JavaBean does not work

I have these code for JavaBean but they do not work properly.

1/

import java.util.*;

public class NumberEvent extends EventObject{

public int number1, number2;

public NumberEvent(Object o, int number1, int number2) {

super(o);

this.number1=number1;

this.number2=number2;

}

}

2/

import java.util.*;

public interface NumberEnteredListener extends EventListener{

public void arithmeticPerformed(NumberEvent mec);

}

3/ This code I use NetBean IDE 5.0 to make

import java.io.Serializable;

import java.awt.*;

import java.awt.event.*;

import javax.swing.*;

import java.util.*;

public class NumberBean extends javax.swing.JPanel implements ActionListener, Serializable{

public NumberBean() {

initComponents();

}

NumberEnteredListener me1;

public void addNumberListener(NumberEnteredListener me1){

this.me1=me1;

}

NumberEvent mec;

public void fireNumberEvent(NumberEvent mec){

me1.arithmeticPerformed(mec);

}

public void actionPerformed(ActionEvent ae){

if(ae.getSource()==ok){

int f1=Integer.parseInt(tf1.getText());

int f2=Integer.parseInt(tf2.getText());

mec=new NumberEvent(ok, f1, f2);

fireNumberEvent(mec);

}

}

4/

import javax.swing.*;

import java.awt.event.*;

import java.util.*;

public class ArithmeticPerformer extends JFrame implements NumberEnteredListener{

NumberBean meb;

public ArithmeticPerformer() {

super("Arithmetic Caculations");

meb=new NumberBean();

getContentPane().add(meb);

meb.addNumberListener(this);

}

public void arithmeticPerformed(NumberEvent mec){

int result=mec.number1+mec.number2;

String temp="The result of adding the numbers is : " + String.valueOf(result);

JOptionPane.showMessageDialog(this, temp);

}

public static void main(String arg[]){

ArithmeticPerformer mec=new ArithmeticPerformer();

mec.setSize(300, 300);

mec.setVisible(true);

}

}

[2159 byte] By [Nguyen_Toma] at [2007-10-3 3:48:36]
# 1

Compilation completed with 5 errors and 0 warnings

NumberBean.java

Error:Error:line (12)cannot find symbol method initComponents()

Error:Error:line (31)cannot find symbol variable ok

Error:Error:line (33)cannot find symbol variable tf1

Error:Error:line (34)cannot find symbol variable tf2

Error:Error:line (35)cannot find symbol variable ok

UncleSAMa at 2007-7-14 21:45:38 > top of Java-index,Desktop,Developing for the Desktop...