Create JFrame window with window close event

This is an example on how to create a JFrame window with window close event. Pairing a window with a closing event is a very common practice in most GUI applications. When the user closes a window, it usually means that you have to release several resources or event exit the application.

The basic steps to create a JFrame with a window closing event is:

• Create a class that extends JFrame.
• Create a class that extends WindowAdapter.
• Override the windowClosing method. Now every time the window closes, this method will fire up.

Let’s take a look at the code snippets that follow:

package com.javacodegeeks.snippets.desktop;

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

import javax.swing.JFrame;

public class CreateJFrameWindowWithWindowCloseEvent  extends JFrame {

	private static final long serialVersionUID = 1L;

	public CreateJFrameWindowWithWindowCloseEvent() {
		setTitle("Simple Frame");

  setSize(200, 200);
		addWindowListener(new CustomWindowAdapter(this));
	}

	private static void createAndShowGUI() {

  //Create and set up the window.

  JFrame frame = new CreateJFrameWindowWithWindowCloseEvent();

  //Display the window.

  frame.setVisible(true);

    }

	public static void main(String[] args) {

  //Schedule a job for the event-dispatching thread:

  //creating and showing this application's GUI.

  javax.swing.SwingUtilities.invokeLater(new Runnable() {

public void run() {

    createAndShowGUI(); 

}

  });
    }

	class CustomWindowAdapter extends WindowAdapter {

		CreateJFrameWindowWithWindowCloseEvent window = null;

		CustomWindowAdapter(CreateJFrameWindowWithWindowCloseEvent window) {
			this.window = window;
		}

		// implement windowClosing method
		public void windowClosing(WindowEvent e) {
			// exit the application when window's close button is clicked
			System.exit(0);
		}
	}

}

 
This was an example on how to create a JFrame with a window closing event.