Pass User ID from one page to another from Java ArrayList

Question

I am developing a system using CRUD functionality. I am retrieving users from my database and passing these into an ArrayList where the user can click next user and previous user buttons to display each user in the system.

The code for getting the users from the database:

//refresh data from database
    public void refreshData(){
        try {
            users.clear(); //clear users array list
            
            String sqlGetTypes = "SELECT * FROM tbl_login"; //select all data from db 
            
            Connection conn = db.Connect(); //connection to db
            
            PreparedStatement psGetUsers = conn.prepareStatement(sqlGetTypes);
            
            ResultSet rs = psGetUsers.executeQuery();
            
            while (rs.next()){ //filter through users
                User u = new User(rs.getInt("id"), rs.getString("username"), 
                rs.getString("password"), rs.getString("role"));
                
                users.add(u); //add each user
            }
            
            rs = psGetUsers.executeQuery(); //execute the query
            
            this.comboBoxUserRole.removeAllItems(); //remove items from combo box
            
            while(rs.next()){
                roleTypeModel.addElement(new ComboBoxItem(rs.getInt("id"), 
                rs.getString("username")));
            }
            for (int i = 0; i < roleTypeModel.getSize(); i++){
                ComboBoxItem cbi = (ComboBoxItem)roleTypeModel.getElementAt(i); //create 
                object of type combo box item
                
                    if (cbi.getId() == users.get(currentUser).getLoginID()){
                    roleTypeModel.setSelectedItem(cbi); //select users role from selected user
                }
            }
            
            this.comboBoxUserRole.setModel(roleTypeModel); //set the user role in combo box
            
            this.txtUserID.setText(String.valueOf(users.get(currentUser).getLoginID())); //set user ID in text field
            this.txtUsername.setText(String.valueOf(users.get(currentUser).getUsername())); //set username in text field
                     
        }
        catch (Exception e){
            JOptionPane.showMessageDialog(null, "Cannot get users at this time. Error: " + e);
        }
    }

I then have a button named 'Update current user' which will redirect the user to another page in order to update that users login details. Here I am wanting to transfer the UserID over from the current user that is displayed at the time. I will then use the UserID to query the database again in the new page to identify the user, which will then be able to be updated based on the new values that the user enters.

The code for the update user page:

//refresh data from database
    public void refreshData(){
        try {
            system_users su = new system_users(); //create new instance of previous page
            String userId = (su.txtUserID.getText()); //set the ID field from previous page
            

            String sqlGetTypes = "SELECT * FROM tbl_login WHERE id = ?"; //select user from database
            
            Connection conn = db.Connect(); //connection to db
            
            PreparedStatement ps = conn.prepareStatement(sqlGetTypes);

            ps.setString(1, userID); //set ID to user ID variable
            
            ResultSet rs = ps.executeQuery();
            
            while (rs.next()){ //filter through users
                User u = new User(rs.getInt("id"), rs.getString("username"), rs.getString("password"), rs.getString("role"));
                users.add(u);
            }
            
            rs = ps.executeQuery(); //execute the query 
            
            this.comboBoxUserRole.removeAllItems();
            
            while(rs.next()){
                roleTypeModel.addElement(new ComboBoxItem(rs.getInt("id"), rs.getString("username")));
            }
 
            for (int i = 0; i < roleTypeModel.getSize(); i++){
                //JOptionPane.showMessageDialog(null, i);
                ComboBoxItem cbi = (ComboBoxItem)roleTypeModel.getElementAt(i); //create object of type combo box item
                if (cbi.getId() == users.get(currentUser).getLoginID()){
                    roleTypeModel.setSelectedItem(cbi);
                }
            }
            
            this.comboBoxUserRole.setModel(roleTypeModel);          
       this.txtUpdateUsername.setText(String.valueOf(users.get(currentUser).getUsername()));
            this.txtUpdatePassword.setText(String.valueOf(users.get(currentUser).getPassword()));
        }
        catch (Exception e){
            JOptionPane.showMessageDialog(null, "Cannot get customer information at this time. Error: " + e);
        }
    }

From this, the user is then able to overwrite the values input into the text fields and click on 'Update user' button, with the following code:

try{
            JOptionPane.showMessageDialog(null, "cbi");
            //ComboBoxItem gender = (ComboBoxItem)genderTypeModel.getSelectedItem(); //get the users role from combo box

            JOptionPane.showMessageDialog(null, "conn");
            Connection conn = db.Connect();

            String sqlInsertUser = "UPDATE tbl_login "
                    + "             SET    (username, password, role)"
                    + "             VALUES (?, ?, ?)";

            PreparedStatement ps = conn.prepareStatement(sqlInsertUser);
            ps.setString(1, this.txtUpdateUsername.getText());
            ps.setString(2, this.txtUpdatePassword.getText());
            ps.setString(3, String.valueOf(comboBoxUserRole));


            ps.executeUpdate(); //execute the update
            JOptionPane.showMessageDialog(null, "Customer has been successfully updated");
        }
        catch (Exception e){
            JOptionPane.showMessageDialog(null, "Customer could not be updated. Please try again. Error: " + e);
        }

The problem I am having is that I am currently unable to pass the UserID from the first block of code on one page, to the update user page. Is there any way to get the user ID which will change in the Array List I am using from the database, and pass this on to the next page so I am able to update my user login credentials.

Please let me know if this is able to be done :) Feel free to ask any questions if my explanation is bad. Thank you