* Descending iterator ordering is reverse FIFO
453	dl	1.9	*/
454			public void testDescendingIteratorOrdering() {
455			final LinkedList q = new LinkedList();
456			q.add(new Integer(3));
457			q.add(new Integer(2));
458			q.add(new Integer(1));
459			int k = 0;
460			for (Iterator it = q.descendingIterator(); it.hasNext();) {
461	jsr166	1.16	assertEquals(++k, it.next());
462	dl	1.9	}
463
464			assertEquals(3, k);
465			}
466
467			/**
468			* descendingIterator.remove removes current element
469			*/
470	jsr166	1.19	public void testDescendingIteratorRemove() {
471	dl	1.9	final LinkedList q = new LinkedList();
472	jsr166	1.17	q.add(three);
473			q.add(two);
474			q.add(one);
475	dl	1.9	Iterator it = q.descendingIterator();
476			it.next();
477			it.remove();
478			it = q.descendingIterator();
479	jsr166	1.17	assertSame(it.next(), two);
480			assertSame(it.next(), three);
481	dl	1.9	assertFalse(it.hasNext());
482			}
483
484	dl	1.4	/**
485	dl	1.5	* toString contains toStrings of elements
486	dl	1.4	*/
487			public void testToString() {
488	dl	1.3	LinkedList q = populatedQueue(SIZE);
489	dl	1.1	String s = q.toString();
490	dl	1.3	for (int i = 0; i < SIZE; ++i) {
491	jsr166	1.27	assertTrue(s.contains(String.valueOf(i)));
492	dl	1.1	}
493	jsr166	1.10	}
494	dl	1.1
495	dl	1.4	/**
496	dl	1.5	* peek returns element inserted with addFirst
497	dl	1.4	*/
498			public void testAddFirst() {
499	dl	1.3	LinkedList q = populatedQueue(3);
500	jsr166	1.13	q.addFirst(four);
501	jsr166	1.17	assertSame(four, q.peek());
502	jsr166	1.10	}
503	dl	1.1
504	dl	1.8	/**
505			* peekFirst returns element inserted with push
506			*/
507			public void testPush() {
508			LinkedList q = populatedQueue(3);
509	jsr166	1.13	q.push(four);
510	jsr166	1.17	assertSame(four, q.peekFirst());
511	jsr166	1.10	}
512	dl	1.8
513			/**
514	jsr166	1.20	* pop removes next element, or throws NSEE if empty
515	dl	1.8	*/
516			public void testPop() {
517			LinkedList q = populatedQueue(SIZE);
518			for (int i = 0; i < SIZE; ++i) {
519	jsr166	1.16	assertEquals(i, q.pop());
520	dl	1.8	}
521			try {
522			q.pop();
523			shouldThrow();
524	jsr166	1.14	} catch (NoSuchElementException success) {}
525	dl	1.8	}
526
527			/**
528	jsr166	1.10	* OfferFirst succeeds
529	dl	1.8	*/
530			public void testOfferFirst() {
531			LinkedList q = new LinkedList();
532			assertTrue(q.offerFirst(new Integer(0)));
533			assertTrue(q.offerFirst(new Integer(1)));
534			}
535
536			/**
537	jsr166	1.10	* OfferLast succeeds
538	dl	1.8	*/
539			public void testOfferLast() {
540			LinkedList q = new LinkedList();
541			assertTrue(q.offerLast(new Integer(0)));
542			assertTrue(q.offerLast(new Integer(1)));
543			}
544
545			/**
546	jsr166	1.20	* pollLast succeeds unless empty
547	dl	1.8	*/
548			public void testPollLast() {
549			LinkedList q = populatedQueue(SIZE);
550	jsr166	1.39	for (int i = SIZE - 1; i >= 0; --i) {
551	jsr166	1.16	assertEquals(i, q.pollLast());
552	dl	1.8	}
553	jsr166	1.13	assertNull(q.pollLast());
554	dl	1.8	}
555
556			/**
557	jsr166	1.20	* peekFirst returns next element, or null if empty
558	dl	1.8	*/
559			public void testPeekFirst() {
560			LinkedList q = populatedQueue(SIZE);
561			for (int i = 0; i < SIZE; ++i) {
562	jsr166	1.16	assertEquals(i, q.peekFirst());
563			assertEquals(i, q.pollFirst());
564	dl	1.8	assertTrue(q.peekFirst() == null \|\|
565	jsr166	1.16	!q.peekFirst().equals(i));
566	dl	1.8	}
567	jsr166	1.13	assertNull(q.peekFirst());
568	dl	1.8	}
569
570			/**
571	jsr166	1.20	* peekLast returns next element, or null if empty
572	dl	1.8	*/
573			public void testPeekLast() {
574			LinkedList q = populatedQueue(SIZE);
575	jsr166	1.39	for (int i = SIZE - 1; i >= 0; --i) {
576	jsr166	1.16	assertEquals(i, q.peekLast());
577			assertEquals(i, q.pollLast());
578	dl	1.8	assertTrue(q.peekLast() == null \|\|
579	jsr166	1.16	!q.peekLast().equals(i));
580	dl	1.8	}
581	jsr166	1.13	assertNull(q.peekLast());
582	dl	1.8	}
583
584			public void testFirstElement() {
585			LinkedList q = populatedQueue(SIZE);
586			for (int i = 0; i < SIZE; ++i) {
587	jsr166	1.16	assertEquals(i, q.getFirst());
588			assertEquals(i, q.pollFirst());
589	dl	1.8	}
590			try {
591			q.getFirst();
592			shouldThrow();
593	jsr166	1.14	} catch (NoSuchElementException success) {}
594	dl	1.8	}
595
596			/**
597	jsr166	1.20	* getLast returns next element, or throws NSEE if empty
598	dl	1.8	*/
599			public void testLastElement() {
600			LinkedList q = populatedQueue(SIZE);
601	jsr166	1.39	for (int i = SIZE - 1; i >= 0; --i) {
602	jsr166	1.16	assertEquals(i, q.getLast());
603			assertEquals(i, q.pollLast());
604	dl	1.8	}
605			try {
606			q.getLast();
607			shouldThrow();
608	jsr166	1.14	} catch (NoSuchElementException success) {}
609	jsr166	1.13	assertNull(q.peekLast());
610	dl	1.8	}
611
612			/**
613			* removeFirstOccurrence(x) removes x and returns true if present
614			*/
615			public void testRemoveFirstOccurrence() {
616			LinkedList q = populatedQueue(SIZE);
617	jsr166	1.33	for (int i = 1; i < SIZE; i += 2) {
618	dl	1.8	assertTrue(q.removeFirstOccurrence(new Integer(i)));
619			}
620	jsr166	1.33	for (int i = 0; i < SIZE; i += 2) {
621	dl	1.8	assertTrue(q.removeFirstOccurrence(new Integer(i)));
622	jsr166	1.40	assertFalse(q.removeFirstOccurrence(new Integer(i + 1)));
623	dl	1.8	}
624			assertTrue(q.isEmpty());
625			}
626
627			/**
628			* removeLastOccurrence(x) removes x and returns true if present
629			*/
630			public void testRemoveLastOccurrence() {
631			LinkedList q = populatedQueue(SIZE);
632	jsr166	1.33	for (int i = 1; i < SIZE; i += 2) {
633	dl	1.8	assertTrue(q.removeLastOccurrence(new Integer(i)));
634			}
635	jsr166	1.33	for (int i = 0; i < SIZE; i += 2) {
636	dl	1.8	assertTrue(q.removeLastOccurrence(new Integer(i)));
637	jsr166	1.40	assertFalse(q.removeLastOccurrence(new Integer(i + 1)));
638	dl	1.8	}
639			assertTrue(q.isEmpty());
640			}
641
642	dl	1.1	}