Program Java Sederhana (TextField)

import java.awt.*;

import java.awt.event.*;

import javax.swing.*;

class DemoTextField implements ActionListener {

public JLabel label1, label2, label3;

public JTextField textField1, textField2, textField3;

public JButton button1, button2, button3, button4;

public DemoTextField(){

label1 = new JLabel("Nilai A");

label1.setLocation(10,10);

label1.setSize(label1.getPreferredSize());

textField1 = new JTextField(20);

textField1.setLocation(10,25);

textField1.setSize(textField1.getPreferredSize());

label2 = new JLabel("Nilai B");

label2.setLocation(10,45);

label2.setSize(label2.getPreferredSize());

textField2 = new JTextField(20);

textField2.setLocation(10,60);

textField2.setSize(textField2.getPreferredSize());

label3 = new JLabel("Hasil Perhitungan Antara A Dan B");

label3.setLocation(10,90);

label3.setSize(label3.getPreferredSize());

textField3 = new JTextField(20);

textField3.setLocation(10,105);

textField3.setSize(textField3.getPreferredSize());

textField3.setEditable(false);

button1 = new JButton("Tambah");

button1.setLocation(245, 10);

button1.setSize(button1.getPreferredSize());

button1.addActionListener(this);

button1.setMnemonic('T');

button2 = new JButton("Kurang");

button2.setLocation(245, 40);

button2.setSize(button2.getPreferredSize());

button2.addActionListener(this);

button2.setMnemonic('u');

button3 = new JButton("Kali");

button3.setLocation(245, 70);

button3.setSize(button3.getPreferredSize());

button3.addActionListener(this);

button3.setMnemonic('K');

button4 = new JButton("Bagi");

button4.setLocation(245, 100);

button4.setSize(button4.getPreferredSize());

button4.addActionListener(this);

button4.setMnemonic('B');

}

public void createAndShowGUI(){

JFrame.setDefaultLookAndFeelDecorated(true);

JFrame frame = new JFrame("Contoh JTextField");

frame.setLayout(null);

frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

frame.getContentPane().add(label1);

frame.getContentPane().add(textField1);

frame.getContentPane().add(label2);

frame.getContentPane().add(textField2);

frame.getContentPane().add(label3);

frame.getContentPane().add(textField3);

frame.getContentPane().add(button1);

frame.getContentPane().add(button2);

frame.getContentPane().add(button3);

frame.getContentPane().add(button4);

frame.setBounds(0,0, 350, 200);

frame.setLocationRelativeTo(null);

frame.setVisible(true);

}

public void actionPerformed(ActionEvent event) {

double a=0.0, b=0.0, c=0.0;

try {

a=Double.parseDouble(textField1.getText());

b=Double.parseDouble(textField2.getText());

} catch (NumberFormatException nfe) {

nfe.printStackTrace();

}

JButton btn = (JButton) event.getSource();

if(btn==button1){

c=a+b;

} else if(btn==button2){

c=a-b;

} else if(btn==button3){

c=a*b;

} else {

c=a/b;

}

textField3.setText(new String().valueOf(c));

}

public static void main(String[]args){

javax.swing.SwingUtilities.invokeLater(new Runnable(){

public void run(){

DemoTextField app = new DemoTextField();

app.createAndShowGUI();

}

});

}

}

HASILNYA :