Action events occur when a user completes an action using one of the following components: JButton, JCheckBox, JComboBox, JTextField, or JRadioButton.

A class must implement ActionListener interface in order to handle those events. The actionPerformed(ActionEvent) method is the only method of the ActionListener interface.

The following example shows how to use action events in Swing:

 import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

public class SwingApplication implements ActionListener {
    
    private static String labelPrefix = "Number of button clicks: ";
    private int numClicks = 0;
    final JLabel label = new JLabel(labelPrefix + "0    ");
    
    public Component createComponents() {
        JButton button = new JButton("I'm a Swing button!");
        button.setMnemonic(KeyEvent.VK_I);
        button.addActionListener(this);
        label.setLabelFor(button);
        
        /*
         * An easy way to put space between a top-level container
         * and its contents is to put the contents in a JPanel
         * that has an "empty" border.
         */
        JPanel pane = new JPanel(new GridLayout(0, 1));
        pane.add(button);
        pane.add(label);
        pane.setBorder(BorderFactory.createEmptyBorder(
                30, //top
                30, //left
                10, //bottom
                30) //right
                );
        
        return pane;
    }
    
    public void actionPerformed(ActionEvent e) {
        numClicks++;
        label.setText(labelPrefix + numClicks);
    }
    
    
    /**
     * Create the GUI and show it.  For thread safety,
     * this method should be invoked from the
     * event-dispatching thread.
     */
    private static void createAndShowGUI() {
        
        //Make sure we have nice window decorations.
        JFrame.setDefaultLookAndFeelDecorated(true);
        
        //Create and set up the window.
        JFrame frame = new JFrame("SwingApplication");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        
        SwingApplication app = new SwingApplication();
        Component contents = app.createComponents();
        frame.getContentPane().add(contents, BorderLayout.CENTER);
        
        //Display the window.
        frame.pack();
        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();
            }
        });
    }
}