protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

    Connection con = connect();
...
}

private Connection connect() {
     try {
         Class.forName("com.mysql.jdbc.Driver");
         return DriverManager.getConnection("jdbc:mysql://localhost:3306/chat", "serveradmin", "password");
     } catch (Exception e) {
         System.out.println("Failed to obtain connection: " + e);
         System.out.println(e.getStackTrace());
         return null;
     }
 }