I have written this code for a simple music player, the problem is that when I click openLabel and open a song and then when I pause it by clicking playLabel the program stops execution (program hangs).
import java.awt.*;
import java.awt.event.*;
import java.io.File;
import java.util.Random;
import javax.sound.sampled.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.filechooser.FileNameExtensionFilter;
public class A extends MouseAdapter implements ChangeListener, Runnable {
private ImageIcon playImage = new ImageIcon(getClass().getResource("Images/play.png"));
private ImageIcon pauseImage = new ImageIcon(getClass().getResource("Images/pause.png"));
private ImageIcon openImage = new ImageIcon(getClass().getResource("Images/open.png"));
private JLabel playLabel = new JLabel(playImage);
private JLabel openLabel = new JLabel(openImage);
public JFrame frame = new JFrame();
public JPanel colorPanel = new JPanel();
private enum Status {ON,OFF,PAUSE,END};
private Status playStatus=Status.OFF;
private JSlider slider = new JSlider();
public Clip songClip;
Thread screenThread = new Thread(this);
public static void main(String arg[]) throws Exception {
new A();
}
public A() throws Exception {
setFrame();
setComponents();
}
public void setFrame() {
frame.setExtendedState(JFrame.MAXIMIZED_BOTH);
frame.setUndecorated(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(null);
frame.setCursor(new Cursor(Cursor.HAND_CURSOR));
frame.getContentPane().setBackground(Color.BLACK);
frame.setVisible(true);
}
public void setComponents() {
slider.setBounds(0,640,1000,15);
slider.setBackground(Color.BLACK);
slider.addChangeListener(this);
slider.setValue(0);
playLabel.setBounds(450,665,100,100);
playLabel.addMouseListener(this);
openLabel.setBounds(540,690,60,60);
openLabel.addMouseListener(this);
colorPanel.setBackground(Color.BLACK);
colorPanel.setBounds(0,100,1500,500);
frame.add(openLabel);
frame.add(playLabel);
frame.add(colorPanel);
frame.add(slider);
}
public void mouseClicked(MouseEvent clicked) {
if (clicked.getSource() == openLabel) {
openLabel.setIcon(openImage);
open();
}
else if (clicked.getSource()==playLabel && playStatus != Status.OFF) {
if (playStatus == Status.PAUSE) {
songClip.start();
screenThread.resume();
playStatus=Status.ON;
playLabel.setIcon(pauseImage);
}
else if (playStatus == Status.ON) {
songClip.stop();
screenThread.suspend();
playStatus=Status.PAUSE;
playLabel.setIcon(playImage);
}
else if (playStatus==Status.END) {
songClip.setMicrosecondPosition(0);
slider.setValue(0);
songClip.start();
screenThread.resume();
playStatus = Status.ON;
playLabel.setIcon(pauseImage);
}
}
}
public void stateChanged(ChangeEvent e) {
if (playStatus != Status.OFF) {
JSlider jslider = (JSlider)e.getSource();
int position = jslider.getValue();
songClip.setMicrosecondPosition(position * 1000000);
}
}
public void open() {
JFileChooser chooseSong = new JFileChooser();
chooseSong.setFileSelectionMode(JFileChooser.FILES_ONLY);
chooseSong.setFileFilter(new FileNameExtensionFilter(null, "wav"));
int chooseButton = chooseSong.showOpenDialog(null);
File songPath = chooseSong.getSelectedFile();
if ( (chooseButton!=JFileChooser.CANCEL_OPTION) && (songPath!=null) && (songPath.getName() != null) ) {
try {
playLabel.setIcon(pauseImage);
if (playStatus != Status.OFF)
songClip.close();
AudioInputStream songFile = AudioSystem.getAudioInputStream(songPath);
songClip = AudioSystem.getClip();
songClip.open(songFile);
int clipLength = (int)(songClip.getMicrosecondLength() / 1000000);
slider.setMinimum(0);
slider.setMaximum(clipLength);
songClip.start();
if (playStatus == Status.OFF)
screenThread.start();
else if (playStatus != Status.OFF)
screenThread.resume();
playStatus=Status.ON;
}
catch(Exception exp) {
Toolkit.getDefaultToolkit().beep();
JOptionPane.showMessageDialog(null, String.format("ERROR = %s",exp.getClass()));
System.exit(0);
}
}
}
public void run() {
while (true) {
colorPanel.setBackground(new Color(new Random().nextInt(256), new Random().nextInt(256), new Random().nextInt(256)));
if (songClip.getMicrosecondPosition() == songClip.getMicrosecondLength()) {
screenThread.suspend();
playStatus=Status.END;
playLabel.setIcon(playImage);
}
}
}
}
You are calling screenThread.suspend();
in the block that responds to clicking the play/pause button. Thread methods suspend()
and resume()
are deadlock prone - that is, using them often causes hard-to-diagnose issues like the one you're having.
You need to remove the use of these methods by instead polling a variable, as described on this page .
This method has been deprecated, as it is inherently deadlock-prone.
This is the reason that is given for the deprecation of Thread.stop()
, .suspend()
and .resume()
. As you are using these in your code it could be the problem.
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