cartservlet.java

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/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */

package cart.servlet;

import ejb3.day2.Product;
import ejb3.day2.SalesLine;
import ejb3.day2.ShoppingCart;
import java.io.*;
import java.net.*;

import java.util.Set;
import javax.servlet.*;
import javax.servlet.http.*;

/**
 *
 * @author user
 */
public class CartServlet extends HttpServlet {
   private Set<Product> products;
    public void init(){
        ServletContext sc = this.getServletContext();
        products = (Set<Product>)sc.getAttribute("products");
    }
    
    private Product get(int id){
        for(Product p : products){
            if(p.getId() == id) return p;
        }
        
        return null;
    }
    /** 
    * Processes requests for both HTTP <code>GET</code> and <code>POST</code> methods.
    * @param request servlet request
    * @param response servlet response
    */
    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        String idStr = request.getParameter("id");
        String numStr = request.getParameter("num");
        int id = Integer.parseInt(idStr);
        int num = Integer.parseInt(numStr);
        Product p = get(id);
        HttpSession ses = request.getSession();
        ShoppingCart cart = (ShoppingCart)ses.getAttribute("cart");
        SalesLine l = new SalesLine(p,num);
        String nextScreen = "/listProducts.jsp";
        if(request.getServletPath().equals("/add.do")){
            cart.add(l);
            nextScreen = "/list.jsp";
        }else if(request.getServletPath().equals("/remove.do")){
            cart.remove(l);
        }else if(request.getServletPath().equals("/list.do")){
            cart.list();
        }
        
        this.getServletContext().getRequestDispatcher(nextScreen)
                .forward(request, response);
        
    } 

    // <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
    /** 
    * Handles the HTTP <code>GET</code> method.
    * @param request servlet request
    * @param response servlet response
    */
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        processRequest(request, response);
    } 

    /** 
    * Handles the HTTP <code>POST</code> method.
    * @param request servlet request
    * @param response servlet response
    */
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        processRequest(request, response);
    }

    /** 
    * Returns a short description of the servlet.
    */
    public String getServletInfo() {
        return "Short description";
    }
    // </editor-fold>
}