I'm currently writing a basic musical chairs application and have run into some difficulty while turning on/off music using a button (in my beautiful swing interface).
I created the interface in netbeans, and have added the necessary action listeners. Below is the relevant code:
*private void runActionPerformed(java.awt.event.ActionEvent evt) {
if (run.getText().equals("Stop Music"))
stopMus();
else
startMus();
}
public void startMus()
{
Music music = new Music();
music.playAudio();
run.setText("Stop Music");
}
public void stopMus()
{
Music music = new Music();
music.stopAudio();
run.setText("Start Music");
}*
The class "Music" is as follows:
import java.io.File;
import javax.sound.sampled.AudioFormat;
import javax.sound.sampled.AudioInputStream;
import javax.sound.sampled.AudioSystem;
import javax.sound.sampled.DataLine;
import javax.sound.sampled.SourceDataLine;
public class Music {
AudioFormat audioFormat;
AudioInputStream audioInputStream;
SourceDataLine sourceDataLine;
boolean stopPlayback = false;
playThread p;
public Music()
{
p = new playThread();
}
public void playAudio()
{
try {
File soundFile = new File("music.mp3"); //file to play
audioInputStream = AudioSystem.getAudioInputStream(soundFile); // start a stream
audioFormat = audioInputStream.getFormat(); //finds format of file
DataLine.Info dli = new DataLine.Info(SourceDataLine.class, audioFormat); //creates a buffer to play
sourceDataLine =(SourceDataLine)AudioSystem.getLine(dli); //as above
} catch (Exception e)
{
System.out.println(e.getMessage());
}
p.start();
}
public void stopAudio()
{
p.stopT();
}
private class playThread extends Thread
{
byte[] tempBuffer = new byte[10000];
@Override public void run(){
try{
sourceDataLine.open(audioFormat);
sourceDataLine.start();
int cnt;
//loop while buffer isn't empty
while((cnt = audioInputStream.read(tempBuffer,0,tempBuffer.length)) != -1 && stopPlayback == false){
if(cnt > 0)
sourceDataLine.write(tempBuffer, 0, cnt);
}
sourceDataLine.drain();
sourceDataLine.close();
stopPlayback = false;
}catch (Exception e) {
System.out.println(e.getMessage());
System.exit(0);
}
}
public void stopT()
{
this.interrupt();
}
}
}
The error I'm getting is a pretty strange one! (and long)
Exception in thread "AWT-EventQueue-0" java.lang.RuntimeException: Uncompilable source code - Erroneous tree type: coursework.Music
at coursework.JFrameThing.startMus(JFrameThing.java:57)
at coursework.JFrameThing.runActionPerformed(JFrameThing.java:51)
at coursework.JFrameThing.access$000(JFrameThing.java:3)
at coursework.JFrameThing$1.actionPerformed(JFrameThing.java:23)
at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2012)
at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2335)
at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:404)
at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:259)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:252)
at java.awt.Component.processMouseEvent(Component.java:6288)
at javax.swing.JComponent.processMouseEvent(JComponent.java:3267)
at java.awt.Component.processEvent(Component.java:6053)
at java.awt.Container.processEvent(Container.java:2045)
at java.awt.Component.dispatchEventImpl(Component.java:4649)
at java.awt.Container.dispatchEventImpl(Container.java:2103)
at java.awt.Component.dispatchEvent(Component.java:4475)
at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4633)
at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4297)
at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4227)
at java.awt.Container.dispatchEventImpl(Container.java:2089)
at java.awt.Window.dispatchEventImpl(Window.java:2587)
at java.awt.Component.dispatchEvent(Component.java:4475)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:675)
at java.awt.EventQueue.access$300(EventQueue.java:96)
at java.awt.EventQueue$2.run(EventQueue.java:634)
at java.awt.EventQueue$2.run(EventQueue.java:632)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:105)
at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:116)
at java.awt.EventQueue$3.run(EventQueue.java:648)
at java.awt.EventQueue$3.run(EventQueue.java:646)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:105)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:645)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:275)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:200)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:190)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:185)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:177)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:138)
After some googling, it is allegedly an archaic one; it also points to my instantiation of the Music object (Music music = new Music();) but I can't understand why that would cause an issue! I know that my threading isn't as efficient as it could be, but surely that wouldn't cause this problem?
