/* * 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:</b> 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:</b> 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; }}
/*
* 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:</b> 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:</b> 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;
}
}