calculator.java

package AdvJava;

import java.awt.Button;
import java.awt.Frame;
import java.awt.Label;
import java.awt.TextField;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class calc implements ActionListener {

    Frame f = new Frame();
    Label l1 = new Label("First Number");
    Label l2 = new Label("Second Number");
    Label l3 = new Label("Result");

    TextField t1 = new TextField();
    TextField t2 = new TextField();
    TextField t3 = new TextField();

    Button b1 = new Button("Add");
    Button b2 = new Button("Sub");
    Button b3 = new Button("Mul");
    Button b4 = new Button("Div");
    Button b5 = new Button("Cancel");

    calc() {

        l1.setBounds(50, 100, 100, 20);
        l2.setBounds(50, 140, 100, 20);
        l3.setBounds(50, 180, 100, 20);

        t1.setBounds(200, 100, 100, 20);
        t2.setBounds(200, 140, 100, 20);
        t3.setBounds(200, 180, 100, 20);

        b1.setBounds(50, 250, 50, 20);
        b2.setBounds(110, 250, 50, 20);
        b3.setBounds(170, 250, 50, 20);
        b4.setBounds(230, 250, 50, 20);
        b5.setBounds(290, 250, 50, 20);

        f.add(l1);
        f.add(l2);
        f.add(l3);

        f.add(t1);
        f.add(t2);
        f.add(t3);

        f.add(b1);
        f.add(b2);
        f.add(b3);
        f.add(b4);
        f.add(b5);

        b1.addActionListener(this);
        b2.addActionListener(this);
        b3.addActionListener(this);
        b4.addActionListener(this);
        b5.addActionListener(this);

        f.setLayout(null);
        f.setVisible(true);
        f.setSize(400, 350);
        f.setLocation(500, 200);
    }

    public void actionPerformed(ActionEvent e) {
        int n1 = Integer.parseInt(t1.getText());
        int n2 = Integer.parseInt(t2.getText());

        if (e.getSource() == b1) {
            t3.setText(String.valueOf(n1 + n2));
        }
        if (e.getSource() == b2) {
            t3.setText(String.valueOf(n1 - n2));
        }
        if (e.getSource() == b3) {
            t3.setText(String.valueOf(n1 * n2));
        }
        if (e.getSource() == b4) {
            t3.setText(String.valueOf(n1 / n2));
        }
        if (e.getSource() == b5) {
            System.exit(0);
        }
    }

    public static void main(String[] args) {
        new calc();

    }

}