mau nanya program swing dan awt pada java ngga jalan nh

[Badguy13]

permisi master2 programing sekalian

saya bingung program saya kenapa ngga jalan2 yaa



INI PROGRAMNYA



import javax.swing.JFrame;

import javax.swing.JButton;

import javax.swing.JLabel;

import javax.swing.JTextField;

import javax.swing.JCheckBox;

import javax.swing.JComboBox;

import java.awt.Font;

import java.awt.Color;

import java.awt.event.ActionListener;

import java.awt.event.ActionEvent;

import java.awt.event.ItemListener;

import java.awt.event.ItemEvent;



class tampilan extends JFrame implements ActionListener {

private int ht, sub, jum;

private double disc, total;

private String [] item = {"","Jakarta","Cirebon","Tasikmalaya"};

private JComboBox tuj = new JComboBox(item);

private JLabel judul = new JLabel("Program Travel Bintang Kejora");

private JLabel nama = new JLabel("nama");

private JLabel tujuan = new JLabel("tujuan");

private JLabel jumlah = new JLabel("jumlah");

private JLabel member = new JLabel("member");

private JCheckBox cb = new JCheckBox ("ya");

private JLabel harga = new JLabel ("harga tiket");

private JLabel sub_t = new JLabel ("sub total");

private JLabel diskon = new JLabel ("diskon");

private JLabel t_harga = new JLabel ("Total harga");

private JTextField txtnama = new JTextField();

private JTextField txtjumlah = new JTextField();

private JTextField txtharga = new JTextField();

private JTextField txtsub = new JTextField();

private JTextField txtdiskon = new JTextField();

private JTextField txttotal = new JTextField();

private JButton hitung = new JButton ("hitung");

private JButton ulangi = new JButton ("ulangi");



tampilan() {

super("program travel ini dibuat oleh GHES");

setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

setLocation(100,100);

setSize(495,250);

setLayout(null);

add(judul);

add(nama);

add(txtnama);

add(tujuan);

add(tuj);

add(jumlah);

add(txtjumlah);

add(member);

add(cb);

add(harga);

add(txtharga);

add(sub_t);

add(txtsub);

add(diskon);

add(txtdiskon);

add(t_harga);

add(txttotal);

add(hitung);

add(ulangi);

judul.setFont(new Font("times new roman",Font .BOLD,20));

judul.setBounds(10,10,300,20);

nama.setBounds(10,50,100,20);

txtnama.setBounds(120,50,100,20);

tujuan.setBounds(10,100,100,20);

tuj.setBounds(120,75,100,20);

jumlah.setBounds(10,100,100,20);

txtjumlah.setBounds(120,100,100,20);

member.setBounds(10,125,100,20);

cb.setBounds(115,125,100,20);

harga.setBounds(260,50,100,20);

txtharga.setBounds(370,50,100,20);

sub_t.setBounds(260,75,100,20);

txtsub.setBounds(370,75,100,20);

diskon.setBounds(260,100,100,20);

txtdiskon.setBounds(370,100,100,20);

t_harga.setBounds(260,125,100,20);

txttotal.setBounds(370,125,100,20);

hitung.setBounds(130,175,100,20);

ulangi.setBounds(250,175,100,20);

}



public void actionperformed(ActionEvent e) {

String item = (String)tuj.getSelectedItem();

if (item.equals("Jakarta")){

ht = 100000;

}

else if (item.equals("Cirebon")) {

ht = 150000;

}

else if (item.equals("Tasikmalaya")) {

ht = 200000;

}

else {

ht = 0;

}



Object obj = e.getSource();



if (obj == hitung) {

jum = Integer.parseInt(txtjumlah.getText());

sub = jum * ht;

if (cb.isSelected()) {

disc = 0.10 * sub;

}

else {

disc = 0.0 * sub;

}

txtharga.setText("Rp. "+ht);

txtsub.setText("Rp. "+sub);

txtdiskon.setText("Rp. "+disc);

txttotal.setText("Rp. "+total);

}

if (obj == ulangi) {

txtnama.setText("");

txtjumlah.setText("");

txtharga.setText("");

txtsub.setText("");

txtdiskon.setText("");

txttotal.setText("");

}

}

}



public class travel{

public static void main(String args []) {

new tampilan();

}

}







berikut ini errornya gan







makasih banyak jika ada yg ngasih tau sebesarnya

semoga hidup ente makin sukses



thanks