Mega Code Archive
An example that plays a Midi sequence
<![CDATA[
/*
DEVELOPING GAME IN JAVA
Caracteristiques
Editeur : NEW RIDERS
Auteur : BRACKEEN
Parution : 09 2003
Pages : 972
Isbn : 1-59273-005-1
Reliure : Paperback
Disponibilite : Disponible a la librairie
*/
import java.io.BufferedInputStream;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import javax.sound.midi.InvalidMidiDataException;
import javax.sound.midi.MetaEventListener;
import javax.sound.midi.MetaMessage;
import javax.sound.midi.MidiSystem;
import javax.sound.midi.MidiUnavailableException;
import javax.sound.midi.Sequence;
import javax.sound.midi.Sequencer;
/**
* An example that plays a Midi sequence. First, the sequence is played once
* with track 1 turned off. Then the sequence is played once with track 1 turned
* on. Track 1 is the drum track in the example midi file.
*/
public class MidiTest implements MetaEventListener {
// The drum track in the example Midi file
private static final int DRUM_TRACK = 1;
public static void main(String[] args) {
new MidiTest().run();
}
private MidiPlayer player;
public void run() {
player = new MidiPlayer();
// load a sequence
Sequence sequence = player.getSequence("../sounds/music.midi");
// play the sequence
player.play(sequence, true);
// turn off the drums
System.out.println("Playing (without drums)...");
Sequencer sequencer = player.getSequencer();
sequencer.setTrackMute(DRUM_TRACK, true);
sequencer.addMetaEventListener(this);
}
/**
* This method is called by the sound system when a meta event occurs. In
* this case, when the end-of-track meta event is received, the drum track
* is turned on.
*/
public void meta(MetaMessage event) {
if (event.getType() == MidiPlayer.END_OF_TRACK_MESSAGE) {
Sequencer sequencer = player.getSequencer();
if (sequencer.getTrackMute(DRUM_TRACK)) {
// turn on the drum track
System.out.println("Turning on drums...");
sequencer.setTrackMute(DRUM_TRACK, false);
} else {
// close the sequencer and exit
System.out.println("Exiting...");
player.close();
System.exit(0);
}
}
}
}
class MidiPlayer implements MetaEventListener {
// Midi meta event
public static final int END_OF_TRACK_MESSAGE = 47;
private Sequencer sequencer;
private boolean loop;
private boolean paused;
/**
* Creates a new MidiPlayer object.
*/
public MidiPlayer() {
try {
sequencer = MidiSystem.getSequencer();
sequencer.open();
sequencer.addMetaEventListener(this);
} catch (MidiUnavailableException ex) {
sequencer = null;
}
}
/**
* Loads a sequence from the file system. Returns null if an error occurs.
*/
public Sequence getSequence(String filename) {
try {
return getSequence(new FileInputStream(filename));
} catch (IOException ex) {
ex.printStackTrace();
return null;
}
}
/**
* Loads a sequence from an input stream. Returns null if an error occurs.
*/
public Sequence getSequence(InputStream is) {
try {
if (!is.markSupported()) {
is = new BufferedInputStream(is);
}
Sequence s = MidiSystem.getSequence(is);
is.close();
return s;
} catch (InvalidMidiDataException ex) {
ex.printStackTrace();
return null;
} catch (IOException ex) {
ex.printStackTrace();
return null;
}
}
/**
* Plays a sequence, optionally looping. This method returns immediately.
* The sequence is not played if it is invalid.
*/
public void play(Sequence sequence, boolean loop) {
if (sequencer != null && sequence != null && sequencer.isOpen()) {
try {
sequencer.setSequence(sequence);
sequencer.start();
this.loop = loop;
} catch (InvalidMidiDataException ex) {
ex.printStackTrace();
}
}
}
/**
* This method is called by the sound system when a meta event occurs. In
* this case, when the end-of-track meta event is received, the sequence is
* restarted if looping is on.
*/
public void meta(MetaMessage event) {
if (event.getType() == END_OF_TRACK_MESSAGE) {
if (sequencer != null && sequencer.isOpen() && loop) {
sequencer.start();
}
}
}
/**
* Stops the sequencer and resets its position to 0.
*/
public void stop() {
if (sequencer != null && sequencer.isOpen()) {
sequencer.stop();
sequencer.setMicrosecondPosition(0);
}
}
/**
* Closes the sequencer.
*/
public void close() {
if (sequencer != null && sequencer.isOpen()) {
sequencer.close();
}
}
/**
* Gets the sequencer.
*/
public Sequencer getSequencer() {
return sequencer;
}
/**
* Sets the paused state. Music may not immediately pause.
*/
public void setPaused(boolean paused) {
if (this.paused != paused && sequencer != null && sequencer.isOpen()) {
this.paused = paused;
if (paused) {
sequencer.stop();
} else {
sequencer.start();
}
}
}
/**
* Returns the paused state.
*/
public boolean isPaused() {
return paused;
}
}
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