shoppingcartservlet.java

JAVA网上书店的程序原代码,希望对大家偶用

package ebookshop.servlet;

import java.io.IOException;
import java.sql.SQLException;

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 ebookshop.shopcart.*;
import ebookshop.bean.BookBean;
import javax.servlet.*;

public class ShoppingCartServlet extends HttpServlet {
  private ServletContext sc;
  private static final String CONTENT_TYPE = "text/html; charset=GBK";

  public ShoppingCartServlet() { }  
 
  // service method, the main control method
  protected void doGet(HttpServletRequest request ,HttpServletResponse response)throws ServletException, IOException{
   response.setContentType(CONTENT_TYPE);
   String operation=request.getParameter("operation");
   if(operation==null){
     operation="";
   }
   if(operation.equalsIgnoreCase("addItem")){
     this.doAdd(request,response);
     return;
   }
   if(operation.equalsIgnoreCase("removeItem")){
     this.doRemove(request,response);
     return;
   }
   if(operation.equalsIgnoreCase("removeAll")){
     this.doRemoveAll(request,response);
     return;
   }
   this.doUnknown(request,response);
     return;
  }
  
  protected void doPost(HttpServletRequest request ,HttpServletResponse response)throws ServletException, IOException
  {
	  doGet(request,response);
  }
  
  private void doBrower(HttpServletRequest request, HttpServletResponse response)throws ServletException,IOException{
	sc=getServletContext();
	RequestDispatcher rd=sc.getRequestDispatcher("/showcart.jsp");
    rd.forward(request,response);
  }
  
  private void doBrowseErr(HttpServletRequest request, HttpServletResponse response) throws
           ServletException, IOException{
	 sc=getServletContext();
     RequestDispatcher rd=sc.getRequestDispatcher("/login.jsp");
     rd.forward(request,response);

  }

  private void doAdd(HttpServletRequest request, HttpServletResponse response)
  										throws ServletException,IOException{
    HttpSession session=request.getSession(false);
    String user = (String) session.getAttribute("userName");
    ShoppingCart cartMap=(ShoppingCart) session.getAttribute(user);
  

    if(cartMap==null){
     this.doBrowseErr(request, response);
    }

    String itemisdn=request.getParameter("isdn");
    BookBean  book = new BookBean();
    BookDetails bd= null;
    try {
      bd= book.findBookByISBN(itemisdn);
    }
    catch (SQLException ex) {
      ex.printStackTrace();
    }

    cartMap.add(itemisdn, bd);  //调用ShoppingCart的add()方法
    doBrower(request,response);
  }
  
  private void doRemove(HttpServletRequest request, HttpServletResponse response)throws ServletException,IOException{
   HttpSession session=request.getSession();
   String user = (String) session.getAttribute("userName");
   ShoppingCart cartMap=(ShoppingCart) session.getAttribute(user);
   if(cartMap==null){
     cartMap=new ShoppingCart();
    session.setAttribute("shoppingcart",cartMap);
   }

   String itemisdn=request.getParameter("isdn");
   
  
   cartMap.remove(itemisdn);
   session.setAttribute("shoppingcart",cartMap);
   doBrower(request,response);

  }
  
  private void doRemoveAll(HttpServletRequest request, HttpServletResponse response)throws ServletException,IOException{
	  
  }
  
  private void doUnknown(HttpServletRequest request, HttpServletResponse response)throws ServletException,IOException{

  }
  //Clean up resources
  public void destroy() {
  }

}