shoppservlet.java

这是一个购物车系统

package shoppcart;

import java.io.IOException;
import java.io.PrintWriter;

import java.util.*;

import javax.xml.parsers.*;

import org.w3c.dom.*;

import javax.servlet.*;
import javax.servlet.http.*;

public class ShoppServlet extends HttpServlet {
    private static final String CONTENT_TYPE = "text/html; charset=UTF-8";
    private Document document;

    public void init(ServletConfig config) throws ServletException {
        super.init(config);
    }

    public void doGet(HttpServletRequest request, 
                      HttpServletResponse response) throws ServletException, IOException {response.setContentType(CONTENT_TYPE);
        PrintWriter out = response.getWriter();
        HttpSession session=request.getSession(true);
        
        StringBuffer content=new StringBuffer(""); 
        response.setContentType("text/xml"); 
        response.setHeader("Cache-Control","no-cache");
        content.append("<?xml version=\"1.0\"   encoding=\"UTF-8\" ?>");
        content.append("<list>");
        ArrayList<BookCount> counts = (ArrayList<BookCount>)session.getAttribute("counts");
        ArrayList<Product> list=(ArrayList<Product>)session.getAttribute("list");
        if(list==null){
            content.append("<product>");
            content.append("<id>0</id>");
            content.append("</product>");
        }
        else{
            Iterator iterator=list.iterator();
            while(iterator.hasNext()){
                Product product=(Product)iterator.next();
                for(int i=0;i<counts.size();i++){
                    if(product.getID().equals(counts.get(i).getProductID())){
                        content.append("<product>");
                        content.append("<id>" + product.getID() + "</id>");
                        content.append("<name>"+ product.getName() +"</name>");
                        content.append("<publisher>"+product.getPublisher() +"</publisher>");
                        content.append("<price>" + product.getPrice()+"</price>");
                        content.append("<num>" + counts.get(i).getCount() +"</num>");
                        content.append("</product>"); 
                    }
                }
            }
        }
        
        content.append("</list>");
        out.print(content);
        out.close();
    }
}