1 /*
2  * Copyright (c) 2003, 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.awt.image;
27 
28 import sun.java2d.SurfaceData;
29 
30 /**
31  * This SurfaceManager variant manages an unaccelerated volatile surface.
32  * This class is created in the event that someone requested a VolatileImage
33  * to be created from a BufferedImageGraphicsConfig, which is not platform-
34  * or hardware-based, thus the resulting surface and surface manager
35  * are unaccelerated.  All we do in this class is implement the abstract
36  * methods of VolatileSurfaceManager to return values that indicate that
37  * we cannot accelerate surfaces through this SurfaceManager, thus the
38  * parent class will handle things through the unaccelerated backup mechanism.
39  */
40 public class BufImgVolatileSurfaceManager extends VolatileSurfaceManager {
41 
42     /**
43      * This constructor simply defers to the superclass since all of the real
44      * functionality of this class is implemented in VolatileSurfaceManager.
45      */
BufImgVolatileSurfaceManager(SunVolatileImage vImg, Object context)46     public BufImgVolatileSurfaceManager(SunVolatileImage vImg, Object context) {
47         super(vImg, context);
48     }
49 
50     /**
51      * Returns false to indicate that this surface manager cannot accelerate
52      * the image.
53      */
isAccelerationEnabled()54     protected boolean isAccelerationEnabled() {
55         return false;
56     }
57 
58     /**
59      * Returns null to indicate failure in creating the accelerated surface.
60      * Note that this method should not ever be called since creation of
61      * accelerated surfaces should be preceded by calls to the above
62      * isAccelerationEnabled() method.  But we need to override this method
63      * since it is abstract in our parent class.
64      */
initAcceleratedSurface()65     protected SurfaceData initAcceleratedSurface() {
66         return null;
67     }
68 }
69