Please add keyboard focus events to swing calculator. Its very argent.

Question

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
A frame with a calculator panel.
class CalculatorFrame1 extends JFrame
     private static final long serialVersionUID=0;
public CalculatorFrame1()
setTitle("Calculator");
Container contentPane = getContentPane();
CalculatorPanel panel = new CalculatorPanel();
contentPane.add(panel);
pack();
setVisible(true);
public static void main(String[] args)
CalculatorFrame1 frame = new CalculatorFrame1();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//frame.show();
A panel with calculator buttons and a result display.
class CalculatorPanel extends JPanel implements KeyListener
private static final long serialVersionUID=0;
private JTextField display;
private JPanel panel;
private double result;
private String lastCommand;
private boolean start;
public CalculatorPanel()
setLayout(new BorderLayout());
result = 0;
lastCommand = "=";
start = true;
// add the display
display = new JTextField("");
// display.addKeyListener(this);
// display.addKeyListener(this);
add(display, BorderLayout.NORTH);
display.setFocusable(true);
ActionListener insert = new InsertAction();
ActionListener command = new CommandAction();
// add the buttons in a 4 x 4 grid
panel = new JPanel();
panel.setLayout(new GridLayout(5, 4));
addButton("7", insert);
addButton("8", insert);
addButton("9", insert);
addButton("/", command);
addButton("4", insert);
addButton("5", insert);
addButton("6", insert);
addButton("*", command);
addButton("1", insert);
addButton("2", insert);
addButton("3", insert);
addButton("-", command);
addButton("0", insert);
addButton(".", insert);
addButton("=", command);
addButton("+", command);
addButton("Clear", command);
add(panel, BorderLayout.CENTER);
//this.addKeyListener(this);
Adds a button to the center panel.
@param label the button label
@param listener the button listener
private void addButton(String label, ActionListener listener)
JButton button = new JButton(label);
button.addActionListener(listener);
panel.add(button);
This action inserts the button action string to the
end of the display text.
private class InsertAction implements ActionListener
public void actionPerformed(ActionEvent event)
String input = event.getActionCommand();
if (start)
display.setText("");
start = false;
display.setText(display.getText() + input);
This action executes the command that the button
action string denotes.
private class CommandAction implements ActionListener
public void actionPerformed(ActionEvent evt)
String command = evt.getActionCommand();
// System.out.println("The value clear"+command);
if (command.equals("Clear"))
          display.setText("");
          start = false;
else
if (start)
if (command.equals("-"))
display.setText(command);
start = false;
else
lastCommand = command;
else
calculate(Double.parseDouble(display.getText()));
lastCommand = command;
start = true;
Carries out the pending calculation.
@param x the value to be accumulated with the prior result.
public void calculate(double x)
if (lastCommand.equals("+")) result += x;
else if (lastCommand.equals("-")) result -= x;
else if (lastCommand.equals("*")) result *= x;
else if (lastCommand.equals("/")) result /= x;
else if (lastCommand.equals("=")) result = x;
display.setText("" + result);
public void keyTyped(KeyEvent e) {
     //You should only rely on the key char if the event
//is a key typed event.
     int id = e.getID();
     String keyString="";
     System.out.println("The value KeyEvent.KEY_TYPED"+KeyEvent.KEY_TYPED);
if (id == KeyEvent.KEY_TYPED) {
char c = e.getKeyChar();
//System.out.println("The value c"+c);
if(c=='*' || c=='/' || c=='-'||c=='+' || c=='=')
     start = true;
else
     start = false;
     keyString = display.getText()+ c ;
     System.out.println("The value keyString"+keyString);
else {
calculate(Double.parseDouble(display.getText()));
start = true;
display.setText(keyString);
public void keyPressed(KeyEvent e) {
     //You should only rely on the key char if the event
//is a key typed event.
     String keyString;
int id = e.getID();
if (id == KeyEvent.KEY_TYPED) {
char c = e.getKeyChar();
keyString = "key character = '" + c + "'";
} else {
int keyCode = e.getKeyCode();
keyString = "key code = " + keyCode
+ " ("
+ KeyEvent.getKeyText(keyCode)
+ ")";
display.setText("keyPressed:::"+keyString);**/
public void keyReleased(KeyEvent e) {
     //You should only rely on the key char if the event
//is a key typed event.
     String keyString;
int id = e.getID();
if (id == KeyEvent.KEY_TYPED) {
char c = e.getKeyChar();
keyString = "key character = '" + c + "'";
} else {
int keyCode = e.getKeyCode();
keyString = "key code = " + keyCode
+ " ("
+ KeyEvent.getKeyText(keyCode)
+ ")";
display.setText("keyReleased:::"+keyString);**/
}

Answer 1

Please state why the question is urgent?
You where given a suggestion 7 minutes after you posted the question, yet it has been over 2 hours and you have not yet responded indicating whether the suggest helped or not.
So I gues its really not the urgent after all and therefore I will ignore the question.
By the way, learn how to use the "Code Formatting Tags" when you post code, so the code you post is actually readable.