Using Threads in Swing?

Question

Java

Now I'm trying to deal with multithreading in swing.

For example, there is a window in which there is a button, by clicking on which some long-term action-A is performed. In order for the GUI not to freeze, I decided to run the same action-A in a new thread.

It looks like this:

The code

package swing.aug17_2;

import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JFrame;

public class SwingApp2 {

  private JFrame frame;
  private JButton btn;
  
  public static void main(String[] args) {
    EventQueue.invokeLater(new Runnable(){
      public void run(){
        try {
          SwingApp2 app = new SwingApp2();
          app.frame.setVisible(true);
        } catch (Exception e){
          e.printStackTrace();
        }
      }
    });
  }
  
  public SwingApp2(){
    initialize();
  }

  private void initialize() {
    frame = new JFrame();
    frame.setTitle("Hello Swing");
    frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
    frame.setPreferredSize(new Dimension(300, 80));
    frame.setSize(300, 80);
    frame.setLocationRelativeTo(null);
    frame.setIconImage(Toolkit.getDefaultToolkit().getImage(SwingApp2.class.getResource("/icon.png")));
    frame.getContentPane().setLayout(new BorderLayout());
    
    btn = new JButton("PUSH");
    btn.addActionListener(new ActionListener() {
      
      public void actionPerformed(ActionEvent e) {
        Thread thr = new Thread(){
          @Override
          public void run(){
            try {
              Thread.sleep(2000);
              System.out.println("Done");
            } catch (InterruptedException e) {
              e.printStackTrace();
            }
            
          }
        };
        thr.start();
        
      }
    });
    frame.add(btn, BorderLayout.CENTER);		
  }
}

There are doubts about calling action-A in a new thread. Is it correct to call in this way? If not, please suggest the right way.
Thank you.

Answer 1

All OK, do not hesitate.