SQL with Manoj

Q53: Java Program to write an applet which have three text fields, first two accepts input from user and third one shows the result. It should have four buttons indicating operation add, subtract, multiply and divide, pressing the button should put the result in the third text field.

import java.awt.*;
import java.awt.event.*;
import java.applet.*;
import java.awt.TextField.*;

public class Ap_Calc extends Applet implements ActionListener{
	TextField one, two, res;
	Button add, sub, mul, div;

	public void init(){
		Label l1 = new Label("First Number:   ",Label.RIGHT);
		Label l2 = new Label("Second Number:  ",Label.RIGHT);
		Label l3 = new Label("Result:         ",Label.RIGHT);
 
		one = new TextField(5);
		two = new TextField(5);
		res = new TextField(7);

		add = new Button("Add");
		sub = new Button("Substract");
		mul = new Button("Multiply");
		div = new Button("Divide");

		add(l1);
		add(one);
		add(l2);
		add(two);
		add(l3);
		add(res);
	
		add(add);
		add(sub);
		add(div);
		add(mul);

		one.addActionListener(this);
		two.addActionListener(this);
		res.addActionListener(this);
		add.addActionListener(this);
		sub.addActionListener(this);
		div.addActionListener(this);
		mul.addActionListener(this);		
	}

	public void actionPerformed(ActionEvent ae){
		String str = ae.getActionCommand();
		float b1, b2, b3 = 0;
		String msg;
		
		b1 = Float.parseFloat(one.getText());
		b2 = Float.parseFloat(two.getText());
		
		if(str.equals("Add"))
			b3 = b1 + b2;
		if(str.equals("Substract"))
			b3 = b1 - b2;
		if(str.equals("Divide"))
			b3 = b1 / b2;
		if(str.equals("Multiply"))
			b3 = b1 * b2;
		msg = String.valueOf(b3);
		res.setText(msg);	
		repaint();
	}
	
	public void paint(Graphics g){
	}
}

… from College notes (BCA/MCA assignments):