Everything in one place - Applet Life Cycle, Parameter Passing ,Drawing, ButtonEvent, MouseEvent & DialogBox

AppletDemo.java

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

/*
 <applet code="AppletDemo" width="320" height="320">
    <param name="myName" value="ritwick dey"/>
 </applet>
 */

public class AppletDemo extends Applet implements ActionListener, MouseMotionListener
{
    public void init()
    {
        System.out.println("Applet - init");

        Button redBtn = new Button("Red");
        Button blueBtn = new Button("Blue");
        Button greenBtn = new Button("Green");

        add(redBtn);
        add(blueBtn);
        add(greenBtn);

        redBtn.addActionListener(this);
        blueBtn.addActionListener(this);
        greenBtn.addActionListener(this);

        addMouseMotionListener(this);

    }
    public void start()
    {
        System.out.println("Applet - start");

        int num1 = Integer.parseInt(JOptionPane.showInputDialog(null, "Enter 1st Num: "));
        int num2 = Integer.parseInt(JOptionPane.showInputDialog(null, "Enter 2st Num: "));
        JOptionPane.showMessageDialog(null,"Sum = " + (num1+num2));
    }
    public void stop()
    {
        System.out.println("Applet - stop");
    }
    public void destroy()
    {
        System.out.println("Applet - destroy");
    }

    public void paint(Graphics g)
    {
        //parameter passing
        String myName = getParameter("myName");
        if(myName == null) 
            myName = "no name";
        
        //drawing
        g.drawString(myName, 50,50);
        g.drawRect(70,70,130,130);
        g.drawLine(70,70,130,130);
        g.drawOval(70,70,130,130);
    }

    //button event
    public void actionPerformed(ActionEvent ae)
    {
        switch(ae.getActionCommand())
        {
            case "Red":
                setBackground(Color.red);
                break;
            case "Green":
                setBackground(Color.green);
                break;
            case "Blue":
                setBackground(Color.blue);
                break;
        }

    }

    public void mouseMoved(MouseEvent me) 
    {
        System.out.println("Mouse is moving...");
    }

    public void mouseDragged(MouseEvent me)
    {
        System.out.println("Mouse is dragging...");
    }
}