Very simple app, why am I getting errors?

Question

1: I can't figure out why the button doesn't work. I just want it to update the JTextField so I know it's registered a click.
2: I run this program using "java Login" on the command line. The errors scroll by and I can't even see what they are. Is there some way to capture the errors?
//     Login - a simple java class for logging in to applets
/*     doc goes here
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
public class Login extends JFrame implements ActionListener
{     JPanel                northPanel;
     JTextField     fldLogin;
     JTextField     fldPassword;
     JPanel               southPanel;
     JButton               btnSubmit;
     JButton               btnCancel;
     public Login()
     {     northPanel = new JPanel();
          northPanel.setLayout(new GridLayout(2,2));
          northPanel.add(new JLabel(" Login: "));
          northPanel.add(new JTextField(20));
          northPanel.add(new JLabel(" Password: "));
          northPanel.add(new JTextField(20));
          southPanel = new JPanel();
          btnSubmit = new JButton("Submit");
          btnSubmit.setActionCommand("Submit");
          btnSubmit.addActionListener(this);
          btnCancel = new JButton("Cancel");
          btnCancel.setActionCommand("Cancel");
          btnCancel.addActionListener(this);
          southPanel.add(btnSubmit);
          southPanel.add(btnCancel);
          getContentPane().setLayout(new BorderLayout());
          getContentPane().add("North",northPanel);
          getContentPane().add("South",southPanel);
          //setSize(200,100);
          addWindowListener(new WindowAdapter(){public void windowClosing(WindowEvent e){System.exit(0);}});
     public void clearLogin()
     {     fldLogin.setText("");
     public void actionPerformed(ActionEvent e)
     {     if (e.getActionCommand() == "Submit")
          {     //do nothing
               //fldLogin.setText("1");
               clearLogin();
          if (e.getActionCommand() == "Cancel");
          {     //System.exit(0);
               //fldPassword.setText("2");
     public static void main(String args[])
     {     Login thisLogin = new Login();
          thisLogin.pack();
          thisLogin.setLocation(100,100);
          thisLogin.show();
}

Answer 1

JTextField     fldLogin;not instiated
public void clearLogin()
{     fldLogin.setText("");above will throw
{     if (e.getActionCommand() == "Submit")change == to equalsIgnoreCase
if (e.getActionCommand() == "Cancel");change == to equalsIgnoreCase
and remove the trailing ';'
and use else if