1 /*
   2  * Copyright (c) 2011, 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 
  26 package sun.lwawt.macosx;
  27 
  28 import sun.lwawt.LWCursorManager;
  29 
  30 import java.awt.Cursor;
  31 import java.awt.Point;
  32 import java.awt.geom.Point2D;
  33 
  34 final class CCursorManager extends LWCursorManager {
  35 
  36     private static native Point2D nativeGetCursorPosition();
  37     private static native void nativeSetBuiltInCursor(final int type, final String name);
  38     private static native void nativeSetCustomCursor(final long imgPtr, final double x, final double y);
  39 
  40     private static final int NAMED_CURSOR = -1;
  41 
  42     private static final CCursorManager theInstance = new CCursorManager();
  43     public static CCursorManager getInstance() {
  44         return theInstance;
  45     }
  46 
  47     private volatile Cursor currentCursor;
  48 
  49     private CCursorManager() { }
  50 
  51     @Override
  52     protected Point getCursorPosition() {
  53         synchronized(this) {
  54             if (isDragging) {
  55                 // during the drag operation, the appkit thread is blocked,
  56                 // so nativeGetCursorPosition invocation may cause a deadlock.
  57                 // In order to avoid this, we returns last know cursor position.
  58                 return new Point(dragPos);
  59             }
  60         }
  61 
  62         final Point2D nativePosition = nativeGetCursorPosition();
  63         return new Point((int)nativePosition.getX(), (int)nativePosition.getY());
  64     }
  65 
  66     @Override
  67     protected void setCursor(final Cursor cursor) {
  68         if (cursor == currentCursor) {
  69             return;
  70         }
  71         currentCursor = cursor;
  72 
  73         if (cursor == null) {
  74             nativeSetBuiltInCursor(Cursor.DEFAULT_CURSOR, null);
  75             return;
  76         }
  77 
  78         if (cursor instanceof CCustomCursor) {
  79             final CCustomCursor customCursor = (CCustomCursor) cursor;
  80             final long imagePtr = customCursor.getImageData();
  81             if (imagePtr != 0L) {
  82                 final Point hotSpot = customCursor.getHotSpot();
  83                 nativeSetCustomCursor(imagePtr, hotSpot.x, hotSpot.y);
  84             }
  85             return;
  86         }
  87 
  88         final int type = cursor.getType();
  89         if (type != Cursor.CUSTOM_CURSOR) {
  90             nativeSetBuiltInCursor(type, null);
  91             return;
  92         }
  93 
  94         final String name = cursor.getName();
  95         if (name != null) {
  96             nativeSetBuiltInCursor(NAMED_CURSOR, name);
  97             return;
  98         }
  99 
 100         // do something special
 101         throw new RuntimeException("Unimplemented");
 102     }
 103 
 104     // package private methods to handle cursor change during drag-and-drop
 105     private boolean isDragging = false;
 106     private Point dragPos = null;
 107 
 108     synchronized void startDrag(int x, int y) {
 109         if (isDragging) {
 110             throw new RuntimeException("Invalid Drag state in CCursorManager!");
 111         }
 112         isDragging = true;
 113         dragPos = new Point(x, y);
 114     }
 115 
 116     synchronized void updateDragPosition(int x, int y) {
 117         if (!isDragging) {
 118             throw new RuntimeException("Invalid Drag state in CCursorManager!");
 119         }
 120         dragPos.move(x, y);
 121     }
 122 
 123     synchronized void stopDrag() {
 124         if (!isDragging) {
 125             throw new RuntimeException("Invalid Drag state in CCursorManager!");
 126         }
 127         isDragging = false;
 128         dragPos = null;
 129     }
 130 }