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     public static native void nativeSetAllowsCursorSetInBackground(final boolean allows);
  40 
  41     private static final int NAMED_CURSOR = -1;
  42 
  43     private static final CCursorManager theInstance = new CCursorManager();
  44     public static CCursorManager getInstance() {
  45         return theInstance;
  46     }
  47 
  48     private volatile Cursor currentCursor;
  49 
  50     private CCursorManager() { }
  51 
  52     @Override
  53     protected Point getCursorPosition() {
  54         synchronized(this) {
  55             if (isDragging) {
  56                 // during the drag operation, the appkit thread is blocked,
  57                 // so nativeGetCursorPosition invocation may cause a deadlock.
  58                 // In order to avoid this, we returns last know cursor position.
  59                 return new Point(dragPos);
  60             }
  61         }
  62 
  63         final Point2D nativePosition = nativeGetCursorPosition();
  64         return new Point((int)nativePosition.getX(), (int)nativePosition.getY());
  65     }
  66 
  67     @Override
  68     protected void setCursor(final Cursor cursor) {
  69         if (cursor == currentCursor) {
  70             return;
  71         }
  72         currentCursor = cursor;
  73 
  74         if (cursor == null) {
  75             nativeSetBuiltInCursor(Cursor.DEFAULT_CURSOR, null);
  76             return;
  77         }
  78 
  79         if (cursor instanceof CCustomCursor) {
  80             final CCustomCursor customCursor = (CCustomCursor) cursor;
  81             final long imagePtr = customCursor.getImageData();
  82             if (imagePtr != 0L) {
  83                 final Point hotSpot = customCursor.getHotSpot();
  84                 nativeSetCustomCursor(imagePtr, hotSpot.x, hotSpot.y);
  85             }
  86             return;
  87         }
  88 
  89         final int type = cursor.getType();
  90         if (type != Cursor.CUSTOM_CURSOR) {
  91             nativeSetBuiltInCursor(type, null);
  92             return;
  93         }
  94 
  95         final String name = cursor.getName();
  96         if (name != null) {
  97             nativeSetBuiltInCursor(NAMED_CURSOR, name);
  98             return;
  99         }
 100 
 101         // do something special
 102         throw new RuntimeException("Unimplemented");
 103     }
 104 
 105     // package private methods to handle cursor change during drag-and-drop
 106     private boolean isDragging = false;
 107     private Point dragPos = null;
 108 
 109     synchronized void startDrag(int x, int y) {
 110         if (isDragging) {
 111             throw new RuntimeException("Invalid Drag state in CCursorManager!");
 112         }
 113         isDragging = true;
 114         dragPos = new Point(x, y);
 115     }
 116 
 117     synchronized void updateDragPosition(int x, int y) {
 118         if (!isDragging) {
 119             throw new RuntimeException("Invalid Drag state in CCursorManager!");
 120         }
 121         dragPos.move(x, y);
 122     }
 123 
 124     synchronized void stopDrag() {
 125         if (!isDragging) {
 126             throw new RuntimeException("Invalid Drag state in CCursorManager!");
 127         }
 128         isDragging = false;
 129         dragPos = null;
 130     }
 131 }