|
Java example source code file (BakedArrayList.java)
The BakedArrayList.java Java example source code/* * Copyright (c) 2003, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package sun.swing; import java.util.*; /** * <b>WARNING: This class is an implementation detail and is only * public so that it can be used by two packages. You should NOT consider * this public API. * <p> * <b>WARNING 2: This is not a general purpose List implementation! It * has a specific use and will not work correctly if you use it outside of * its use. * <p> * A specialized ArrayList that caches its hashCode as well as overriding * equals to avoid creating an Iterator. This class is useful in scenarios * where the list won't change and you want to avoid the overhead of hashCode * iterating through the elements invoking hashCode. This also assumes you'll * only ever compare a BakedArrayList to another BakedArrayList. * * @author Scott Violet */ public class BakedArrayList extends ArrayList { /** * The cached hashCode. */ private int _hashCode; public BakedArrayList(int size) { super(size); } public BakedArrayList(java.util.List data) { this(data.size()); for (int counter = 0, max = data.size(); counter < max; counter++){ add(data.get(counter)); } cacheHashCode(); } /** * Caches the hash code. It is assumed you won't modify the list, or that * if you do you'll call cacheHashCode again. */ public void cacheHashCode() { _hashCode = 1; for (int counter = size() - 1; counter >= 0; counter--) { _hashCode = 31 * _hashCode + get(counter).hashCode(); } } public int hashCode() { return _hashCode; } public boolean equals(Object o) { BakedArrayList list = (BakedArrayList)o; int size = size(); if (list.size() != size) { return false; } while (size-- > 0) { if (!get(size).equals(list.get(size))) { return false; } } return true; } } Other Java examples (source code examples)Here is a short list of links related to this Java BakedArrayList.java source code file: |
... this post is sponsored by my books ... | |
#1 New Release! |
FP Best Seller |
Copyright 1998-2024 Alvin Alexander, alvinalexander.com
All Rights Reserved.
A percentage of advertising revenue from
pages under the /java/jwarehouse
URI on this website is
paid back to open source projects.