@WebServlet("/maths/multiplier")
public class ProduitServlet extends HttpServlet {

  private final CalculationDelegate calculationDelegate =
      CalculationDelegate.withDefaultParameterName(MathOperators.PRODUIT);

  @Override
  protected void doGet(HttpServletRequest req, HttpServletResponse resp)
      throws ServletException, IOException {
    calculationDelegate.doOperation(req, resp);
  }
}
 @Override
 protected void doGet(HttpServletRequest req, HttpServletResponse resp)
     throws ServletException, IOException {
   calculationDelegate.doOperation(req, resp);
 }