Design a Windows Desktop application and write the code that will execute according to the program requirements in Figure 4-108. Before designing the user interface, create a Use Case Definition. Before writing the code, create an event-planning document for each event in the program. Solution import java.awt.*; import java.awt.event.*; import javax.swing.*; import java.applet.*; public class IncomeTaxCalculator extends Applet implements ActionListener,WindowListener{ private Label label,label1,label2,label3; private JTextField txt,txt1,txt3,txt4; private JButton btn1,btn2; public void init(){ Frame f=new Frame(); Frame f1=new Frame(); f.setLayout(new BorderLayout()); f.setSize(1000, 300); Panel p=new Panel(); Panel pc1=new Panel(); f.add(pc1,\"South\"); f.add(p,\"North\"); label=new Label(\"Enter Income :\"); label1=new Label(\"Tax To Be Paid :\"); label2=new Label(\"Cess\"); label3=new Label(\"Income Tax\"); txt1=new JTextField(10); txt3=new JTextField(10); txt4=new JTextField(10); txt=new JTextField(10); p.add(label); p.add(txt); p.add(label3); p.add(txt4); p.add(label2); p.add(txt3); p.add(label1); p.add(txt1); btn1= new JButton(\"SUBMIT\"); btn2= new JButton(\"EXIT\"); pc1.add(btn1); pc1.add(btn2); f.setVisible(true); btn1.addActionListener(this); btn2.addActionListener(this); } public static void main(String args[]){ new IncomeTaxCalculator().init(); } @Override public void actionPerformed(ActionEvent e) { JButton btn=(JButton)e.getSource(); if(btn==btn1){ double a=Integer.parseInt(txt.getText()); double tax=0,b=0; if(a>0 && a<=160000){ txt1.setText(\"0\"); txt4.setText(\"0\"); txt3.setText(\"0\"); }else if(a>160000 && a<=300000){ a=a-160000; tax=0.1*a; txt4.setText(String.valueOf(tax)); txt3.setText(String.valueOf(tax*.03)); tax+=tax*.03; txt1.setText(String.valueOf(tax)); }else if(a>300000 && a<=500000){ a=a-300000; tax=0.2*a+14000; txt4.setText(String.valueOf(tax)); txt3.setText(String.valueOf(tax*.03)); tax+=tax*.03; txt1.setText(String.valueOf(tax)); }else if(a>500000){ a=a-500000; tax=0.3*a+54000; txt4.setText(String.valueOf(tax)); txt3.setText(String.valueOf(tax*.03)); tax+=tax*.03; txt1.setText(String.valueOf(tax)); } }else if(btn==btn2){ System.exit(0); } } @Override public void windowActivated(WindowEvent e) { } @Override public void windowClosed(WindowEvent e) { } @Override public void windowClosing(WindowEvent e) { } @Override public void windowDeactivated(WindowEvent e) { } @Override public void windowDeiconified(WindowEvent e) { } @Override public void windowIconified(WindowEvent e) { } @Override public void windowOpened(WindowEvent e) { } }.

1. Design a Windows Desktop application and write the code that will execute according to the
program requirements in Figure 4-108. Before designing the user interface, create a Use Case
Definition. Before writing the code, create an event-planning document for each event in the
program.
Solution
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.applet.*;
public class IncomeTaxCalculator extends Applet implements ActionListener,WindowListener{
private Label label,label1,label2,label3;
private JTextField txt,txt1,txt3,txt4;
private JButton btn1,btn2;
public void init(){
Frame f=new Frame();
Frame f1=new Frame();
f.setLayout(new BorderLayout());
f.setSize(1000, 300);
Panel p=new Panel();
Panel pc1=new Panel();
f.add(pc1,"South");
f.add(p,"North");
label=new Label("Enter Income :");
label1=new Label("Tax To Be Paid :");
label2=new Label("Cess");
label3=new Label("Income Tax");
txt1=new JTextField(10);
txt3=new JTextField(10);
txt4=new JTextField(10);
txt=new JTextField(10);
p.add(label);
p.add(txt);
p.add(label3);

2. p.add(txt4);
p.add(label2);
p.add(txt3);
p.add(label1);
p.add(txt1);
btn1= new JButton("SUBMIT");
btn2= new JButton("EXIT");
pc1.add(btn1);
pc1.add(btn2);
f.setVisible(true);
btn1.addActionListener(this);
btn2.addActionListener(this);
}
public static void main(String args[]){
new IncomeTaxCalculator().init();
}
@Override
public void actionPerformed(ActionEvent e) {
JButton btn=(JButton)e.getSource();
if(btn==btn1){
double a=Integer.parseInt(txt.getText());
double tax=0,b=0;
if(a>0 && a<=160000){
txt1.setText("0");
txt4.setText("0");
txt3.setText("0");
}else if(a>160000 && a<=300000){
a=a-160000;
tax=0.1*a;
txt4.setText(String.valueOf(tax));
txt3.setText(String.valueOf(tax*.03));
tax+=tax*.03;
txt1.setText(String.valueOf(tax));

3. }else if(a>300000 && a<=500000){
a=a-300000;
tax=0.2*a+14000;
txt4.setText(String.valueOf(tax));
txt3.setText(String.valueOf(tax*.03));
tax+=tax*.03;
txt1.setText(String.valueOf(tax));
}else if(a>500000){
a=a-500000;
tax=0.3*a+54000;
txt4.setText(String.valueOf(tax));
txt3.setText(String.valueOf(tax*.03));
tax+=tax*.03;
txt1.setText(String.valueOf(tax));
}
}else if(btn==btn2){
System.exit(0);
}
}
@Override
public void windowActivated(WindowEvent e) {
}
@Override
public void windowClosed(WindowEvent e) {
}
@Override
public void windowClosing(WindowEvent e) {
}
@Override
public void windowDeactivated(WindowEvent e) {
}
@Override

4. public void windowDeiconified(WindowEvent e) {
}
@Override
public void windowIconified(WindowEvent e) {
}
@Override
public void windowOpened(WindowEvent e) {
}
}