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.ArrayDeque; 32import java.util.Collection; 33import java.util.Deque; 34import java.util.Iterator; 35import java.util.LinkedList; 36import java.util.NoSuchElementException; 37import java.util.concurrent.ConcurrentLinkedDeque; 38import java.util.concurrent.LinkedBlockingDeque; 39 40public class ChorusLine { 41 private interface Tweaker { 42 void run(Deque<Integer> deq); 43 } 44 45 private static final Tweaker[] tweakers = { 46 new Tweaker() { public void run(Deque<Integer> deq) { 47 for (int i = 0; i < 7; i++) 48 deq.addLast(i); 49 deq.removeFirst(); 50 deq.removeFirst(); 51 deq.addLast(7); 52 deq.addLast(8); 53 Iterator<Integer> it = deq.descendingIterator(); 54 equal(it.next(), 8); 55 it.remove(); 56 57 try {it.remove();} 58 catch (IllegalStateException e) {pass();} 59 catch (Throwable t) {unexpected(t);} 60 61 deq.addLast(9); 62 it = deq.descendingIterator(); 63 equal(it.next(), 9); 64 equal(it.next(), 7); 65 it.remove(); 66 67 try {it.remove();} 68 catch (IllegalStateException e) {pass();} 69 catch (Throwable t) {unexpected(t);} 70 71 equal(it.next(), 6); 72 73 System.out.println(deq); 74 }}, 75 new Tweaker() { public void run(Deque<Integer> deq) { 76 deq.clear(); 77 check(deq.isEmpty()); 78 check(deq.size() == 0); 79 check(! deq.iterator().hasNext()); 80 check(! deq.descendingIterator().hasNext()); 81 82 try {deq.iterator().next(); fail();} 83 catch (NoSuchElementException e) {pass();} 84 catch (Throwable t) {unexpected(t);} 85 86 try {deq.descendingIterator().next(); fail();} 87 catch (NoSuchElementException e) {pass();} 88 catch (Throwable t) {unexpected(t);} 89 }}, 90 new Tweaker() { public void run(Deque<Integer> deq) { 91 for (int i = 0; i < 11; i++) 92 deq.add(i); 93 Iterator<Integer> it = deq.iterator(); 94 equal(it.next(), 0); 95 equal(it.next(), 1); 96 it.remove(); 97 deq.addFirst(-1); 98 deq.addFirst(-2); 99 it = deq.iterator(); 100 equal(it.next(), -2); 101 equal(it.next(), -1); 102 equal(it.next(), 0); 103 it.remove(); 104 105 it = deq.descendingIterator(); 106 107 try {it.remove(); fail();} 108 catch (IllegalStateException e) {pass();} 109 catch (Throwable t) {unexpected(t);} 110 111 equal(it.next(), 10); 112 it.remove(); 113 114 try {it.remove(); fail();} 115 catch (IllegalStateException e) {pass();} 116 catch (Throwable t) {unexpected(t);} 117 118 equal(it.next(), 9); 119 equal(it.next(), 8); 120 it.remove(); 121 System.out.println(deq); 122 }}, 123 new Tweaker() { public void run(Deque<Integer> deq) { 124 while (deq.size() > 1) { 125 Iterator<Integer> it = deq.iterator(); 126 it.next(); it.remove(); 127 it = deq.descendingIterator(); 128 it.next(); it.remove(); 129 } 130 System.out.println(deq); 131 }}}; 132 133 private static void realMain(String[] args) throws Throwable { 134 Collection<Deque<Integer>> deqs = new ArrayDeque<>(3); 135 deqs.add(new ArrayDeque<Integer>()); 136 deqs.add(new LinkedList<Integer>()); 137 deqs.add(new LinkedBlockingDeque<Integer>()); 138 deqs.add(new ConcurrentLinkedDeque<Integer>()); 139 140 equal(deqs); 141 142 for (Tweaker tweaker : tweakers) { 143 for (Deque<Integer> deq : deqs) 144 tweaker.run(deq); 145 equal(deqs); 146 } 147 } 148 149 private static void equal(Iterable<Deque<Integer>> deqs) { 150 Deque<Integer> prev = null; 151 for (Deque<Integer> deq : deqs) { 152 if (prev != null) { 153 equal(prev.isEmpty(), deq.isEmpty()); 154 equal(prev.size(), deq.size()); 155 equal(prev.toString(), deq.toString()); 156 } 157 prev = deq; 158 } 159 160 Deque<Iterator<Integer>> its = new ArrayDeque<>(); 161 for (Deque<Integer> deq : deqs) 162 its.addLast(deq.iterator()); 163 equal(its); 164 165 Deque<Iterator<Integer>> dits = new ArrayDeque<>(); 166 for (Deque<Integer> deq : deqs) 167 dits.addLast(deq.descendingIterator()); 168 equal(dits); 169 } 170 171 private static void equal(Deque<Iterator<Integer>> its) { 172 Iterator<Integer> it0 = its.remove(); 173 while (it0.hasNext()) { 174 Integer i = it0.next(); 175 for (Iterator<Integer> it : its) 176 equal(it.next(), i); 177 } 178 for (Iterator<Integer> it : its) { 179 check(! it.hasNext()); 180 181 try {it.next(); fail();} 182 catch (NoSuchElementException e) {pass();} 183 catch (Throwable t) {unexpected(t);} 184 } 185 } 186 187 //--------------------- Infrastructure --------------------------- 188 static volatile int passed = 0, failed = 0; 189 static void pass() {passed++;} 190 static void fail() {failed++; Thread.dumpStack();} 191 static void fail(String msg) {System.out.println(msg); fail();} 192 static void unexpected(Throwable t) {failed++; t.printStackTrace();} 193 static void check(boolean cond) {if (cond) pass(); else fail();} 194 static void equal(Object x, Object y) { 195 if (x == null ? y == null : x.equals(y)) pass(); 196 else fail(x + " not equal to " + y);} 197 public static void main(String[] args) throws Throwable { 198 try {realMain(args);} catch (Throwable t) {unexpected(t);} 199 System.out.printf("%nPassed = %d, failed = %d%n%n", passed, failed); 200 if (failed > 0) throw new AssertionError("Some tests failed");} 201} 202