soundbeeper.java

来自「google公司的用Java写的一个聊天软件的原代码」· Java 代码 · 共 232 行

/***************************************************************************
 *   Copyright 2006-2008 by Christian Ihle                                 *
 *   [e-mail]                                                  *
 *                                                                         *
 *   This program 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 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 *   This program 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 this program; if not, write to the                         *
 *   Free Software Foundation, Inc.,                                       *
 *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
 ***************************************************************************/

package net.usikkert.kouchat.misc;

import java.io.IOException;
import java.io.InputStream;

import java.util.logging.Level;
import java.util.logging.Logger;

import javax.sound.sampled.AudioFormat;
import javax.sound.sampled.AudioInputStream;
import javax.sound.sampled.Clip;
import javax.sound.sampled.DataLine;
import javax.sound.sampled.AudioSystem;
import javax.sound.sampled.LineUnavailableException;
import javax.sound.sampled.UnsupportedAudioFileException;

/**
 * Can load an audio file, and play it.
 *
 * @author Christian Ihle
 */
public class SoundBeeper
{
	private static final Logger LOG = Logger.getLogger( SoundBeeper.class.getName() );

	/**
	 * The file to play when beep() is run.
	 */
	private static final String BEEP_FILE = "/sounds/error.wav";

	/**
	 * The number of milliseconds to wait after
	 * beeping before closing.
	 */
	private static final int WAIT_PERIOD = 5000;

	private final Settings settings;
	private final ErrorHandler errorHandler;
	private Clip audioClip;
	private Thread closeTimer;
	private long closeTime;

	/**
	 * Default constructor.
	 */
	public SoundBeeper()
	{
		settings = Settings.getSettings();
		errorHandler = ErrorHandler.getErrorHandler();
	}

	/**
	 * Plays the loaded audio file if sound is enabled, and
	 * it's not already playing. If nothing has been played for
	 * 5 seconds the sound resource is released.
	 */
	public synchronized void beep()
	{
		if ( settings.isSound() )
		{
			if ( audioClip == null || !audioClip.isActive() )
			{
				if ( audioClip == null )
					open();
				else
					audioClip.setFramePosition( 0 );

				if ( audioClip != null )
				{
					audioClip.start();
					closeTime = System.currentTimeMillis() + WAIT_PERIOD;

					if ( closeTimer == null )
					{
						closeTimer = new Thread( new CloseTimer(), "SoundBeeperCloseTimer" );
						closeTimer.start();
					}
				}

				else
					LOG.log( Level.SEVERE, "Audio clip missing." );
			}
		}
	}

	/**
	 * Opens an audio file, and reserves the resources needed for playback.
	 */
	public void open()
	{
		InputStream resourceStream = getClass().getResourceAsStream( BEEP_FILE );

		if ( resourceStream != null )
		{
			AudioInputStream audioStream = null;

			try
			{
				audioStream = AudioSystem.getAudioInputStream( resourceStream );
				AudioFormat format = audioStream.getFormat();
				DataLine.Info info = new DataLine.Info( Clip.class, format );

				if ( AudioSystem.isLineSupported( info ) )
				{
					audioClip = (Clip) AudioSystem.getLine( info );
					audioClip.open( audioStream );
				}
			}

			catch ( final UnsupportedAudioFileException e )
			{
				LOG.log( Level.SEVERE, e.toString() );
				settings.setSound( false );
				errorHandler.showError( "Could not initialize the sound."
						+ "\nUnsupported file format: " + BEEP_FILE );
			}

			catch ( final IOException e )
			{
				LOG.log( Level.SEVERE, e.toString() );
				settings.setSound( false );
				errorHandler.showError( "Could not initialize the sound."
						+ "\nAudio file could not be opened: " + BEEP_FILE );
			}

			catch ( final LineUnavailableException e )
			{
				LOG.log( Level.WARNING, e.toString() );
			}

			finally
			{
				if ( resourceStream != null )
				{
					try
					{
						resourceStream.close();
					}

					catch ( final IOException e )
					{
						LOG.log( Level.WARNING, e.toString() );
					}
				}

				if ( audioStream != null )
				{
					try
					{
						audioStream.close();
					}

					catch ( final IOException e )
					{
						LOG.log( Level.WARNING, e.toString() );
					}
				}
			}
		}

		else
		{
			LOG.log( Level.SEVERE, "Audio file not found: " + BEEP_FILE );
			settings.setSound( false );
			errorHandler.showError( "Could not initialize the sound."
					+ "\nAudio file not found: " + BEEP_FILE );
		}
	}

	/**
	 * Closes the audio file and frees the resources used.
	 */
	public void close()
	{
		if ( audioClip != null )
		{
			audioClip.flush();
			audioClip.close();
			audioClip = null;
		}
	}

	/**
	 * A simple thread used for freeing sound resources when finished.
	 *
	 * @author Christian Ihle
	 */
	private class CloseTimer implements Runnable
	{
		@Override
		public void run()
		{
			while ( System.currentTimeMillis() < closeTime )
			{
				try
				{
					Thread.sleep( 1000 );
				}

				catch ( final InterruptedException e )
				{
					LOG.log( Level.WARNING, e.toString() );
				}
			}

			close();
			closeTimer = null;
		}
	}
}