problem trying to get the program for my logon screen working

hello.

i have developed a simple logon program. when i try to compile the program, i get 5 errors (errors + code are shown below). what in god's name are causing these errors and how can they be fixed?

thank you for your generous assistance.

-jGRASP exec: javac -g E:\CP4B Project\LogOn.java

LogOn.java:50: cannot find symbol

symbol: variable logOn

logOn = null;

^

LogOn.java:72: cannot find symbol

symbol : method setVisible(boolean)

location: class User

setVisible(false);

^

LogOn.java:83: cannot find symbol

symbol : method setVisible(boolean)

location: class User

setVisible(false);

^

LogOn.java:109: cannot find symbol

symbol : method setVisible(boolean)

location: class Administrator

setVisible(false);

^

LogOn.java:120: cannot find symbol

symbol : method setVisible(boolean)

location: class Administrator

setVisible(false);

^

5 errors

-jGRASP wedge2: exit code for process is 1.

-jGRASP: operation complete.

import java.awt.*;

import java.awt.event.*;

import javax.swing.*;

publicclass LogOnextends JFrame{

JTextField jtfUN =new JTextField(20);

JPasswordField jtfPW =new JPasswordField(20);

JButton jbOK =new JButton("OK");

JButton jbCancel =new JButton("Cancel");

public LogOn(){

super("Welcome to Home Entertainment");

setSize(250, 250);

setDefaultCloseOperation(EXIT_ON_CLOSE);

JPanel jp =new JPanel();

JLabel unLabel =new JLabel("Username: ");

JLabel pwLabel =new JLabel("Password: ");

jp.add(unLabel);

jp.add(jtfUN);

jp.add(pwLabel);

jp.add(jtfPW);

jp.add(jbOK);

jp.add(jbCancel);

setContentPane(jp);

pack();

jbOK.addActionListener(new ActionListener(){

publicvoid actionPerformed(ActionEvent e){

User u =new User();

u.doLogOn();

u.username = jtfUN.getText().trim();

u.password =new String(jtfPW.getPassword());

Administrator a =new Administrator();

a.doLogOn();

a.username = jtfUN.getText().trim();

a.password =new String(jtfPW.getPassword());

}

});

jbCancel.addActionListener(new ActionListener(){

publicvoid actionPerformed(ActionEvent e){

logOn =null;

setVisible(false);

}

});

}

publicstaticvoid main(String[] args){

LogOn logOn =new LogOn();

}

}

class User{

String username;

String password;

String[] userUsernameArray ={"Ann Smyth","John Murphy"};

String[] userPasswordArray ={"1","2"};

publicvoid doLogOn(){

int i, j;

for(i = 0; i < userUsernameArray.length; i++){

if(username.equals(userUsernameArray[i])){

setVisible(false);

//UserMainMenu umm = new UserMainMenu();

//umm.setVisible(true);

}

else{

JOptionPane.showMessageDialog(null,"Error\n\nYou have entered an incorrect username and/or password\nPlease try again", null, JOptionPane.ERROR_MESSAGE);

}

}

for(j = 0; j < userPasswordArray.length; j++){

if(password.equals(userPasswordArray[j])){

setVisible(false);

//UserMainMenu umm = new UserMainMenu();

//umm.setVisible(true);

}

else{

JOptionPane.showMessageDialog(null,"Error\n\nYou have entered an incorrect username and/or password\nPlease try again", null, JOptionPane.ERROR_MESSAGE);

}

}

}

}

class Administrator{

String username;

String password;

String[] adminUsernameArray ={"Administrator"};

String[] adminPasswordArray ={"0"};

publicvoid doLogOn(){

int k, l;

String username;

String password;

String[] adminUsernameArray ={"Administrator"};

String[] adminPasswordArray ={"0"};

for(k = 0; k < adminUsernameArray.length; k++){

if(username.equals(adminUsernameArray[k])){

setVisible(false);

//AdminMainMenu amm = new AdminMainMenu();

//amm.setVisible(true);

}

else{

JOptionPane.showMessageDialog(null,"Error\n\nYou have entered an incorrect username and/or password\nPlease try again", null, JOptionPane.ERROR_MESSAGE);

}

}

for(l = 0; l < adminPasswordArray.length; l++){

if(password.equals(adminPasswordArray[l])){

setVisible(false);

//AdminMainMenu amm = new AdminMainMenu();

//amm.setVisible(true);

}

else{

JOptionPane.showMessageDialog(null,"Error\n\nYou have entered an incorrect username and/or password\nPlease try again", null, JOptionPane.ERROR_MESSAGE);

}

}

}

}

[8829 byte] By [james-mcfaddena] at [2007-11-27 10:23:27]
# 1

Pls. Post only once.

I think somebody already answered your problem in your other post.

Yannixa at 2007-7-28 17:22:00 > top of Java-index,Desktop,Core GUI APIs...