1 /*
   2  * Copyright (c) 1996, 2007, 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.awt.windows;
  26 
  27 abstract class WObjectPeer {
  28 
  29     static {
  30         initIDs();
  31     }
  32 
  33     long      pData;    // The Windows handle for the native widget.
  34     Object    target;   // The associated AWT object.
  35 
  36     private volatile boolean disposed;
  37 
  38     // set from JNI if any errors in creating the peer occur
  39     protected Error createError = null;
  40 
  41     public static WObjectPeer getPeerForTarget(Object t) {
  42         WObjectPeer peer = (WObjectPeer) WToolkit.targetToPeer(t);
  43         return peer;
  44     }
  45 
  46     public long getData() {
  47         return pData;
  48     }
  49 
  50     public Object getTarget() {
  51         return target;
  52     }
  53 
  54     /*
  55      * Subclasses should override disposeImpl() instead of dispose(). Client
  56      * code should always invoke dispose(), never disposeImpl().
  57      */
  58     abstract protected void disposeImpl();
  59     public final void dispose() {
  60         boolean call_disposeImpl = false;
  61 
  62         synchronized (this) {
  63             if (!disposed) {
  64                 disposed = call_disposeImpl = true;
  65             }
  66         }
  67 
  68         if (call_disposeImpl) {
  69             disposeImpl();
  70         }
  71     }
  72     protected final boolean isDisposed() {
  73         return disposed;
  74     }
  75 
  76     /**
  77      * Initialize JNI field and method IDs
  78      */
  79     private static native void initIDs();
  80 }