Da questo listato non riesco a sentire il file che vorrei:
codice:
import javax.swing.*;
import javax.sound.midi.*;
import java.awt.GridLayout;
import java.io.File;
import javax.sound.midi.*;

public class PlayMidi1 extends JFrame {
    String song="set_fire1.wav";
    
    PlayMidi1() {
        super("Play MIDI Files");
        setSize(180, 100);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        MidiPanel1 midi = new MidiPanel1(song);
        JPanel pane = new JPanel();
        pane.add(midi);
        setContentPane(pane);
        setVisible(true);
    }

    public static void main(String[] args) {
        
            PlayMidi1 pm = new PlayMidi1();
            
       
    }
}

class MidiPanel1 extends JPanel implements Runnable {
    Thread runner;
    JProgressBar progress = new JProgressBar();
    Sequence currentSound;
    Sequencer player;
    String songFile;

    MidiPanel1(String song) {
        super();
        songFile = song;
        JLabel label = new JLabel("Playing file ...");
        setLayout(new GridLayout(2, 1));
        add(label);
        add(progress);
        if (runner == null) {
            runner = new Thread(this);
            runner.start();
        }
    }

    public void run() {
        try {
            
            File file = new File("set_fire1.wav");
            
            currentSound = MidiSystem.getSequence(file);
            
            player = MidiSystem.getSequencer();
            player.open();
            player.setSequence(currentSound);
            progress.setMinimum(0);
            progress.setMaximum((int)player.getMicrosecondLength());
            player.start();
            while (player.isRunning()) {
                progress.setValue((int)player.getMicrosecondPosition());
                try {
                    Thread.sleep(1000);
                } catch (Exception e) {e.printStackTrace(); }
            }
            progress.setValue((int)player.getMicrosecondPosition());
            player.close();
        } catch (Exception ex) {
            System.out.println(ex.getMessage());
            System.out.println(currentSound);
        }
    }
}

Mi da questo errore:
could not get sequence from file
null.
Presumo sia l'istruzione:
currentSound = MidiSystem.getSequence(file);
Forse il formato del file non è giusto?Grazie