modifycartservlet.java

该项目为网上书店

package org.myrose.servlet;

import java.io.IOException;
import java.io.PrintWriter;
import java.util.Vector;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.myrose.beans.BookCart;

public class ModifyCartServlet extends HttpServlet {

	/**
	 * Constructor of the object.
	 */
	public ModifyCartServlet() {
		super();
	}

	/**
	 * Destruction of the servlet. <br>
	 */
	public void destroy() {
		super.destroy(); // Just puts "destroy" string in log
		// Put your code here
	}

	/**
	 * The doGet method of the servlet. <br>
	 *
	 * 此方法用来修改购物车物品信息
	 * 
	 * @param request the request send by the client to the server
	 * @param response the response send by the server to the client
	 * @throws ServletException if an error occurred
	 * @throws IOException if an error occurred
	 */
	public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {

		response.setContentType("text/html;charset=GBK");
		request.setCharacterEncoding("GBK");
		
	}

	/**
	 * The doPost method of the servlet. <br>
	 *
	 * This method is called when a form has its tag value method equals to post.
	 * 
	 * @param request the request send by the client to the server
	 * @param response the response send by the server to the client
	 * @throws ServletException if an error occurred
	 * @throws IOException if an error occurred
	 */
	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {

		response.setContentType("text/html;charset=GBK");
		request.setCharacterEncoding("GBK");
		
		HttpSession session = request.getSession();
		
		Vector cart=(Vector)session.getAttribute("cart");
		Vector newcart=new Vector();
		for(int i=0;i<cart.size();i++){
			String number=request.getParameter("num"+i);
			if(number.equals("0")){
				request.setAttribute("isok", "0");
				request.getRequestDispatcher("cart_see.jsp").forward(request, response);
				return;
			}
			if(number.equals("")){
				request.setAttribute("isok", "null");
				request.getRequestDispatcher("cart_see.jsp").forward(request, response);
				return;
			}
			BookCart bookcart=(BookCart)cart.elementAt(i);
			String num=request.getParameter("num"+i);
			int newnum=Integer.parseInt(num);
			bookcart.setNum(newnum);
			if(newnum!=0){
				newcart.addElement(bookcart);
				}
		}
		session.setAttribute("cart",newcart);
		response.sendRedirect("cart_see.jsp");
	}

	/**
	 * Initialization of the servlet. <br>
	 *
	 * @throws ServletException if an error occure
	 */
	public void init() throws ServletException {
		// Put your code here
	}

}