ChorusLine.java revision 12745:f068a4ffddd2 
1/*
2 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23
24/*
25 * @test
26 * @bug 6324846
27 * @summary Deque implementations must behave isomorphically
28 * @author Martin Buchholz
29 */
30
31import java.util.*;
32import java.util.concurrent.*;
33
34public class ChorusLine {
35    private interface Tweaker {
36        void run(Deque<Integer> deq);
37    }
38
39    private static final Tweaker[] tweakers = {
40        new Tweaker() { public void run(Deque<Integer> deq) {
41            for (int i = 0; i < 7; i++)
42                deq.addLast(i);
43            deq.removeFirst();
44            deq.removeFirst();
45            deq.addLast(7);
46            deq.addLast(8);
47            Iterator<Integer> it = deq.descendingIterator();
48            equal(it.next(), 8);
49            it.remove();
50
51            try {it.remove();}
52            catch (IllegalStateException e) {pass();}
53            catch (Throwable t) {unexpected(t);}
54
55            deq.addLast(9);
56            it = deq.descendingIterator();
57            equal(it.next(), 9);
58            equal(it.next(), 7);
59            it.remove();
60
61            try {it.remove();}
62            catch (IllegalStateException e) {pass();}
63            catch (Throwable t) {unexpected(t);}
64
65            equal(it.next(), 6);
66
67            System.out.println(deq);
68        }},
69        new Tweaker() { public void run(Deque<Integer> deq) {
70            deq.clear();
71            check(deq.isEmpty());
72            check(deq.size() == 0);
73            check(! deq.iterator().hasNext());
74            check(! deq.descendingIterator().hasNext());
75
76            try {deq.iterator().next(); fail();}
77            catch (NoSuchElementException e) {pass();}
78            catch (Throwable t) {unexpected(t);}
79
80            try {deq.descendingIterator().next(); fail();}
81            catch (NoSuchElementException e) {pass();}
82            catch (Throwable t) {unexpected(t);}
83        }},
84        new Tweaker() { public void run(Deque<Integer> deq) {
85            for (int i = 0; i < 11; i++)
86                deq.add(i);
87            Iterator<Integer> it = deq.iterator();
88            equal(it.next(), 0);
89            equal(it.next(), 1);
90            it.remove();
91            deq.addFirst(-1);
92            deq.addFirst(-2);
93            it = deq.iterator();
94            equal(it.next(), -2);
95            equal(it.next(), -1);
96            equal(it.next(), 0);
97            it.remove();
98
99            it = deq.descendingIterator();
100
101            try {it.remove(); fail();}
102            catch (IllegalStateException e) {pass();}
103            catch (Throwable t) {unexpected(t);}
104
105            equal(it.next(), 10);
106            it.remove();
107
108            try {it.remove(); fail();}
109            catch (IllegalStateException e) {pass();}
110            catch (Throwable t) {unexpected(t);}
111
112            equal(it.next(), 9);
113            equal(it.next(), 8);
114            it.remove();
115            System.out.println(deq);
116        }},
117        new Tweaker() { public void run(Deque<Integer> deq) {
118            while (deq.size() > 1) {
119                Iterator<Integer> it = deq.iterator();
120                it.next(); it.remove();
121                it = deq.descendingIterator();
122                it.next(); it.remove();
123            }
124            System.out.println(deq);
125        }}};
126
127    private static void realMain(String[] args) throws Throwable {
128        Collection<Deque<Integer>> deqs = new ArrayDeque<Deque<Integer>>(3);
129        deqs.add(new ArrayDeque<Integer>());
130        deqs.add(new LinkedList<Integer>());
131        deqs.add(new LinkedBlockingDeque<Integer>());
132        deqs.add(new ConcurrentLinkedDeque<Integer>());
133
134        equal(deqs);
135
136        for (Tweaker tweaker : tweakers) {
137            for (Deque<Integer> deq : deqs)
138                tweaker.run(deq);
139            equal(deqs);
140        }
141    }
142
143    private static void equal(Iterable<Deque<Integer>> deqs) {
144        Deque<Integer> prev = null;
145        for (Deque<Integer> deq : deqs) {
146            if (prev != null) {
147                equal(prev.isEmpty(), deq.isEmpty());
148                equal(prev.size(), deq.size());
149                equal(prev.toString(), deq.toString());
150            }
151            prev = deq;
152        }
153
154        Deque<Iterator<Integer>> its = new ArrayDeque<Iterator<Integer>>();
155        for (Deque<Integer> deq : deqs)
156            its.addLast(deq.iterator());
157        equal(its);
158
159        Deque<Iterator<Integer>> dits = new ArrayDeque<Iterator<Integer>>();
160        for (Deque<Integer> deq : deqs)
161            dits.addLast(deq.descendingIterator());
162        equal(dits);
163    }
164
165    private static void equal(Deque<Iterator<Integer>> its) {
166        Iterator<Integer> it0 = its.remove();
167        while (it0.hasNext()) {
168            Integer i = it0.next();
169            for (Iterator<Integer> it : its)
170                equal(it.next(), i);
171        }
172        for (Iterator<Integer> it : its) {
173            check(! it.hasNext());
174
175            try {it.next(); fail();}
176            catch (NoSuchElementException e) {pass();}
177            catch (Throwable t) {unexpected(t);}
178        }
179    }
180
181    //--------------------- Infrastructure ---------------------------
182    static volatile int passed = 0, failed = 0;
183    static void pass() {passed++;}
184    static void fail() {failed++; Thread.dumpStack();}
185    static void fail(String msg) {System.out.println(msg); fail();}
186    static void unexpected(Throwable t) {failed++; t.printStackTrace();}
187    static void check(boolean cond) {if (cond) pass(); else fail();}
188    static void equal(Object x, Object y) {
189        if (x == null ? y == null : x.equals(y)) pass();
190        else fail(x + " not equal to " + y);}
191    public static void main(String[] args) throws Throwable {
192        try {realMain(args);} catch (Throwable t) {unexpected(t);}
193        System.out.printf("%nPassed = %d, failed = %d%n%n", passed, failed);
194        if (failed > 0) throw new AssertionError("Some tests failed");}
195}
196