1 /*

     2  * Copyright 2003-2008 Sun Microsystems, Inc.  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.  Sun designates this

     8  * particular file as subject to the "Classpath" exception as provided

     9  * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

    22  * CA 95054 USA or visit www.sun.com if you need additional information or

    23  * have any questions.

    24  */

    25 

    26 package sun.java2d;

    27 

    28 import sun.awt.image.SunVolatileImage;

    29 import sun.awt.image.VolatileSurfaceManager;

    30 

    31 /**

    32  * This factory creates platform specific VolatileSurfaceManager

    33  * implementations.

    34  *

    35  * There are two platform specific SurfaceManagerFactories in OpenJDK,

    36  * UnixSurfaceManagerFactory and WindowsSurfaceManagerFactory.

    37  * The actually used SurfaceManagerFactory is set by the respective platform

    38  * GraphicsEnvironment implementations in the static initializer.

    39  */

    40 public abstract class SurfaceManagerFactory {

    41 

    42     /**

    43      * The single shared instance.

    44      */

    45     private static SurfaceManagerFactory instance;

    46 

    47     /**

    48      * Returns the surface manager factory instance. This returns a factory

    49      * that has been set by {@link #setInstance(SurfaceManagerFactory)}.

    50      *

    51      * @return the surface manager factory

    52      */

    53     public synchronized static SurfaceManagerFactory getInstance() {

    54 

    55         if (instance == null) {

    56             throw new IllegalStateException("No SurfaceManagerFactory set.");

    57         }

    58         return instance;

    59     }

    60 

    61     /**

    62      * Sets the surface manager factory. This may only be called once, and it

    63      * may not be set back to {@code null} when the factory is already

    64      * instantiated.

    65      *

    66      * @param factory the factory to set

    67      */

    68     public synchronized static void setInstance(SurfaceManagerFactory factory) {

    69 

    70         if (factory == null) {

    71             // We don't want to allow setting this to null at any time.

    72             throw new IllegalArgumentException("factory must be non-null");

    73         }

    74 

    75         if (instance != null) {

    76             // We don't want to re-set the instance at any time.

    77             throw new IllegalStateException("The surface manager factory is already initialized");

    78         }

    79 

    80         instance = factory;

    81     }

    82 

    83     /**

    84      * Creates a new instance of a VolatileSurfaceManager given any

    85      * arbitrary SunVolatileImage.  An optional context Object can be supplied

    86      * as a way for the caller to pass pipeline-specific context data to

    87      * the VolatileSurfaceManager (such as a backbuffer handle, for example).

    88      */

    89      public abstract VolatileSurfaceManager

    90          createVolatileManager(SunVolatileImage image, Object context);

    91 }