Login.java

import javax.swing.JFrame;
import java.awt.BorderLayout;

public class Login
{
  public static void main(String[] args)
  {
    LoginGUI cuFrame = new LoginGUI();
    cuFrame.setVisible(true);
    cuFrame.setTitle("Login");
    cuFrame.setSize(300,150);
    cuFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    
  }
}

LoginGUI.java

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.BorderLayout;
import java.awt.Dimension;
import javax.swing.border.*;
import javax.swing.*;
import java.util.*;
import java.io.*;

public class LoginGUI extends JFrame
{
 private JTextField txtUser;
 private JPasswordField txtPass;
 private JTextField longID;
 
 private JLabel lblUser;
 private JLabel lblPass;
 private JLabel lblID;
 private JButton btnLogin;
 private JButton btnExit;
 private JPanel panel1;
 
 ArrayList<Person> student = new ArrayList<Person>();

 public LoginGUI() 
 {
  setLayout(new BorderLayout(10, 10));
  panel1 = new JPanel();
  panel1.setPreferredSize(new Dimension(250, 250));

  txtUser = new JTextField();
  txtUser.setPreferredSize(new Dimension(150, 20));
  txtPass = new JPasswordField();
  txtPass.setPreferredSize(new Dimension(150, 20));
  longID= new JTextField();
  longID.setPreferredSize(new Dimension(150, 20));
  lblUser = new JLabel("Username: ");
  lblPass = new JLabel("Password: ");
  lblID = new JLabel ("Student ID: ");
  
  

  btnLogin = new JButton("Login");
  btnExit = new JButton("Exit");
 
  
  panel1.add(lblUser);
  panel1.add(txtUser);
  panel1.add(lblPass);
  panel1.add(txtPass);
  panel1.add(lblID);
  panel1.add(longID);
  
  panel1.add(btnLogin);
  panel1.add(btnExit);

  ActionListener LoginAction = new LoginListener();
  btnLogin.addActionListener(LoginAction);

  ActionListener ExitAction = new ExitListener();
  btnExit.addActionListener(ExitAction);
  add(panel1, BorderLayout.CENTER);
 }
 
   {
    try 
    { 
      Scanner in = new Scanner(new File("USERDATA.txt"));
      while (in.hasNextLine())
      {
        String S=in.nextLine();
        String[] Sa= S.split(",");
        
        boolean hasUppercase = !txtPass.equals(txtPass.getText().toLowerCase()); //
        boolean hasSpecial   = !Sa[1].matches("[A-Za-z0-9 ]*");
        boolean hasSpace = Sa[1].matches(" ");
        
        if ((Sa[1].length() < 10)) 
    {
                    JOptionPane.showMessageDialog(null,
                    "Password must have a minimum of 10 characters", "Error",
                    JOptionPane.ERROR_MESSAGE);
                    
                    
    }
        
          else if (hasSpace) 
    {
                    JOptionPane.showMessageDialog(null,
                    "Password must not have a space", "Error",
                    JOptionPane.ERROR_MESSAGE);
    }
     
  
   
        else if (!hasUppercase)
           {
                     JOptionPane.showMessageDialog(null,
                    "Password must have at least 1 uppercase letter", "Error",
                    JOptionPane.ERROR_MESSAGE);
           }
        

        else if (!hasSpecial)
           {
                    JOptionPane.showMessageDialog(null,
                    "Password must have at least 1 number", "Error",
                    JOptionPane.ERROR_MESSAGE);
        }
        
        else
        {
          JOptionPane.showMessageDialog(null,
                    "Invalid Username / Password Combo", "Error",
                    JOptionPane.ERROR_MESSAGE);
        }
          in.close();
         
      }
      in.close();
    }
    catch(IOException e)
    { 
      JOptionPane.showMessageDialog(null, e.getMessage());
    }
    
  }

        
}

 class ExitListener implements ActionListener 
 {
  public void actionPerformed(ActionEvent event) 
  {
   System.exit(0);
  }
 }

 class LoginListener implements ActionListener 
 {
  public void actionPerformed(ActionEvent event) 
  {   

    boolean found = false;
    
    Person temp = new Person(username, password, studentID); //cannot find symbol
      
    for(array p : array)
   {
     if(p.compareTo(temp) == 0)
   {
    JOptionPane.showMessageDialog(null,
      "Your user account has been validated!");
   } 
   else if(p.compareTo(temp) !=0)
 {
    JOptionPane
      .showMessageDialog(null,
        "Your Username or Password is incorrect. Please try again");
   }
   txtUser.setText("");
   txtPass.setText("");
    }
  }
 }

Person.java

public class Person implements Comparable<Person>
{
  private static String username;
  private static String password;
  private static Long studentID;
  
  public Person(String username, String password, Long studentID)
  {
    this.username = User;
    this.password = Pass;
    this.studentID = ID;
  }
  

  
  
  public String getPassword ()
  {
    return this.password;
  }
  
  public String getUsername()
  {
    return this.username;
  }
  
  
  public Long getStudentID()
  {
    return this.StudentID;
  }
}

USERDATA.txt

USER1,fBqj!P4B33,900000003
USER2,2Hmkq98NW+,900000006
USER3,_SNT8wsz85,900000009
USER4,5LDz2H%t3t,900000013
USER5,at!tbX92FC,900000016