Can anyone see my error

Question

public class Customer extends JFrame implements ActionListener
     //Labels to identify the text Fields
     private JLabel custName;
     private JLabel custAddress;
     public Customer() {};
     public void addCust()
          //String for Labels
          String nameString = "Customer Name ";
          String addrString = "Customer Address ";
          //Text Fields for data Entry
          JTextField nameField;
          JTextField addrField;
          String newline = "\n";
          //create the labels
          custName = new JLabel(nameString);
          custAddress = new JLabel(addrString);
          //create Textfield
          nameField = new JTextField(20);
          addrField = new JTextField(30);
          custName.setLabelFor(nameField);
          custAddress.setLabelFor(addrField);
          JPanel labelPane = new JPanel();
          labelPane.setLayout(new GridLayout(0, 1));
          labelPane.add(custName);
     labelPane.add(custAddress);
          JPanel fieldPane = new JPanel();
     fieldPane.setLayout(new GridLayout(0, 1));
     fieldPane.add(nameField);
     fieldPane.add(addrField);
          JPanel contentPane = new JPanel();
     contentPane.setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));
     contentPane.setLayout(new BorderLayout());
     contentPane.add(labelPane, BorderLayout.CENTER);
     contentPane.add(fieldPane, BorderLayout.EAST);
          setContentPane(contentPane);
     public static void main(String[] args) {
Customer demo = new Customer();
demo.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
demo.addCust();
demo.pack();
demo.setVisible(true);
apprently, an identifier is required at demo.addCust().what does that mean?

Answer 1

demo.addWindowListener(
//THIS IS THE WINDOW ADAPTER YOU WANT TO ADD
//this is a mixture of "class WindowAdapter" and
//new WindowAdapter (do you get inner classes?)
new WindowAdapter() {
//THIS IS THE METHOD REQUIRED FOR THE WINDOW ADAPTER
public void windowClosing(WindowEvent e) {
System.exit(0);
}//END OF METHOD
//This is just floating in the middle of your class decleration, why?
//This should not be here
demo.addCust();
}//End class decleration
);//end of addWindowListener() method