import javax.sound.midi.*;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

public class Noodirakend7 extends JApplet implements ActionListener, MetaEventListener{
  Sequence sequence;
  Sequencer sequencer;
  JButton nupp=new JButton("Mängi");
  JCheckBox ruut=new JCheckBox("Korda");
  
  void looKolmkola(Track t, int toonika){
  try{
   ShortMessage m[]=new ShortMessage[7];
   for(int i=0; i<m.length; i++){
     m[i]=new ShortMessage();  		// Tühjad teated valmis
   }  
   m[0].setMessage(ShortMessage.PROGRAM_CHANGE, 0, 25, 0);  //pill nr 25 rajale 0
   m[1].setMessage(ShortMessage.NOTE_ON, 0, toonika, 60);
   m[2].setMessage(ShortMessage.NOTE_ON, 0, toonika+4, 60); //terts rajale 0 valjusega 60
   m[3].setMessage(ShortMessage.NOTE_ON, 0, toonika+7, 60); //kvint
   m[4].setMessage(ShortMessage.NOTE_OFF, 0, toonika, 60);
   m[5].setMessage(ShortMessage.NOTE_OFF, 0, toonika+4, 60);
   m[6].setMessage(ShortMessage.NOTE_OFF, 0, toonika+7, 60);
    t.add(new MidiEvent(m[0], 0));
   for(int i=1; i<4; i++){
     t.add(new MidiEvent(m[i], (i-1)*4));  // nelja tiksu (ühe löögi) tagant
   }                                       // noodid sisse
   for(int i=4; i<7; i++){
     t.add(new MidiEvent(m[i], 12));       // 12nda tiksu juures vaikus
   }
  }catch(Exception e){
    e.printStackTrace();
  }
 }
  
  public void init(){
    try{
         sequence=new Sequence(Sequence.PPQ, 4);
         Track track=sequence.createTrack();
         looKolmkola(track, 60); // C-duuri kolmkõla
         
         getContentPane().add(nupp, BorderLayout.SOUTH);
         getContentPane().add(ruut, BorderLayout.NORTH);
         nupp.addActionListener(this);
      }catch(Exception e){e.printStackTrace();}
  }

  public void actionPerformed(ActionEvent e){
   try{
         sequencer=MidiSystem.getSequencer();
         sequencer.open();
         sequencer.setSequence(sequence);
         sequencer.addMetaEventListener(this);
         sequencer.start();
   }catch(Exception ex){
     ex.printStackTrace();
     System.out.println(ex);
   }
  }
  
  public void meta(MetaMessage m){
    if(m.getType()==47 && ruut.isSelected()){
      sequencer.start();
    } else {
      sequencer.close();
    }
  }
  
  public static void main(String argumendid[]){
    JFrame f=new JFrame("Kolmkõla");
    Noodirakend7 ap=new Noodirakend7();
    ap.init();
    f.getContentPane().add(ap);
    f.setSize(200, 100);
    f.setVisible(true);
  }
}