Java tutorial
import java.awt.Color; import javax.swing.AbstractButton; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.event.ChangeEvent; import javax.swing.event.ChangeListener; public class Main { public static void main(String[] args) { AbstractButton jb = new JButton("Press Me"); jb.addChangeListener(new ChangeListener() { public void stateChanged(ChangeEvent ev) { System.out.println("ChangeEvent!"); } }); jb.setText("new text"); JFrame f = new JFrame(); f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); f.getContentPane().add(jb); f.pack(); f.setVisible(true); } }