Java Applet to Draw Circle or Rectangle

try something like this

/*
 * Assignment2.java
 *
 * Created on 15 December 2008, 18:01
 *
 * To change this template, choose Tools | Template Manager
 * and open the template in the editor.
 */

package pkgAssignment2;

import java.awt.Button;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Label;
import java.awt.Panel;
import java.awt.TextField;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

/**
 *
 * @author MOR08195294
 */
public class Assignment2 extends java.applet.Applet implements ActionListener
{

      Font f = new Font("Timesroman", Font.PLAIN, 20);

      Font f2 = new Font("Arial", Font.ITALIC, 14);

      Label displayLabel, enterLabel;

      TextField displayBox, enterBox;
      TextField widthField = new TextField();
      TextField heightField = new TextField();
      
      Panel circle = new Panel();
      Panel rectangle = new Panel();
      
      Button drawCircle = new Button("Draw A Circle");

      Button drawRectangle = new Button("Draw A Rectangle");

      boolean isCircle = false, isRectangle = false;

      String displayString, inputString;

      /**
       * Initialization method that will be called after the applet is loaded into
       * the browser.
       */
      public void init()
      {

            add(drawCircle);
            add(drawRectangle);
            drawCircle.addActionListener(this);
            drawRectangle.addActionListener(this);
            enterLabel = new Label("Enter");
            enterBox = new TextField(12);
            
            circle.add(enterLabel);
            circle.add(enterBox);
            
            rectangle.add(widthField);
            rectangle.add(heightField);
      }

      // event-handlmg code
      public void actionPerformed(ActionEvent e)
      {
            if (e.getSource() == drawCircle)
            {
                  isCircle = true;
                  isRectangle = false;
                  remove(rectangle);
                  add(circle);
                  invalidate();
                  validate();
            }
            if (e.getSource() == drawRectangle)
            {
                  isCircle = false;
                  isRectangle = true;
                  remove(circle);
                  add(rectangle);
                  invalidate();
                  validate();
            }
      }

      // TODO overwrite start(), stop() and destroy() methods
      public void paint(Graphics gscreen)
      {
            gscreen.setColor(Color.red);
            if (isCircle)
            {
                  gscreen.drawString("Display Box for Circle Radius", 30, 45);
                  gscreen.drawOval(85, 45, 75, 75);
            } else if (isRectangle)
            {
                  gscreen.drawString("Display Box for Rectangle Radius", 30, 45);
            }
      }
}