javax.media.j3d.IndexedObject Maven / Gradle / Ivy
/*
* Copyright 2001-2008 Sun Microsystems, Inc. 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. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*
*/
package javax.media.j3d;
/**
* Class used for IndexedUnorderedList
*/
abstract class IndexedObject extends Object {
/**
* A 2D array listIdx[3][len] is used.
* The entry listIdx[0][], listIdx[0][1] is used for each VirtualUniverse.
* The entry listIdx[2][0] is used for index to which one to use.
*
* This is used to handle the case the Node Object move from
* one VirtualUniverse A to another VirtualUniverse B.
* It is possible that another Structures in B may get the add
* message first before the Structures in A get the remove
* message to clear the entry. This cause MT problem. So a
* 2D array is used to resolve it.
*/
int[][] listIdx;
abstract VirtualUniverse getVirtualUniverse();
synchronized int getIdxUsed(VirtualUniverse u) {
int idx = listIdx[2][0];
if (u == getVirtualUniverse()) {
return idx;
}
return (idx == 0 ? 1 : 0);
}
void incIdxUsed() {
if (listIdx[2][0] == 0) {
listIdx[2][0] = 1;
} else {
listIdx[2][0] = 0;
}
}
}