sementara

package javaapplication20;
import java.awt.*;
import javax.swing.*;

class fudc {
        JFrame f;
        JPanel p1, p2, p3, p, p4,p0,pz;
        JTabbedPane tp;
        JScrollPane sp1;
        fudc() {
                f = new JFrame("Fatihul Ulum");
                p = new JPanel(new GridLayout(1, 2));
                p1 = new JPanel(new GridLayout(1, 2));
                p2 = new JPanel(new GridLayout(1, 2));
                p0 = new JPanel(new GridLayout(1, 2));
                pz = new JPanel(new GridLayout(1, 2));
                tp = new JTabbedPane();
 
                final JTextArea area = new JTextArea(1, 2);
                final JScrollPane pane = new JScrollPane(area);
               
                tambah tam = new tambah();
                p1.add(tam);
              
                kurang op = new kurang();
                p2.add(op);
             
                kali d =new kali();
                p.add(d);
             
                bagi ho =new bagi();
                p0.add(ho);

                persamaan per= new persamaan();
                pz.add(per);
               
                pane.setVisible(false);
                f.getContentPane().add(tp);
                tp.addTab("pertambahan", p1);
                tp.addTab("pengurangan", p2);
                tp.addTab("perkalian", p);
                tp.addTab("pembagian", p0);
                tp.addTab("persamaan dua variabel", pz);
                f.setSize(700, 350);
                f.setVisible(true);
        }
        public static void main(String z[]) {
                fudc app = new fudc();
        }
}
//.......................................................................
file kedua :
package javaapplication20;
import java.awt.Color;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;

public class kali extends JPanel {
    JTextField txtawal,txtsani,txthasil;
    public kali(){
        JPanel panel = new JPanel();
        panel.setLayout(new GridLayout(6, 3, 3, 3));
        // membuat Label !!!
        JLabel awal = new JLabel("pertama");
        JLabel sani = new JLabel("kedua:");
        JLabel hasil = new JLabel("hasil");
        JLabel coba = new JLabel("[*].........perkalian.........[*]");
        // membuat JtextField !!!
        txtawal = new JTextField();
        txtsani = new JTextField();
        txthasil = new JTextField();
        // membuat Button !!!
        Icon imgicon = new ImageIcon("/home/boyz/Downloads/1296530999_emblem-OK.png");
        JButton button = new JButton("");
        button.setIcon(imgicon);
        Icon img = new ImageIcon("/home/boyz/Downloads/1296531643_gem_cancel_3.png");
        JButton button1 = new JButton("");
        button1.setIcon(img);
        Icon rst = new ImageIcon("/home/boyz/Downloads/1296531794_Reset.png");
        JButton button2 = new JButton("Reset");
        button2.setIcon(rst);

        panel.add(awal);
        panel.add(txtawal);
        panel.add(sani);
        panel.add(txtsani);
        panel.add(hasil);
        panel.add(txthasil);
        panel.add(button);
        panel.add(button2);
        panel.add(coba);
        panel.add(button1);
        panel.setBackground(Color.LIGHT_GRAY);
        add(panel);
        button1.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent ae) {
                            JDialog.setDefaultLookAndFeelDecorated(true);
                            int response = JOptionPane.showConfirmDialog(null,"apakah anda yakin ingin keluar ?","OOppzz",
                                    JOptionPane.YES_NO_OPTION, JOptionPane.QUESTION_MESSAGE);
                            if (response == JOptionPane.NO_OPTION) {
                                System.out.println("No button clicked");
                            }
                            else if (response == JOptionPane.YES_OPTION)
                            {
                                System.exit(0);
                            }
                            else if (response == JOptionPane.CLOSED_OPTION) {
                            }
            }
        });
        button2.addActionListener(new ActionListener() {
                        public void actionPerformed(ActionEvent ae) {
                                txtawal.setText("");
                                txtsani.setText("");
                                txthasil.setText("");
                        }
                });
        button.addActionListener(new ActionListener() {
           int c;
           String hasil;
           public void actionPerformed(ActionEvent ae) {
               String a = txtawal.getText();
               int aa = Integer.parseInt(a);
               String b= txtsani.getText();
               int bb = Integer.parseInt(b);
               c = aa * bb;
               hasil=Integer.toString(c);
               txthasil.setText(hasil);
           }
        });
    }
}

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