1 /*
  2  * Copyright (c) 2012, 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  * Portions Copyright (c) 2012 IBM Corporation
 26  */
 27 
 28 /*
 29  * @test
 30  * @bug 8000955
 31  * @summary Map.Entry implementations need to comply with Map.Entry.hashCode() defined behaviour.
 32  * @author ngmr
 33  */
 34 import java.util.*;
 35 import java.util.concurrent.ConcurrentHashMap;
 36 import java.util.concurrent.ConcurrentSkipListMap;
 37 
 38 public class EntryHashCode {
 39     private static final int TEST_SIZE = 100;
 40 
 41     static final Object[][] entryData = {
 42         new Object[TEST_SIZE],
 43         new Object[TEST_SIZE]
 44     };
 45 
 46     @SuppressWarnings("unchecked")
 47     static final Map<Object,Object>[] maps = (Map<Object,Object>[])new Map[] {
 48         new HashMap<>(),
 49         new Hashtable<>(),
 50         new IdentityHashMap<>(),
 51         new LinkedHashMap<>(),
 52         new TreeMap<>(),
 53         new WeakHashMap<>(),
 54         new ConcurrentHashMap<>(),
 55         new ConcurrentSkipListMap<>()
 56     };
 57 
 58     static {
 59         for (int i = 0; i < entryData[0].length; i++) {
 60             // key objects need to be Comparable for use in TreeMap
 61             entryData[0][i] = new Comparable<Object>() {
 62                 public int compareTo(Object o) {
 63                     return (hashCode() - o.hashCode());
 64                 }
 65             };
 66             entryData[1][i] = new Object();
 67         }
 68     }
 69 
 70     private static void addTestData(Map<Object,Object> map) {
 71         for (int i = 0; i < entryData[0].length; i++) {
 72             map.put(entryData[0][i], entryData[1][i]);
 73         }
 74     }
 75 
 76     public static void main(String[] args) throws Exception {
 77         Exception failure = null;
 78         for (Map<Object,Object> map: maps) {
 79             addTestData(map);
 80 
 81             try {
 82                 for (Map.Entry<Object,Object> e: map.entrySet()) {
 83                     Object key = e.getKey();
 84                     Object value = e.getValue();
 85                     int expectedEntryHashCode =
 86                         (Objects.hashCode(key) ^ Objects.hashCode(value));
 87 
 88                     if (e.hashCode() != expectedEntryHashCode) {
 89                         throw new Exception("FAILURE: " +
 90                                 e.getClass().getName() +
 91                                 ".hashCode() does not conform to defined" +
 92                                 " behaviour of java.util.Map.Entry.hashCode()");
 93                     }
 94                 }
 95             } catch (Exception e) {
 96                 if (failure == null) {
 97                     failure = e;
 98                 } else {
 99                     failure.addSuppressed(e);
100                 }
101             } finally {
102                 map.clear();
103             }
104         }
105         if (failure != null) {
106             throw failure;
107         }
108     }
109 }