1  import java.awt.*;

  2  import java.awt.event.*;

  3  import javax.swing.*;

  4  

  5  public class ActionTester

  6  {

  7     public static void main(String[] args)

  8     {

  9        JFrame frame = new JFrame();

 10  

 11        final int FIELD_WIDTH = 20;

 12        final JTextField textField = new JTextField(FIELD_WIDTH);

 13        textField.setText("Click a button!");

 14  

 15        JButton helloButton = new JButton("Say Hello");

 16  

 17        helloButton.addActionListener(event ->

 18           textField.setText("Hello, World!"));

 19  

 20        JButton goodbyeButton = new JButton("Say Goodbye");

 21  

 22        goodbyeButton.addActionListener(event ->

 23           textField.setText("Goodbye, World!"));

 24  

 25        frame.setLayout(new FlowLayout());

 26  

 27        frame.add(helloButton);

 28        frame.add(goodbyeButton);

 29        frame.add(textField);

 30  

 31        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

 32        frame.pack();

 33        frame.setVisible(true);

 34     }

 35  }