Moving methods to a new class

Question

I have a class with my GUI and methods, but i want to move my methods to their own class.
import java.awt.Container;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.awt.*;
import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JTextField;
import javax.swing.*;
public class Login extends JDialog implements ActionListener
ArrayList personsList;
PersonDAO pDAO;
JLabel userName, passWord;
JTextField userName1;
JPasswordField passWord1;
JButton jbnClear, jbnSubmit, jbnCancel;
String userName2, passWord2;
Container cPane;
public Login(JFrame father) {
super(father);
createGUI();
userName2  = "";
passWord2   = "";
personsList = new ArrayList();
pDAO = new PersonDAO();     
public void createGUI(){
cPane = getContentPane();
setLayout(new GridBagLayout());
//Arrange components on contentPane and set Action Listeners to each JButton
arrangeComponents();
setSize(210,170);
setTitle("Login");
setResizable(false);
setVisible(true);
setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE);
public void arrangeComponents(){
userName = new JLabel("Username");
passWord = new JLabel("Password");
userName1   = new JTextField(20);
passWord1   = new JPasswordField(20);
jbnClear  = new JButton("Clear");
jbnSubmit = new JButton("Submit");
jbnCancel = new JButton("Cancel");
GridBagConstraints gridBagConstraintsx01 = new GridBagConstraints();
gridBagConstraintsx01.gridx = 0;
gridBagConstraintsx01.gridy = 0;
gridBagConstraintsx01.insets = new Insets(5,5,5,5);
cPane.add(userName, gridBagConstraintsx01);
GridBagConstraints gridBagConstraintsx02 = new GridBagConstraints();
gridBagConstraintsx02.gridx = 1;
gridBagConstraintsx02.insets = new Insets(5,5,5,5);
gridBagConstraintsx02.gridy = 0;
gridBagConstraintsx02.gridwidth = 2;
gridBagConstraintsx02.fill = GridBagConstraints.BOTH;
cPane.add(userName1, gridBagConstraintsx02);
GridBagConstraints gridBagConstraintsx03 = new GridBagConstraints();
gridBagConstraintsx03.gridx = 0;
gridBagConstraintsx03.insets = new Insets(5,5,5,5);
gridBagConstraintsx03.gridy = 1;
cPane.add(passWord, gridBagConstraintsx03);
GridBagConstraints gridBagConstraintsx04 = new GridBagConstraints();
gridBagConstraintsx04.gridx = 1;
gridBagConstraintsx04.insets = new Insets(5,5,5,5);
gridBagConstraintsx04.gridy = 1;
gridBagConstraintsx04.gridwidth = 2;
gridBagConstraintsx04.fill = GridBagConstraints.BOTH;
cPane.add(passWord1, gridBagConstraintsx04);
GridBagConstraints gridBagConstraintsx09 = new GridBagConstraints();
gridBagConstraintsx09.gridx = 0;
gridBagConstraintsx09.gridy = 4;
gridBagConstraintsx09.insets = new Insets(5,5,5,5);
cPane.add(jbnClear, gridBagConstraintsx09);
GridBagConstraints gridBagConstraintsx10 = new GridBagConstraints();
gridBagConstraintsx10.gridx = 1;
gridBagConstraintsx10.gridy = 4;
gridBagConstraintsx10.insets = new Insets(5,5,5,5);
cPane.add(jbnSubmit, gridBagConstraintsx10);
GridBagConstraints gridBagConstraintsx11 = new GridBagConstraints();
gridBagConstraintsx11.gridx = 1;
gridBagConstraintsx11.gridy = 5;
gridBagConstraintsx11.insets = new Insets(5,5,5,5);
cPane.add(jbnCancel, gridBagConstraintsx11);
jbnClear.addActionListener(this);
jbnSubmit.addActionListener(this);
jbnCancel.addActionListener(this);
public void actionPerformed (ActionEvent e){
if (e.getSource() == jbnClear){
clear();
else if (e.getSource() == jbnSubmit){               
//Submit();
else if (e.getSource() == jbnCancel){               
cancel();
String getUsername() {
return userName1.getText();
String getPassword() {
return new String(passWord1.getPassword());
public void clear(){
userName1.setText("");
passWord1.setText("");
personsList.clear();
public void cancel(){
this.dispose();
public void Submit(){
userName2 = getUsername();
passWord2 = getPassword();
PersonInfo person = new PersonInfo(userName2, passWord2);
if(userName2.equals("") || passWord2.equals("")){
JOptionPane.showMessageDialog(null, "Please complete all fields.");
else
pDAO.loginPerson(person);
}If i do move them to their own class, in the submit method, i need to get the username. If i try
userName2 = Login.getUsername();I am told i non static method getUsername() cannot be referenced from a static context. How can i overcome this?

Answer 1

nick2price wrote:
well, DrLaszloJamf, thats answered it straight away. I always thought that to get an instance of another class, i had to do somthing like
Login log = new Login();But it can be done just like
private Login logI think i now understand, the top example creates a new instance of the class and passes it what is in the constructor, which would be good to use if i wanted to run the class through an event or somthing. And the second example just creates a simple instance of the class.No, that is wrong. The second line defines an instance field named log. Unless you initialize it elsewhere, this line leaves the variable with the value null. No constructor is called because of that line.
Suggestion: you have to learn to crawl before you can learn to walk. You don't even know the fundamentals of Java -- what static means, what it means to define a field. You shouldn't be touching Swing for at least another year. You need to learn the basics, first.