Program Kalkulator Sederhana

Program: Kalkulator.java
import javax.swing.*;
import java.awt.GridLayout;
import java.awt.BorderLayout;
public class Kalkulator {
JPanel panelJendela = new JPanel();
JTextField fieldHasil = new JTextField(20);
JLabel labelNama = new JLabel(“Created by …..”);
JButton button0 = new JButton(“0″);
JButton button1 = new JButton(“1″);
JButton button2 = new JButton(“2″);
JButton button3 = new JButton(“3″);
JButton button4 = new JButton(“4″);
JButton button5 = new JButton(“5″);
JButton button6 = new JButton(“6″);
JButton button7 = new JButton(“7″);
JButton button8 = new JButton(“8″);
JButton button9 = new JButton(“9″);
JButton buttonTambah = new JButton(“+”);
JButton buttonKurang = new JButton(“-”);
JButton buttonKali = new JButton(“x”);
JButton buttonBagi = new JButton(“/”);
JButton buttonKoma = new JButton(“.”);
JButton buttonSamadengan = new JButton(“=”);
JButton buttonHapus = new JButton(“C”);
JPanel panel1 = new JPanel();
JPanel panel2 = new JPanel();
Kalkulator() {
BorderLayout bl = new BorderLayout();
panelJendela.setLayout(bl);
panelJendela.add(“North”, fieldHasil);
GridLayout gl = new GridLayout(5,3);
panel1.setLayout(gl);
panel1.add(button1);
panel1.add(button2);
panel1.add(button3);
panel1.add(button4);
panel1.add(button5);
panel1.add(button6);
panel1.add(button7);
panel1.add(button8);
panel1.add(button9);
panel1.add(button0);
panel1.add(buttonKoma);

panel1.add(buttonSamadengan);
panelJendela.add(“Center”, panel1);
GridLayout gl2 = new GridLayout(5,1);
panel2.setLayout(gl2);
panel2.add(buttonTambah);
panel2.add(buttonKurang);
panel2.add(buttonKali);
panel2.add(buttonBagi);
panel2.add(buttonHapus);
panelJendela.add(“East”, panel2);
panelJendela.add(“South”, labelNama);
JFrame jendela = new JFrame(“kalkulator”);
jendela.setContentPane(panelJendela);
jendela.pack();
jendela.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
jendela.setVisible(true);
mesin4 mesin = new mesin4(this);
button0.addActionListener(mesin);
button1.addActionListener(mesin);
button2.addActionListener(mesin);
button3.addActionListener(mesin);
button4.addActionListener(mesin);
button5.addActionListener(mesin);
button6.addActionListener(mesin);
button7.addActionListener(mesin);
button8.addActionListener(mesin);
button9.addActionListener(mesin);
buttonKoma.addActionListener(mesin);
buttonTambah.addActionListener(mesin);
buttonKali.addActionListener(mesin);
buttonKurang.addActionListener(mesin);
buttonBagi.addActionListener(mesin);
buttonSamadengan.addActionListener(mesin);
}
public static void main(String[] args) {
Kalkulator kalkul = new Kalkulator();
}
}
Nama program: mesin1.java
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;
public class mesin1 implements ActionListener {
public void actionPerformed(ActionEvent kejadian) {
JOptionPane.showMessageDialog(null, “ada tombol yang diklik…”);
}
}
Nama program: mesin2.java
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;
public class mesin2 implements ActionListener {
public void actionPerformed(ActionEvent kejadian) {
JButton tombolDiklik = (JButton) kejadian.getSource();
String labelTombolDiklik = tombolDiklik.getText();
JOptionPane.showMessageDialog(null, “anda mengklik ” + labelTombolDiklik);
}
}
Nama program: mesin3.java
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;
public class mesin3 implements ActionListener {
Kalkulator induk;
mesin3(Kalkulator induk) {
this.induk = induk;
}
public void actionPerformed(ActionEvent kejadian) {
JButton tombolDiklik = (JButton) kejadian.getSource();
String tampilanBaru = tombolDiklik.getText();
String tampilanLama = induk.fieldHasil.getText();
induk.fieldHasil.setText(tampilanLama + tampilanBaru);
}
}
Nama program: mesin4.java
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import javax.swing.*;
public class mesin4 implements ActionListener {
Kalkulator induk;
char operatorAritmatika = ‘ ‘;
double hasilSekarang = 0;
mesin4(Kalkulator induk) {
this.induk = induk;
}
public void actionPerformed(ActionEvent kejadian) {
JButton tombolDiklik = (JButton) kejadian.getSource();
String tampilDiFieldHasil = induk.fieldHasil.getText();
double nilaiDitampilkan = 0;
if(!”".equals(tampilDiFieldHasil)) {
nilaiDitampilkan = Double.parseDouble(tampilDiFieldHasil);
}
Object sumber = kejadian.getSource();
if(sumber == induk.buttonTambah) {
operatorAritmatika = ‘+’;
hasilSekarang = nilaiDitampilkan;
induk.fieldHasil.setText(“”);
} else if(sumber == induk.buttonKurang) {
operatorAritmatika = ‘-’;
hasilSekarang = nilaiDitampilkan;
induk.fieldHasil.setText(“”);
} else if(sumber == induk.buttonBagi) {
operatorAritmatika = ‘/’;
hasilSekarang = nilaiDitampilkan;
induk.fieldHasil.setText(“”);
} else if(sumber == induk.buttonKali) {
operatorAritmatika = ‘*’;
hasilSekarang = nilaiDitampilkan;
induk.fieldHasil.setText(“”);
} else if(sumber == induk.buttonSamadengan) {
if(operatorAritmatika==’+') {
hasilSekarang += nilaiDitampilkan;
induk.fieldHasil.setText(“”+hasilSekarang);
} else if(operatorAritmatika==’-') {
hasilSekarang -= nilaiDitampilkan;
induk.fieldHasil.setText(“”+hasilSekarang);
} else if(operatorAritmatika==’/') {
hasilSekarang /= nilaiDitampilkan;
induk.fieldHasil.setText(“”+hasilSekarang);
} else if(operatorAritmatika==’*') {
hasilSekarang *= nilaiDitampilkan;
induk.fieldHasil.setText(“”+hasilSekarang);
}
} else {
String labelButtonDiklik = tombolDiklik.getText();
induk.fieldHasil.setText(tampilDiFieldHasil + labelButtonDiklik);
}
}
}