Showing the changes to java/pkg/sun/swing/BakedArrayList.java (1 of 18352 files). Show all
Unified · Split
| @@ -0,0 +1,93 @@ | |||
| 1 | /* | ||
| 2 | * Copyright (c) 2003, 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. Oracle designates this | ||
| 8 | * particular file as subject to the "Classpath" exception as provided | ||
| 9 | * by Oracle in the LICENSE file that accompanied this code. | ||
| 10 | * | ||
| 11 | * This code is distributed in the hope that it will be useful, but WITHOUT | ||
| 12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | ||
| 13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | ||
| 14 | * version 2 for more details (a copy is included in the LICENSE file that | ||
| 15 | * accompanied this code). | ||
| 16 | * | ||
| 17 | * You should have received a copy of the GNU General Public License version | ||
| 18 | * 2 along with this work; if not, write to the Free Software Foundation, | ||
| 19 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. | ||
| 20 | * | ||
| 21 | * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA | ||
| 22 | * or visit www.oracle.com if you need additional information or have any | ||
| 23 | * questions. | ||
| 24 | */ | ||
| 25 | package sun.swing; | ||
| 26 | |||
| 27 | import java.util.*; | ||
| 28 | |||
| 29 | /** | ||
| 30 | * <b>WARNING:</b> This class is an implementation detail and is only | ||
| 31 | * public so that it can be used by two packages. You should NOT consider | ||
| 32 | * this public API. | ||
| 33 | * <p> | ||
| 34 | * <b>WARNING 2:</b> This is not a general purpose List implementation! It | ||
| 35 | * has a specific use and will not work correctly if you use it outside of | ||
| 36 | * its use. | ||
| 37 | * <p> | ||
| 38 | * A specialized ArrayList that caches its hashCode as well as overriding | ||
| 39 | * equals to avoid creating an Iterator. This class is useful in scenarios | ||
| 40 | * where the list won't change and you want to avoid the overhead of hashCode | ||
| 41 | * iterating through the elements invoking hashCode. This also assumes you'll | ||
| 42 | * only ever compare a BakedArrayList to another BakedArrayList. | ||
| 43 | * | ||
| 44 | * @author Scott Violet | ||
| 45 | */ | ||
| 46 | public class BakedArrayList extends ArrayList { | ||
| 47 | /** | ||
| 48 | * The cached hashCode. | ||
| 49 | */ | ||
| 50 | private int _hashCode; | ||
| 51 | |||
| 52 | public BakedArrayList(int size) { | ||
| 53 | super(size); | ||
| 54 | } | ||
| 55 | |||
| 56 | public BakedArrayList(java.util.List data) { | ||
| 57 | this(data.size()); | ||
| 58 | for (int counter = 0, max = data.size(); counter < max; counter++){ | ||
| 59 | add(data.get(counter)); | ||
| 60 | } | ||
| 61 | cacheHashCode(); | ||
| 62 | } | ||
| 63 | |||
| 64 | /** | ||
| 65 | * Caches the hash code. It is assumed you won't modify the list, or that | ||
| 66 | * if you do you'll call cacheHashCode again. | ||
| 67 | */ | ||
| 68 | public void cacheHashCode() { | ||
| 69 | _hashCode = 1; | ||
| 70 | for (int counter = size() - 1; counter >= 0; counter--) { | ||
| 71 | _hashCode = 31 * _hashCode + get(counter).hashCode(); | ||
| 72 | } | ||
| 73 | } | ||
| 74 | |||
| 75 | public int hashCode() { | ||
| 76 | return _hashCode; | ||
| 77 | } | ||
| 78 | |||
| 79 | public boolean equals(Object o) { | ||
| 80 | BakedArrayList list = (BakedArrayList)o; | ||
| 81 | int size = size(); | ||
| 82 | |||
| 83 | if (list.size() != size) { | ||
| 84 | return false; | ||
| 85 | } | ||
| 86 | while (size-- > 0) { | ||
| 87 | if (!get(size).equals(list.get(size))) { | ||
| 88 | return false; | ||
| 89 | } | ||
| 90 | } | ||
| 91 | return true; | ||
| 92 | } | ||
| 93 | } | ||