alfactory.java

Jake2是一个Java 3D游戏引擎.

/**
 * Copyright (c) 2003 Sun Microsystems, Inc. All  Rights Reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * -Redistribution of source code must retain the above copyright notice, 
 * this list of conditions and the following disclaimer.
 *
 * -Redistribution in binary form must reproduce the above copyright notice, 
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * Neither the name of Sun Microsystems, Inc. or the names of contributors may 
 * be used to endorse or promote products derived from this software without 
 * specific prior written permission.
 * 
 * This software is provided "AS IS," without a warranty of any kind.
 * ALL EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING
 * ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR
 * NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN MIDROSYSTEMS, INC. ("SUN") AND ITS
 * LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE AS A
 * RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES.
 * IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR ANY LOST REVENUE, PROFIT
 * OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL, INCIDENTAL OR
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 * ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE, EVEN IF SUN HAS
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 *
 * You acknowledge that this software is not designed or intended for use in the
 * design, construction, operation or maintenance of any nuclear facility.
 */

package net.java.games.joal;

/**
 * This class provides factory methods for generating AL and ALC objects. The
 * class must be initialized before use, and should be deinitialized when OpenAL
 * functionality is no longer needed to free up native resources.
 * 
 * @author Athomas Goldberg
 */
public class ALFactory {
    static {
        System.loadLibrary("joal");
    }

    private static boolean isInitialized = false;

    private static ALImpl al;

    private static ALC alc;

    /**
     * Initialize the OpenAL environment
     * 
     * @return true is OpenAL was able to initialize, false if OpenAL was not
     *             able to intialize
     */
    public static boolean initialize() throws OpenALException {
        String osProperty = System.getProperty("os.name");
        if (osProperty.startsWith("Win")) {
            isInitialized = init(new String[] { "OpenAL32.dll" });
        } else if (osProperty.startsWith("Linux")) {
            try {
                // use the system wide lib
                isInitialized = init(new String[] { "libopenal.so" });
            } catch (OpenALException e) {
                // fallback to bytonic's libopenal.so
                String sep = System.getProperty("file.separator");
                String openalPath = System.getProperty("user.home") + sep + ".jake2";
                isInitialized = init(new String[] { openalPath + sep
                        + "libopenal.so" });
            }
        } else {
            isInitialized = init(new String[] { "/Library/Frameworks/OpenAL.framework/Versions/Current/OpenAL" });
        }
        return isInitialized;
    }

    private static native boolean init(String[] oalPaths)
            throws OpenALException;

    /**
     * Deinitialize the OpenAL environment
     * 
     * @return true if OpenAL was able to be deinitialized, false if OpenAL uas
     *             unable to be deinitialized
     */
    public static native boolean deinitialize();

    /**
     * Get the default AL object. This object is used to access most of the
     * OpenAL functionality.
     * 
     * @return the AL object
     */
    public static AL getAL() throws OpenALException {
        if (!isInitialized) {
            initialize();
        }
        if (isInitialized && al == null) {
            al = new ALImpl();
        }
        return al;
    }

    /**
     * Get the default ALC object. This object is used to access most of the
     * OpenAL context functionality.
     * 
     * @return the ALC object
     */
    public static ALC getALC() throws OpenALException {
        if (!isInitialized) {
            initialize();
        }
        if (isInitialized && alc == null) {
            alc = new ALCImpl();
        }
        return alc;
    }
}