Closing a Frame in Java AWT

To close a frame in AWT, you need to define a WindowAdapter object that will call the methods you want when the close button will be clicked. If it often beneficial to declare this new class as a nested type of the frame, since it could access the frame's methods and members.

To practically close the window, you must first make it invisible to the user and then free all the resources it occupies.

import java.awt.Frame;
import java.awt.Label;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

public class MyFrame extends Frame 
{
    public class CloseWindowEvent extends WindowAdapter 
    {        
        public void windowClosing(WindowEvent we)
        {
            //Make the frame invisible
            MyFrame.this.setVisible(false);
            //Free all resources
            MyFrame.this.dispose();
            //If you also want to close the program,uncomment bellow
            //System.exit(0);
        }
    }
    
    public MyFrame(String title)
    {
        super(title);
        this.add(new Label("Click X to Close"));
        //Adds the listener to the class
        this.addWindowListener(new CloseWindowEvent());
        this.pack();
    }
}

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