How to add action listener to JButton in Java

The following is an example to add action listener to Button:

Example

package my; import java.awt.*; import java.awt.event.*; import javax.swing.*; public class SwingDemo {    private JFrame frame;    private JLabel headerLabel;    private JLabel statusLabel;    private JPanel controlPanel;    public SwingDemo(){       prepareGUI();    }    public static void main(String[] args){       SwingDemo swingControlDemo = new SwingDemo();       swingControlDemo.showButtonDemo();    }    private void prepareGUI(){       frame = new JFrame("Java Swing");       frame.setSize(500,500);       frame.setLayout(new GridLayout(3, 1));       frame.addWindowListener(new WindowAdapter() {          public void windowClosing(WindowEvent windowEvent){             System.exit(0);          }       });       headerLabel = new JLabel("", JLabel.CENTER);       statusLabel = new JLabel("",JLabel.CENTER);       statusLabel.setSize(350,100);       controlPanel = new JPanel();       controlPanel.setLayout(new FlowLayout());       frame.add(headerLabel);       frame.add(controlPanel);       frame.add(statusLabel);       frame.setVisible(true);    }    private void showButtonDemo(){       headerLabel.setText("Button Demo");       JButton okButton = new JButton("OK");       okButton.addActionListener(new ActionListener() {          public void actionPerformed(ActionEvent e) {             statusLabel.setText("Ok Button is clicked here");          }       });       controlPanel.add(okButton);       frame.setVisible(true);    } }

Output

Now, after clicking the OK button above, the following is visible: