Javaweb构建一个小型的购物车模块，源代码开源

1.Arms.java2.ArmsDB.java3.ListArmsServlet.java4.PurchaseArms.java5.CartServlet.java

package top.imustshop;

import java.io.Serializable;



public class Arms implements Serializable {
    
    private static final long serialVersionUID=1L;
    
    private String id;
    private String name;
    public Arms(){
    }
    public Arms(String id ,String name){
        this.id=id;
        this.name=name;
    }
    public String getId(){
        return id;
    }
    public void setId(String id){
        this.id=id;
    }
    public String getName(){
        return name;
    }
    public void setName(String name){
        this.name=name;
    }

}

package top.imustshop;

import java.util.Collection;
import java.util.linkedHashMap;
import java.util.Map;


public class ArmsDB {
    
    private static Map Arms = new linkedHashMap();

    static {
        Arms.put("1", new Arms("1", "W8fuckcdn"));
        Arms.put("2", new Arms("2", "御剑"));
        Arms.put("3", new Arms("3", "中国蚁剑"));
        Arms.put("4", new Arms("4", "unlead gif"));
        Arms.put("5", new Arms("5", "Wireshark"));
    }

    
    public static Collection getAll() {
        return Arms.values();
    }

    
    public static Arms getArms(String id) {
        return Arms.get(id);
    }
}

package top.imustshop;

import javax.servlet.*;
import javax.servlet.http.*;
import javax.servlet.annotation.*;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Collection;




public class ListArmsServlet extends HttpServlet {
    private static final long serialVersionUID=1L;

    
    public void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        resp.setContentType("text/html;charset=utf-8");
        PrintWriter out=resp.getWriter();

        
        Collection Arms = ArmsDB.getAll();
        out.write("军火库：
");
        for(Arms Arm:Arms){
            
            String url ="/purchase?id="+Arm.getId();
            HttpSession s=req.getSession();
            String newUrl=resp.encodeRedirectURL(url);
            out.write(Arm.getName()+"    "+"+newUrl
                    +"'>点击购买
");
        }
    }


    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    }
}

package top.imustshop;

import javax.servlet.*;
import javax.servlet.http.*;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;


public class PurchaseArms extends HttpServlet {
    private static final long serialVersionUID=1L;

    
    public void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        // 获取用户购买的商品，指定id的
        String id = req.getParameter("id");
        if (id == null) {
            // 如果id为null，重定向到listarms页面
            String url = "/listarms";
            resp.sendRedirect(url);
            return;
        }
        Arms book = ArmsDB.getArms(id);
        // 创建或者获得用户的Session对象
        HttpSession session = req.getSession();
        // 从Session对象中获得用户的购物车
        List cart = (List) session.getAttribute("cart");
        if (cart == null) {
            // 首次购买。为用户创建一个购物车(List集合模拟购物车)
            cart = new ArrayList();
            // 将购物车存入Session对象
            session.setAttribute("cart", cart);
        }
        // 将商品放入购物车
        cart.add(book);
        // 创建cookie存放Session的标识号
        cookie cookie = new cookie("JSESSIONID", session.getId());
        cookie.setMaxAge(60 * 30);
        cookie.setPath("/");
        resp.addcookie(cookie);
        // 重定向到购物车页面
        String url = "/cart";
        String newurl = resp.encodeRedirectURL(url);
        resp.sendRedirect(newurl);
    }

    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    }
}

package top.imustshop;
import javax.servlet.*;
import javax.servlet.http.*;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.List;



public class CartServlet extends HttpServlet {

    
    public void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        resp.setContentType("text/html;charset=utf-8");
        PrintWriter out = resp.getWriter();
        List cart = null;
        // 变量purFlag标记用户是否买过软件
        boolean purFlag = true;
        // 获得用户的session
        HttpSession session = req.getSession(false);

        // 如果session为null，purFlag置为false，表示用户没有买过软件
        if (session == null) {
            purFlag = false;
        } else {
            // 获得用户购物车
            cart =(List) session.getAttribute("cart");
            // 如果用的购物车为null，purFlag置为false
            if (cart == null) {
                purFlag = false;
            }
        }
        
        if (!purFlag) {
            out.write("对不起！您还没有购买任何商品！ 
");
        } else {
            // 否则显示用户购买软件列表的信息
            out.write("您购买的软件列表：
");
            double price = 0;
            for (Arms arm : cart) {
                out.write(arm.getName() + "
");
            }
        }
    }


    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    }
}

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