import javax.swing.*;
import java.applet.*;
import java.awt.*;
import java.util.*;
import java.text.*;
import java.awt.event.*;

public class RC extends JFrame implements ActionListener{
    JTextField text,text1,text2,text3,text4,text5,text6,text7; 
    JLabel label1,label2,label3,label4,label5,label6,label7,label8,label9;
    JLabel lab;
    JButton b1,b2; 
    JComboBox combo;
    DecimalFormat df = new DecimalFormat("$##.##");
    public RC(){
        setLayout(null);
        lab=new JLabel("Welcome to Rental Car System");
lab.setBounds(100,20,200,20);
add(lab);

label1 = new JLabel("Select Type of Car: ");
label1.setBounds(20,50,180,20);
add(label1);
combo=new JComboBox();
combo.addItem("--Select--");
combo.addItem("Honda City");
combo.addItem("Toyota Vios");
combo.addItem("Nissan Latio");
combo.addItem("Proton Iswara");
combo.addItem("Proton Waja");
combo.addItem("Perodua Myvi");
combo.addItem("Toyota Avenza");
combo.addItem("Honda Stream");
combo.addItem("Nissan Grand Livina");
combo.addItem("Perodua Alza");
combo.addItem("Proton Exora");
combo.setBounds(200,50,120,20);
add(combo);
label2 = new JLabel("Enter number of days: ");
label2.setBounds(20,80,180,20);
add(label2);

text = new JTextField(5);
text.setBounds(200,80,100,20);
add(text);

b1 = new JButton("Submit");
b1.setBounds(200,140,100,20);
add(b1);
b1.addActionListener(this);

label3=new JLabel("Enter Customer Name: ");
label3.setBounds(20,60,180,20);
add(label3);

text1=new JTextField(10);
text1.setBounds(230,60,150,20);
add(text1);

label4=new JLabel("Enter IC Number: ");
label4.setBounds(20,90,180,20);
add(label4);

text2=new JTextField(10);
text2.setBounds(230,90,150,20);
add(text2);

label5=new JLabel("Enter Age: ");
label5.setBounds(20,120,180,20);
add(label5);

text3=new JTextField(10);
text3.setBounds(230,120,150,20);
add(text3);

label6=new JLabel("Enter Mobile Number: ");
label6.setBounds(20,150,180,20);
add(label6);

text4=new JTextField(10);
text4.setBounds(230,150,150,20);
add(text4);
label7=new JLabel("Enter  E-Mail Address: ");
label7.setBounds(20,180,180,20);
add(label7);

text5=new JTextField(10);
text5.setBounds(230,180,150,20);
add(text5);

label8=new JLabel("Enter  16 Digit of Credit Card Number: ");
label8.setBounds(20,210,210,20);
add(label8);

text6=new JTextField(10);
text6.setBounds(230,210,150,20);
add(text6);

label9=new JLabel("Enter Pin Code of Credit Card: ");
label9.setBounds(20,240,180,20);
add(label9);

text7=new JTextField(10);
text7.setBounds(230,240,150,20);
add(text7);

continue..

    b2=new JButton("Submit");
b2.setBounds(230,270,100,20);
add(b2);
label3.setVisible(false);
label4.setVisible(false);
label5.setVisible(false);
label6.setVisible(false);
label7.setVisible(false);
label8.setVisible(false);
label9.setVisible(false);
text1.setVisible(false);
text2.setVisible(false);
text3.setVisible(false);
text4.setVisible(false);
text5.setVisible(false);
text6.setVisible(false);
text7.setVisible(false);
b2.setVisible(false);
setVisible(true);
setSize(1024,760);
 }
     public void actionPerformed(ActionEvent ae){
String value=combo.getSelectedItem().toString();
int day=Integer.parseInt(text.getText());
if(value.equals("Honda City")){
    if(day>0){

final double amount=(day-0)*60.00 + 100.00;
JOptionPane.showMessageDialog(null,"Vehicle type= Honda City \n" + " Deposit= Rm100 \n " + " Daily Rate= 60 \n" + "days= " + day+"\n\n"+"Rental Total Charges= "+df.format(amount));
String st=JOptionPane.showInputDialog(null,"Do you want to continue next Process?( y/n ): ");
if(st.equals("y")){
    label1.setVisible(false);
    label2.setVisible(false);
    text.setVisible(false);
    combo.setVisible(false);
    b1.setVisible(false);
    b2.setVisible(true);
    label3.setVisible(true);
    label4.setVisible(true);
    label5.setVisible(true); 
    label6.setVisible(true); 
    label7.setVisible(true);
    label8.setVisible(true);
    label9.setVisible(true);
    text1.setVisible(true);
    text2.setVisible(true); 
    text3.setVisible(true); 
    text4.setVisible(true);
    text5.setVisible(true);
    text6.setVisible(true);
    text7.setVisible(true);
    b2.addActionListener(new ActionListener(){
        public void actionPerformed(ActionEvent e){ 
            JOptionPane.showMessageDialog(null," Customer Name: " +text1.getText()+ "\n IC Number: " +text2.getText()+ "\n Age: " +text3.getText()+ "\n Mobile Number: " +text4.getText()+ "\n Rental Charger: "+ df.format(amount) );
            } 
            });
            }
else{
    JOptionPane.showMessageDialog(null,"Thank survey to Rental Car System and See you Again....!");
}
}
}
else if(value.equals("Toyota Vios")){
    if(day>0){

final double amount=(day-0)*60.00 + 100.00;
JOptionPane.showMessageDialog(null,"Vehicle type= Toyota Vios \n" + " Deposit= Rm100 \n " + " Daily Rate= 60 \n" + "days= " + day+"\n\n"+"Rental Total Charges= "+df.format(amount)); 
String st=JOptionPane.showInputDialog(null,"Do you want to continue next Process?( y/n ): "); 
if(st.equals("y")){
    label1.setVisible(false);
    label2.setVisible(false); 
    text.setVisible(false);
    combo.setVisible(false);
    b1.setVisible(false);
    b2.setVisible(true); 
    label3.setVisible(true); 
    label4.setVisible(true);
    label5.setVisible(true); 
    label6.setVisible(true);

text1.setVisible(true);
text2.setVisible(true);
text3.setVisible(true);
text4.setVisible(true);

continue..

b2.addActionListener(new ActionListener(){
    public void actionPerformed(ActionEvent e){ 
        JOptionPane.showMessageDialog(null," Customer Name: " +text1.getText()+ "\n IC Number: " +text2.getText()+ "\n Age: " +text3.getText()+ "\n Mobile Number: " +text4.getText()+ "\n Rental Charger: "+ df.format(amount) );
        }
        });
        } 
        else{ 
            JOptionPane.showMessageDialog(null,"Thank survey to Rental Car System and See you Again....!"); 
            } 
            }
            }
            else if(value.equals("Nissan Latio")){
                if(day>0){
                    final double amount=(day-0)*70.00 + 100.00;
                    JOptionPane.showMessageDialog(null,"Vehicle type= Nissan Latio \n" + " Deposit= Rm100 \n " + " Daily Rate= 70 \n" + "days= " + day+"\n\n"+"Rental Total Charges= "+df.format(amount));
                    String st=JOptionPane.showInputDialog(null,"Do you want to continue next Process?( y/n ): ");
                    if(st.equals("y")){
                        label1.setVisible(false);
                        label2.setVisible(false);
                        text.setVisible(false);
                        combo.setVisible(false);
                        b1.setVisible(false); 
                        b2.setVisible(true);
                        label3.setVisible(true);
                        label4.setVisible(true);
                        label5.setVisible(true); 
                        label6.setVisible(true);

                        text1.setVisible(true);
                        text2.setVisible(true);
                        text3.setVisible(true);
                        text4.setVisible(true);

b2.addActionListener(new ActionListener(){
    public void actionPerformed(ActionEvent e){
        JOptionPane.showMessageDialog(null," Customer Name: " +text1.getText()+ "\n IC Number: " +text2.getText()+ "\n Age: " +text3.getText()+ "\n Mobile Number: " +text4.getText()+ "\n Rental Charger: "+ df.format(amount) );
        }
        });
        }
        else{
            JOptionPane.showMessageDialog(null,"Thank survey to Rental Car System and See you Again....!");
            } 
            } 
            } 
            } 
            public static void main(String[]args){
                new RC();
            }
            }

sorry can i ask one more question if i use this application to modify connection with database is it can ?