addcart.java

书店实现用struts实现的一个系统 采用mysql数据库

/**
 * 该Servlet用于向购物车中添加图书
 */
import java.io.*;
import java.sql.*;
import java.util.*;
import javax.servlet.*;
import javax.servlet.http.*;
import bean.CartInf;
import bean.StrClass;

public class AddCart extends HttpServlet{
	public void doGet(HttpServletRequest request, HttpServletResponse response) 
	throws ServletException, IOException{
		HttpSession session=request.getSession();
		String toJsp="/addCartSuccess.jsp";
		String bookId=request.getParameter("bookId");
		StrClass bookNum=new StrClass(request.getParameter("bookNum"));
		
		/* 检测用户输入所需数量是否为整数 */
		if(!bookNum.isNum()){
			request.setAttribute("errInf","*请输入自然数");
			toJsp="/addCart.jsp";
		} else {
			Vector list=new Vector();
			if(session.getAttribute("cartList")!=null){
				list=(Vector)session.getAttribute("cartList");
				session.removeAttribute("cartList"); 
				for(int i=0;i<list.size();i++){
					CartInf cart =(CartInf)list.elementAt(i);    
					if(bookId.equals(cart.getBookId())){                            	
						list.removeElementAt(i);                   
						break;                                     
			 		}                                              
			 	} 
			}
			
			/* 添加图书至购物车 */
			CartInf cart=new CartInf(bookId,bookNum.toInt());
			list.addElement(cart);
			session.setAttribute("cartList",list);        
		}
		RequestDispatcher dispatcher = 
		                  request.getRequestDispatcher(toJsp);		            
		dispatcher.forward(request, response); 
	}
	
	public void doPost(HttpServletRequest request, HttpServletResponse response)
	throws ServletException, IOException {
		doGet(request,response);
	}
}