public class SignIn extends HttpServlet {
    private static final long serialVersionUID = 1L;


    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        response.setContentType("text/html;charset=UTF-8");
        PrintWriter out = response.getWriter();

        String uname = request.getParameter("uname");
        String pass = request.getParameter("pass");

            Registration.setOnline(uname);
            try {
                // loading drivers for mysql
                Class.forName("com.mysql.jdbc.Driver");

                // creating connection with the database
                Connection con = DriverManager.getConnection("jdbc:mysql://localhost:3306/ted", "root", "root");
                PreparedStatement ps = con.prepareStatement("select * from user");
                ResultSet rs = ps.executeQuery();
                out.println("<table>");
                while (rs.next()) {
                    uname = rs.getString(1);
                    pass = rs.getString(2);
                    out.println("<tr><th>" + uname +"</th><th>"+ pass + "</th></tr>");
                }
                out.println("</table>");

            } catch (Exception e) {
                e.printStackTrace();
            }


            RequestDispatcher res = request.getRequestDispatcher("html/index.html");
            res.include(request, response);

    }
}

<servlet-mapping>
  <servlet-name>SignIn</servlet-name>
  <url-pattern>/signIn</url-pattern>
</servlet-mapping>