TwoButtons.java

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

public class TwoButtons {
 JFrame frame;
 JLabel label;

 public static void main (String[] args) {
 TwoButtons gui = new TwoButtons();
 gui.go();
 }

 public void go() {
 frame = new JFrame();
 frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

 JButton labelButton = new JButton("Change Label");
 labelButton.addActionListener(new LabelButtonListener());

 JButton colorButton = new JButton("Change Circle");
 colorButton.addActionListener(new ColorButtonListener());

 label = new JLabel("I'm a label");
 MyDrawPanel drawPanel = new MyDrawPanel();

 frame.getContentPane().add(BorderLayout.SOUTH, colorButton);
 frame.getContentPane().add(BorderLayout.CENTER, drawPanel);
 frame.getContentPane().add(BorderLayout.EAST, labelButton);
 frame.getContentPane().add(BorderLayout.WEST, label);

 frame.setSize(420,300);
 frame.setVisible(true);
 }

 class LabelButtonListener implements ActionListener {
 public void actionPerformed(ActionEvent event) {
 label.setText("Ouch!");
 }
 } // close inner class

 class ColorButtonListener implements ActionListener {
 public void actionPerformed(ActionEvent event) {
 frame.repaint();
 }
 } // close inner class

}

class MyDrawPanel extends JPanel {

 public void paintComponent(Graphics g) {

 g.fillRect(0,0,this.getWidth(), this.getHeight());

 // make random colors to fill with
 int red = (int) (Math.random() * 255);
 int green = (int) (Math.random() * 255);
 int blue = (int) (Math.random() * 255);

 Color randomColor = new Color(red, green, blue);
 g.setColor(randomColor);
 g.fillOval(70,70,100,100);
 }
}