public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
String id = request.getParameter("id");
BusinessService service = new BusinessServiceImpl();
Book book = service.findBook(id);
Cart cart = (Cart) request.getSession().getAttribute("cart");
if (cart == null) {
cart = new Cart();
request.getSession().setAttribute("cart", cart);
}
cart.add(book);
response.sendRedirect(request.getContextPath() + "/client/listcart.jsp");
}
