javaEE开发案例——购物车

一、页面

流程：登录页面(login.jsp)——>购物大厅页面(hall.jsp)——>购物车页面(showMyCart.jsp)——>订单页面(myorder.jsp)——>订单确认页面(orderOK.jsp)

二、页面+控制

加上控制逻辑之后：

登录页面(login.jsp)—>登录控制页面(GoHallUIServlet)—>购物大厅页面(hall.jsp)—>购物控制页面(ShoppingClServlet)—>购物车页面(showMyCart.jsp)—>订单控制页面(GoMyOrderServlet)—>订单页面(myorder.jsp)—>(订单提交处理SubmitOrderServlet)—>订单确认页面(orderOK.jsp)

三、页面+控制+DAO

后台数据库，对应四张表：分别是

用户表uses：（user_id,user_name,user_pwd,user_email,user_tel,user_grade）

书籍表books：(book_id,book_name,book_price,book_publisher,book_num<库存>)

订单分为订单表和订单细节表：

orders(order_id,user_id,order_total<定价总价>,order_time(下订单时间))

orderdetails(order_id,book_id,book_num)

对应上述实体表，有对应的Bean，以及各自的service类

package com.bobo.domain;

import java.io.Serializable;

public class BookBean implements Serializable{
    private int book_id;
    private String book_name;
    private int book_price;
    private String book_publisher;
    private int book_num;//库存量
    private int shoping_num=;//购买量

    public int getShoping_num() {
        return shoping_num;
    }
    public void setShoping_num(int shoping_num) {
        this.shoping_num = shoping_num;
    }
    @Override
    public String toString() {
        return "Book [book_id=" + book_id + ", book_name=" + book_name
                + ", book_price=" + book_price + ", book_publisher="
                + book_publisher + ", book_num=" + book_num + "]";
    }
    public BookBean(){

    }

    public BookBean(int book_id, String book_name, int book_price,
            String book_publisher, int book_num) {
        super();
        this.book_id = book_id;
        this.book_name = book_name;
        this.book_price = book_price;
        this.book_publisher = book_publisher;
        this.book_num = book_num;
    }

    public int getBook_id() {
        return book_id;
    }
    public void setBook_id(int book_id) {
        this.book_id = book_id;
    }
    public String getBook_name() {
        return book_name;
    }
    public void setBook_name(String book_name) {
        this.book_name = book_name;
    }
    public int getBook_price() {
        return book_price;
    }
    public void setBook_price(int book_price) {
        this.book_price = book_price;
    }
    public String getBook_publisher() {
        return book_publisher;
    }
    public void setBook_publisher(String book_publisher) {
        this.book_publisher = book_publisher;
    }
    public int getBook_num() {
        return book_num;
    }
    public void setBook_num(int book_num) {
        this.book_num = book_num;
    }

}

BookBean

package com.bobo.domain;

import java.io.Serializable;

public class UserBean implements Serializable{
    private int user_id;
    private String user_name;
    private String user_pwd;

    public UserBean(){

    }
    public UserBean(String user_name, String user_pwd) {
        super();
        this.user_name = user_name;
        this.user_pwd = user_pwd;
    }
    private String user_tel;
    private String user_email;
    private int user_grade;
    @Override
    public String toString() {
        return "User [user_id=" + user_id + ", user_name=" + user_name
                + ", user_pwd=" + user_pwd + ", user_tel=" + user_tel
                + ", user_email=" + user_email + ", user_grade=" + user_grade
                + "]";
    }
    public int getUser_id() {
        return user_id;
    }
    public void setUser_id(int user_id) {
        this.user_id = user_id;
    }
    public String getUser_name() {
        return user_name;
    }
    public void setUser_name(String user_name) {
        this.user_name = user_name;
    }
    public String getUser_pwd() {
        return user_pwd;
    }
    public void setUser_pwd(String user_pwd) {
        this.user_pwd = user_pwd;
    }
    public String getUser_tel() {
        return user_tel;
    }
    public void setUser_tel(String user_tel) {
        this.user_tel = user_tel;
    }
    public String getUser_email() {
        return user_email;
    }
    public void setUser_email(String user_email) {
        this.user_email = user_email;
    }
    public int getUser_grade() {
        return user_grade;
    }
    public void setUser_grade(int user_grade) {
        this.user_grade = user_grade;
    }

}

UserBean

package com.bobo.service;

import com.bobo.domain.BookBean;
import com.bobo.utils.SqlHelper;

import java.util.ArrayList;

public class BookService {
    /**
     * 根据id返回对应的书籍
     * @param id 书籍id
     * @return
     */
    public BookBean getBookById(int id) {
        String sqltext = "select * from books where book_id=?";
        String[] params = { id + "" };
        try {
            ArrayList<Object[]> sqlResult = SqlHelper.ExecuteReader(sqltext,
                    params);
            if (sqlResult.size() == ) {
                Object[] currentRow = sqlResult.get();
                BookBean book = new BookBean(Integer.parseInt(currentRow[]
                        + ""), currentRow[] + "",
                        Integer.parseInt(currentRow[] + ""), currentRow[]
                                + "", Integer.parseInt(currentRow[] + ""));
                return book;

            }
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
            return null;
        }
        return null;

    }

    public ArrayList<BookBean> getAllBooks() {
        ArrayList<BookBean> books = new ArrayList<BookBean>();
        String sqlText = "select * from books";
        try {
            ArrayList<Object[]> sqlResult = SqlHelper.ExecuteReader(sqlText,
                    null);
            Object[] currentRow = null;
            for (int i = ; i < sqlResult.size(); i++) {
                currentRow = sqlResult.get(i);

                BookBean book = new BookBean(Integer.parseInt(currentRow[]
                        + ""), currentRow[] + "",
                        Integer.parseInt(currentRow[] + ""), currentRow[]
                                + "", Integer.parseInt(currentRow[] + ""));
                books.add(book);

            }
            return books;
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
            return null;
        }

    }

}

BookService

package com.bobo.service;

import java.util.ArrayList;

import com.bobo.domain.UserBean;
import com.bobo.utils.SqlHelper;

//处理和user表相关的业务逻辑
public class UserService {
    /**
     * 检查该用户是否存在，如果存在，返回true，否则返回false
     * @param user 传入的用户对象，同时也通过参数传递，返回用户的其他相关信息
     * @return
     */
    public boolean checkUser(UserBean user){
        String sqlText="select * from users where user_name=? and user_pwd=?";
        String[] params={user.getUser_name(),user.getUser_pwd()};
        ArrayList<Object[]> result;
        try {
            result = SqlHelper.ExecuteReader(sqlText, params);
            if(result==null || result.size()==){
                return false;

            }else{
                //通过参数来进行传递
                Object[] temp=result.get();
                 user.setUser_id(Integer.parseInt(temp[]+""));
                 user.setUser_name(temp[]+"");
                 user.setUser_pwd(temp[]+"");
                 user.setUser_email(temp[]+"");
                 user.setUser_tel(temp[]+"");
                 user.setUser_grade(Integer.parseInt(temp[]+""));
                 return true;

            }
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
            return false;
        }

    }
}

UserService

package com.bobo.service;
import com.bobo.utils.DateHelper;
import com.bobo.utils.SqlHelper;
import com.bobo.domain.BookBean;
import com.bobo.domain.UserBean;

public class OrderService {
    private DateHelper dateHelper=new DateHelper();

    /*
     * 处理提价订单的业务逻辑
     */
    public void submitOrder(ShopingCart myCart,UserBean user){
        String dateTime=dateHelper.getCurrentTime();
        String sqlText="insert into orders (user_id,order_total,order_time) values(?,?,?)";
        String[] params={user.getUser_id()+"",myCart.getTotalPrice()+"",dateTime};
        try {
            int key=SqlHelper.ExecuteInsertReturnKey(sqlText, params);
            System.out.println("插入记录的key值是"+key);
            for(int i=;i<myCart.getCartBooks().size();i++){
                BookBean book=myCart.getCartBooks().get(i);
                sqlText="insert into orderDetails (order_id,book_id,shopping_num,order_price) values (?,?,?,?)";
                int price=book.getBook_price()*book.getShoping_num();
                String[] pars={key+"",book.getBook_id()+"",book.getShoping_num()+"", price+""};
                //这种每一次插入都需要连接打开和关闭，显然是不太好的
                SqlHelper.ExecuteNonQuery(sqlText, pars);
            }
        } catch (Exception e) {

            e.printStackTrace();
        }
    }

}

orderService

除了上述实体表对应的bean和Service之外，还有一个内存中的实体对象：购物车；数据库中并没有购物车这张表，而是利用内存中的一个hashmap来实现

package com.bobo.service;
import com.bobo.domain.*;

import java.util.ArrayList;
import java.util.HashMap;

//代表我的购物车
//在本案例中，购物车对应内存中的hashmap，而非一张实际表

public class ShopingCart {
        HashMap<Integer,BookBean> cart=new HashMap<Integer,BookBean>();

        public void addBook(Integer id){

            if(cart.containsKey(id)){
                BookBean book=cart.get(id);
                int num=book.getShoping_num();
                book.setShoping_num(num+);
                cart.put(id, book);
            }else{
                BookBean book=new BookService().getBookById(id);
                cart.put(id, book);
            }

        }
        /*//添加书
        public void addBook(Integer id,BookBean book){
            if(cart.containsKey(id)){
                int num=book.getShoping_num();
                book.setShoping_num(num+1);
                cart.put(id, book);
            }else{
                cart.put(id, book);

            }
        }*/
        @Override
        public String toString() {
            String result="";
            for(int i=;i<cart.size();i++){
                result+="book"+i+":"+cart.get(i).toString()+";";
            }
            return result;
        }
        //删除书
        public void delBook(Integer id ){
            int temp=cart.get(id).getShoping_num();
            if(temp<=){
                cart.remove(id);
            }else{
                cart.get(id).setShoping_num(temp-);
            }

        }
        //清空书
        public void clearCart(){
            cart.clear();
        }
        //更新某本书的数量
        public void updateBook(int book_id,int book_num){
            BookBean book=cart.get(book_id);
            book.setShoping_num(book_num);

        }
        //得到购物车中的所有书
        public ArrayList<BookBean> getCartBooks(){
            ArrayList<BookBean> result=new ArrayList<BookBean>();
            for(Integer id:cart.keySet()){
                result.add(cart.get(id));
            }
            return result;
        }

        //获取购物车中物品的总价
        public int getTotalPrice(){
            int result=;
            for(int id :cart.keySet()){
                result+=cart.get(id).getBook_price()*cart.get(id).getShoping_num();

            }
            return result;
        }

}

ShopingCart

四、顺着页面流和处理逻辑，来看一下整个工程吧

  r

整个工程的结构如上图所示，其中所有的jsp文件都放置在WEB-INF目录下，放置暴露给用户，仅在根目录下放置一个index.jsp作为入口，其核心是依旧jsp:forward语句，

1）具体如下：

<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>

<!DOCTYPE >
<html lang="zh-hans">
<head>
<meta charset="utf-8">
<meta name="viewport"
    content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<link rel="stylesheet" href="lib/bootstrap/css/bootstrap.min.css">
<link rel="stylesheet" href="lib/bootstrap/css/animate.min.css">
<link rel="stylesheet" href="css/login.css">
<title>用户登录页面</title>
</head>

  <body>
     <jsp:forward page="/WEB-INF/login.jsp"></jsp:forward>
  </body>
</html>

index.jsp

2）上述forward语句，将工程转到登录页面login.jsp内容如下

<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>

<!DOCTYPE >
<html lang="zh-hans">
<head>
<meta charset="utf-8">
<meta name="viewport"
    content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<link rel="stylesheet" href="mylib/bootstrap/css/bootstrap.min.css">

<link rel="stylesheet" href="css/login.css">
<title>用户登录页面</title>
</head>

<body>

    <div class="login_div">
        <h1 class="text-center">用户登录</h1>
        <form class="form-horizontal" role="form" method="post" action="/Myshoping/GoHallUI">
            <div class="form-group">
                <label for="firstname" class="col-sm-2 control-label">用户名</label>
                <div class="col-sm-10">
                    <input type="text" class="form-control" name="username"
                        placeholder="请输入用户名">
                </div>
            </div>
            <div class="form-group">
                <label for="lastname" class="col-sm-2 control-label">密码</label>
                <div class="col-sm-10">
                    <input type="text" class="form-control" name="password"
                        placeholder="请输入密码">
                </div>
            </div>
            <div class="form-group">
                <div class="row">
                <div class="col-sm-offset-1 col-sm-5">
                    <button type="submit" class="btn btn-default" id="btn_button">登录</button>
                </div>
                <div class="col-sm-offset-1 col-sm-5">
                    <button type="submit" class="btn btn-default" id="btn_button">登录</button>
                </div>
                </div>
            </div>
        </form>
    </div>

</body>
</html>

login.jsp

login.jsp呈现登录表单，要求用户输入用户名和密码

3)用户如果合法，下一步将跳转到购物大厅页面（hall.jsp）,其中，对用户身份的验证将由GoHallUIServlet来完成

package com.bobo.controller;

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

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

import com.bobo.domain.BookBean;
import com.bobo.domain.UserBean;
import com.bobo.service.BookService;
import com.bobo.service.ShopingCart;
import com.bobo.service.UserService;

public class GoHallUI extends HttpServlet {

    /**
     * The doGet method of the servlet. <br>
     *
     * This method is called when a form has its tag value method equals to get.
     *
     * @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 {
        request.setCharacterEncoding("utf-8");
        response.setContentType("text/html;charset=utf-8");
        response.setCharacterEncoding("utf-8");
        //判断用户是否已经登录（用户可能登录后，从其他页面进入购物大厅）
        if(request.getSession().getAttribute("loginUser")!=null){
            //说明用户已经登录过了,此时就不用为用户新建购物车了
            System.out.println("说明用户已经登录过了,此时就不用为用户新建购物车了");
            BookService bookService=new BookService();
            ArrayList<BookBean> bookList=bookService.getAllBooks();
            request.setAttribute("books",bookList );
            request.getRequestDispatcher("/WEB-INF/hall.jsp").forward(request, response);
            return;
        }
        //获得从登陆页面传递的用户名和密码
        String user_name=request.getParameter("username");
        String user_pwd=request.getParameter("password");
        UserBean login_user=new UserBean(user_name,user_pwd);
        //第一次成功登陆后，将用户放置到session中
        request.getSession().setAttribute("loginUser", login_user);
        UserService userService=new UserService();
        if(userService.checkUser(login_user)){
            //如果用户合法，那么跳转到购物大厅
            //用户登录成功后，为其创建购物车
            System.out.println("用户首次合法登录");
            ShopingCart cart=new ShopingCart();
            request.getSession().setAttribute("cart", cart);
            //同时为购物大厅准备好书籍数据（之所以这么设计，是为了保证如果用户不经过登录直接跳转到购物大厅，是看不到任何数据的）
            BookService bookService=new BookService();
            ArrayList<BookBean> bookList=bookService.getAllBooks();
            request.setAttribute("books",bookList );
            request.getRequestDispatcher("/WEB-INF/hall.jsp").forward(request, response);
        }else{
            //如果不合法，返回登陆页面
            System.out.println("用户非法登录");
            request.getRequestDispatcher("/WEB-INF/login.jsp").forward(request, response);

        }

    }

    /**
     * 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 {
        doGet(request,response);
    }

}

GoHallUIServlet

GoHallUIServlet主要完成以下工作：

a.如果是由登录页面跳转来的，验证用户的身份合法性（如果合法，那么将用户信息放置到session中，同时为用户创建一个购物车，将其也放置到session中）

b.如果是有其他页面想要跳转至购物大厅，那么检验session中是否有此用户信息

c.准备购物大厅要呈现的书籍数据

4)购物大厅页面，向用户呈现书籍信息，并提供购买入口

<%@ page language="java"
    import="java.util.*,java.util.ArrayList,com.bobo.domain.BookBean "
    pageEncoding="utf-8"%>

<!DOCTYPE >
<html lang="zh-hans">
<head>
<meta charset="utf-8">
<meta name="viewport"
    content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<link rel="stylesheet" href="mylib/bootstrap/css/bootstrap.min.css">
<link rel="stylesheet" href="css/hall.css">
<title>购物大厅</title>
</head>

<body>
    <div class="container">
        <h1 class="text-center">欢迎进入购物大厅</h1>
        <table>
            <%
                ArrayList<BookBean> books = (ArrayList<BookBean>) request
                        .getAttribute("books");
            %>
            <tr>
                <td>书名</td>
                <td>价格</td>
                <td>出版社</td>
                <td>点击购买</td>
            </tr>
            <%
                for (int i = ; i < books.size(); i++) {

            %>
            <tr>
                <td><%=books.get(i).getBook_name()%></td>
                <td><%=books.get(i).getBook_price()%></td>
                <td><%=books.get(i).getBook_publisher()%></td>
                <td><a href="/Myshoping/ShoppingClServlet?type=add&id=<%=books.get(i).getBook_id()%>">购买</a></td>
            </tr>
            <%
                }
            %>
        </table>
        <div>
            <button type="button" id="showCart">查看购物车</button>
            <a href="/Myshoping/index.jsp">返回重新登录</a>
        </div>
    </div>

</body>
</html>

hall.jsp

5）用户的购买行为记录在购物车中（这不是一个数据库中的对象，用一个内存中hashmap来表示）；用户在hall.jsp页面的购买请求，经过ShopingClServlet处理之后，在跳转至购物车页面（用户操作购物车的行为可能有多种，因此使用额外的参数type来记录究竟是哪一种行为）

package com.bobo.controller;

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

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

import com.bobo.service.BookService;
import com.bobo.service.ShopingCart;

//该控制器用于响应用户购买商品的请求
public class ShoppingClServlet extends HttpServlet {

    /**
     * The doGet method of the servlet. <br>
     *
     * This method is called when a form has its tag value method equals to get.
     *
     * @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 {

        doPost(request, response);
    }

    /**
     * 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=utf-8");
        request.setCharacterEncoding("utf-8");
        response.setCharacterEncoding("utf-8");
        ShopingCart cart = (ShopingCart) request.getSession().getAttribute(
                "cart");
        String type = request.getParameter("type");
        if (type.equals("add")) {
            // 从购物大厅页面接受用户的购买请求，准备数据，跳转到购物车页面
            int book_id = Integer.parseInt(request.getParameter("id"));
            cart.addBook(book_id);            

        } else if (type.equals("delete")) {
            // 从购物车页面接受用户的删除请求，准备数据，再跳转到购物车页面,但是怎么判断是从哪个页面跳转来的呢
            int del_id = Integer.parseInt(request.getParameter("del_id"));
            System.out.println(del_id);
            cart.delBook(del_id);
        }else if(type.equals("update")){
            //如果是数量的更新操作，注意每一行都有一个id和对应的数量，因此获得的是一个数组
            String[] book_ids=request.getParameterValues("id");
            String[] book_nums=request.getParameterValues("book_num");    

            //去购物车业务类中进行更新
            for(int i=;i<book_ids.length;i++){
                cart.updateBook(Integer.parseInt(book_ids[i]), Integer.parseInt(book_nums[i]));
            }

        }
        request.setAttribute("totalPrice", cart.getTotalPrice());
        request.setAttribute("cartBooks", cart.getCartBooks());
        System.out.println(cart.getCartBooks());
        request.getRequestDispatcher("/WEB-INF/showMyCart.jsp").forward(
                request, response);

    }

}

shopingClServlet

该页面的处理用户对于购物车的各种行为，包括购买，删除和数量更新，处理之后，跳转好购物车页面showMyCart.jsp

6)在showMyCart.jsp中，用户可以对购物车中的书籍进行删除和数量更新，这些请求，也将由shopingClServlet来处理

<%@ page language="java" import="java.util.*,com.bobo.domain.BookBean"
    pageEncoding="utf-8"%>

<!DOCTYPE >
<html lang="zh-hans">
<head>
<meta charset="utf-8">
<meta name="viewport"
    content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<link rel="stylesheet" href="mylib/bootstrap/css/bootstrap.min.css">
<link rel="stylesheet" href="css/showMyCart.css">
<title>我的购物车</title>
</head>

<body>
    <div class="container">
        <h1 class="text-center">我的购物车</h1>
        <form action="ShoppingClServlet?type=update" method="post">
            <table>
                <tr>
                    <td>book_id</td>
                    <td>书名</td>
                    <td>价格</td>
                    <td>出版社</td>
                    <td>数量</td>
                    <td>删除</td>
                </tr>
                <%
                    ArrayList<BookBean> list = (ArrayList<BookBean>) request
                            .getAttribute("cartBooks");
                    for(int i=;i<list.size();i++){
                    BookBean book=list.get(i);
                %>
                <tr>
                    <!-- 使用隐藏的表单来传递内容 -->
                    <td><%=book.getBook_id() %><input type="hidden" value=<%=book.getBook_id() %> name="id"></td>
                    <td><%=book.getBook_name() %></td>
                    <td><%=book.getBook_price()%></td>
                    <td><%=book.getBook_publisher()%></td>
                    <td><input type="text" name="book_num" value=<%=book.getShoping_num() %>></input></td>
                    <td><a href="/Myshoping/ShoppingClServlet?type=delete&del_id=<%=book.getBook_id()%>">删除</a></td>
                </tr>
                <%} %>
                <tr>
                    <td colspan=""><input type="submit" value="update"/></td>
                </tr>
            </table>
            </form>
            <div>
                <p>商品总价是: ${totalPrice} 元</p>
            </div>
            <p>
                <a href="/Myshoping/GoMyOrder">提交订单</a>
                <a href="/Myshoping/GoHallUI">返回购物大厅</a>
            </p>
        </form>
    </div>

</body>
</html>

showMyCart.jsp

7)最终，如果用户确定购买，点击购物车页面“确认订单”页面后，将由GoMyOrderServlet将订单信息记录到数据库中，然后跳转至订单成功页面

package com.bobo.controller;

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

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

import com.bobo.domain.BookBean;
import com.bobo.domain.UserBean;
import com.bobo.service.ShopingCart;
//处理用户查看订单的请求
public class GoMyOrder extends HttpServlet {

    /**
     * The doGet method of the servlet. <br>
     *
     * This method is called when a form has its tag value method equals to get.
     *
     * @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 {
        request.setCharacterEncoding("utf-8");
        response.setCharacterEncoding("utf-8");
        response.setContentType("text/html");
        PrintWriter out = response.getWriter();
        //为订单查看页面准备用户信息，和订单信息
        ShopingCart cart=(ShopingCart) request.getSession().getAttribute("cart");
        ArrayList<BookBean> books=cart.getCartBooks();
        request.setAttribute("books", books);
        int total_price=cart.getTotalPrice();
        request.setAttribute("total_price", total_price);
        UserBean user=(UserBean)request.getSession().getAttribute("loginUser");
        request.setAttribute("loginUser", user);
        request.getRequestDispatcher("/WEB-INF/myOrder.jsp").forward(request, response);

    }

    /**
     * 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 {

         doGet(request,response);
    }

}

GoMyOrderServlet

订单的插入操作涉及两张表，订单表和订单详情表，其中要注意，在向订单表中插入一条新订单，数据库自动生成一条订单id后，在向订单详情表中插入详情后，这里的订单id一定要是上面生成的id，因此要注意数据库操作的事务性。

8）最终的订单ok页面（邮件的发送暂时没有做）

<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>

<title>订单已提交</title>

<meta charset="utf-8">
<meta name="viewport"
    content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<!--
    <link rel="stylesheet" type="text/css" href="styles.css">
    -->

</head>

<body>
    <h2>订单已经提交，邮件已发送至您的注册邮箱，请至邮箱确认！</h2>
</body>
</html>

OrderOK.jsp

其他：此外，该项目中，自己实现了两个listener

1）ServletContextEvent

在本例中的功能是每隔一段时间打印一段日志，在实际项目中，可以用于应用启动的时候获取数据库的参数，以及定时备份等

package com.bobo.listener;

import javax.servlet.ServletContextEvent;
import java.util.Timer;
import java.util.TimerTask;

import javax.servlet.ServletContextListener;
/*
 * 这个类用于监听整个web应用的启动和销毁，可以用于执行某些定时程序，获得数据库的连接等，有点类似于on-start:1的servlet
 * */

public class ContextListener implements ServletContextListener {
private Timer timer;
    @Override
    public void contextDestroyed(ServletContextEvent arg0) {
        timer.cancel();

    }

    @Override
    public void contextInitialized(ServletContextEvent arg0) {
        // TODO Auto-generated method stub

         timer=new Timer();
            timer.schedule(new TimerTask(){

                @Override
                public void run() {
                    System.out.println("定时器正常工作");

                }

            }, *);
    }

}

ServletContextEvent

1）ServletContextEvent

在本例中的功能是每隔一段时间打印一段日志，在实际项目中，可以用于应用启动的时候获取数据库的参数，以及定时