Why wont my java UI code code connect to my databased. I keep getting errors:

package MedicalLoginApp;

import javax.swing.$*$;

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

import java.io$.$FileWriter;

import java.io$.$IOException;

import java.sql$.$ResultSet;

import java.sql$.$SQLException;

import com.opencsv.CSVWriter;

public class MedicalAppUI extends JFrame $\{$

private static final long serialVersionUID $=1$L;

private JTextField usernameField;

private JPasswordField passwordField;

public MedicalAppUI$()\{$

JLabel usernameLabel $=$ new JLabel$("$Doctor$\text{'}$s Username:"$)$;

JLabel passwordLabel $=$ new JLabel$("$Doctor$\text{'}$s Password:"$)$;

usernameField $=$ new JTextField$()$;

passwordField $=$ new JPasswordField$()$;

JButton loginButton $=$ new JButton$("$Login$")$;

JButton exportButton $=$ new JButton$("$Export to CSV$")$;

setLayout$($new BoxLayout$($getContentPane$(),$ BoxLayout.Y$\_$AXIS$))$;

add$($usernameLabel$)$;

add$($usernameField$)$;

add$($passwordLabel$)$;

add$($passwordField$)$;

add$($loginButton$)$;

add$($exportButton$)$;

loginButton$.$addActionListener$($new ActionListener$()\{$

@Override

public void actionPerformed$($ActionEvent e$)\{$

String username $=$ usernameField.getText$()$;

char$[]$ password $=$ passwordField.getPassword$()$;

try $\{$

if $($DatabaseConnector$.$authenticate$($username$,$ new String$($password$)))\{$

MedicalAppMain$()$;

$\}$ else $\{$

JOptionPane.showMessageDialog$($MedicalAppUI$.$this, "Sorry, Invalid username or password"$)$;

$\}$

$\}$ catch $($SQLException ex$)\{$

JOptionPane.showMessageDialog$($MedicalAppUI$.$this, "There is an error connecting to the database"$)$;

$\}$

$\}$

$\})$;

exportButton.addActionListener$($new ActionListener$()\{$

@Override

public void actionPerformed$($ActionEvent e$)\{$

exportDataToCSV$()$;

$\}$

$\})$;

setDefaultCloseOperation$($JFrame$.$EXIT$\_$ON$\_$CLOSE$)$;

pack$()$;

setLocationRelativeTo$($null$)$;

setVisible$($true$)$;

$\}$

private void exportDataToCSV$()\{$

try $\{$

ResultSet resultSet $=$ DatabaseConnector.getAllDoctors$()$;

String csvFilePath $=$ "output.csv$"$;

try $($CSVWriter writer $=$ new CSVWriter$($new FileWriter$($csvFilePath$)))\{$

writer.writeNext$($new String$[]\{"$Doctor$\_$FirstName", "Doctor$\_$LastName", "Department"$\})$;

while $($resultSet$.$next$())\{$

String$[]$ data $=\{$

resultSet.getString$("$Doctor$\_$FirstName"$),$

resultSet.getString$("$Doctor$\_$LastName"$),$

resultSet.getString$("$Department$")$

$\}$;

writer.writeNext$($data$)$;

$\}$

JOptionPane.showMessageDialog$($MedicalAppUI$.$this, "Data exported to CSV successfully. File: $"+$ csvFilePath$)$;

$\}$

$\}$ catch $($SQLException $|$ IOException e$)\{$

JOptionPane.showMessageDialog$($MedicalAppUI$.$this, "Error exporting data to CSV$")$;

$\}$

$\}$

private void MedicalAppMain$()\{$

this.dispose$()$;

$\}$

public static void main$($String$[]$ args$)\{$

SwingUtilities.invokeLater$(()->$ new MedicalAppUI$())$;

$\}$

$\}$

and this is mypackage MedicalLoginApp;

import java.sql$.$Connection;

import java.sql$.$DriverManager;

import java.sql$.$PreparedStatement;

import java.sql$.$ResultSet;

import java.sql$.$SQLException;

import java.util.List;

public class DatabaseConnector $\{$

private static final String URL $="$jdbc:mysql:$//$localhost:$3306/$Medical$\_$login$"$;

private static final String USER $=$ "Username";

private static final String PASSWORD $=$ "Password";

public static Connection getConnection$()$ throws SQLException $\{$

return DriverManager.getConnection$($URL$,$ USER, PASSWORD$)$;

$\}$

public static boolean authenticate$($String Username, String Password$)$ throws SQLException $\{$

String sql $=$ "SELECT $*$ FROM Users WHERE username $=?$ AND password $=?"$;

try $($Connection connection $=$ getConnection$()$;

PreparedStatement statement $=$ connection.prepareStatement$($sql$))\{$

statement.setString$(1,$ Username$)$;

statement.setString$(2,$ Password$)$;

try $($ResultSet resultSet $=$ statement.executeQuery$())\{$

return resultSet.next$()$;

$\}$

$\}$

$\}$

public static void insertDoctorsData$($List data$)$ throws SQLException $\{$

String sql $=$ "INSERT INTO Doctors $($Doctor$\_$FirstName, Doctor$\_$LastName, Department$)$ VALUES $(?,?,?)"$;

try $($Connection connection $=$ getConnection$()$;

PreparedStatement preparedStatement $=$ connection.prepareStatement$($sql$))\{$ database connector code: