SoundSystemImpl.java

/*
 * $Id: SoundSystemImpl.java 536 2008-02-19 06:03:27Z weiju $
 * 
 * Created on 2006/01/29
 * Copyright 2005-2008 by Wei-ju Wu
 * This file is part of The Z-machine Preservation Project (ZMPP).
 *
 * ZMPP is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * ZMPP is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with ZMPP.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.zmpp.media;

import java.awt.Toolkit;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

import org.zmpp.base.Interruptable;

/**
 * This class implements the SoundSystem interface. The implementation is using
 * a Java 5 thread executor which makes it very easy to assign a control task to
 * each sound which can handle the stopping of a sound easily.
 *
 * @author Wei-ju Wu
 * @version 1.0
 */
public class SoundSystemImpl implements SoundSystem {

    /**
     * The resource database.
     */
    private MediaCollection<SoundEffect> sounds;

    /**
     * The executor service.
     */
    private ExecutorService executor;

    /**
     * The interruptable.
     */
    private Interruptable interruptable;

    /**
     * The current sound task.
     */
    protected PlaySoundTask currentTask;

    /**
     * Constructor.
     *
     * @param sounds the sound resources
     */
    public SoundSystemImpl(final MediaCollection<SoundEffect> sounds) {

        super();
        this.sounds = sounds;

    // That's pretty cool:
        // We can control the number of concurrent sounds to be played
        // simultaneously by the size of the thread pool.
        this.executor = Executors.newSingleThreadExecutor();
    }

    /**
     * This method handles the situation if a sound effect is going to be played
     * and a previous one is not finished.
     */
    protected void handlePreviousNotFinished() {

        // The default behaviour is to stop the previous sound
        currentTask.stop();
    }

    /**
     * {@inheritDoc}
     */
    public void reset() {

        // no resetting supported
    }

    /**
     * {@inheritDoc}
     */
    public void play(final int number, final int effect, final int volume,
            final int repeats, final int routine) {

        SoundEffect sound = null;

    // @sound_effect 0 3 followed by @sound_effect 0 4 is called
        // by "The Lurking Horror" and hints that all sound effects should
        // be stopped and unloaded. ZMPP's sound system implementation does
        // nothing at the moment (hey, we have plenty of memory and are
        // in a Java environment)
        if (number == 0) {
            return;
        }

        if (sounds != null) {
            sound = sounds.getResource(number);
        }
        if (sound == null) {

            Toolkit.getDefaultToolkit().beep();

        } else {

            if (effect == SoundSystem.EFFECT_START) {

                startSound(number, sound, volume, repeats, routine);

            } else if (effect == SoundSystem.EFFECT_STOP) {

                stopSound(number);

            } else if (effect == SoundSystem.EFFECT_PREPARE) {

                sounds.loadResource(number);

            } else if (effect == SoundSystem.EFFECT_FINISH) {

                stopSound(number);
                sounds.unloadResource(number);
            }
        }
    }

    /**
     * Starts the specified sound.
     *
     * @param number the sound number
     * @param sound the sound object
     * @param volume the volume
     * @param repeats the number of repeats
     * @param routine the interrupt routine
     */
    private void startSound(final int number, final SoundEffect sound,
            final int volume, final int repeats, final int routine) {

        if (currentTask != null && !currentTask.wasPlayed()) {

            handlePreviousNotFinished();
        }

        currentTask = (routine <= 0)
                ? new PlaySoundTask(number, sound, volume, repeats)
                : new PlaySoundTask(number, sound, volume, repeats, interruptable, routine);
        executor.submit(currentTask);
    }

    /**
     * Stops the sound with the given number.
     *
     * @param number the number
     */
    private void stopSound(final int number) {

        // only stop the sound if the numbers match
        if (currentTask != null && currentTask.getResourceNumber() == number) {

            currentTask.stop();
        }
    }
}