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

public class SApplet extends Applet implements ActionListener {
	TextField input,output;
	Label label1,label2;
	Button b1;
	JLabel lbl;
	int num, sum = 0;
	public void init(){
		label1 = new Label("please enter number : ");
		add(label1);
		label1.setBackground(Color.yellow);
		label1.setForeground(Color.magenta);
		input = new TextField(5);
		add(input);
		label2 = new Label("Sum : ");
		add(label2);
		label2.setBackground(Color.yellow);
		label2.setForeground(Color.magenta);
		output = new TextField(20);
		add(output);
//		input.addActionListener( this );
		b1 = new Button("Add");
		add(b1);
		b1.addActionListener(this);
		lbl = new JLabel("This is the Swing Applet Example.          ");
		add(lbl);
		setBackground(Color.yellow);

//		output.addActionListener( this );
	}
	public void actionPerformed(ActionEvent ae){
		try{
//			num = Integer.parseInt(ae.getActionCommand());
			num = Integer.parseInt(input.getText());
			sum = sum+num;
			input.setText("");
			output.setText(Integer.toString(sum));
			lbl.setForeground(Color.blue);
			lbl.setText("Output of the second Text Box : " + output.getText());
		}
		catch(NumberFormatException e){
			lbl.setForeground(Color.red);
			lbl.setText("Invalid Entry!");
		}
	}
}