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欢迎来到Jsp编程课时十二——今天实现的目标是。@1将数据库的数据发送到浏览器。@2利用浏览器实现对数据库的增删改查操作。@3理解MVC三层架构的定义。（二）

2023-07-14 53
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简介： 欢迎来到Jsp编程课时十二——今天实现的目标是。@1将数据库的数据发送到浏览器。@2利用浏览器实现对数据库的增删改查操作。@3理解MVC三层架构的定义。（二）

后端代码区第一部分

package com.DengLu.And.Zhu.Ce;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Random;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
 * Servlet implementation class ServlectDengLuLogic
 */
@WebServlet("/ServlectDengLuLogic")
public class ServlectDengLuLogic extends HttpServlet {
  private static final long serialVersionUID = 1L;
    /**
     * @see HttpServlet#HttpServlet()
     */
    public ServlectDengLuLogic() {
        super();
        // TODO Auto-generated constructor stub
    }
  /**
   * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
   */
  protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    // TODO Auto-generated method stub
  }
  /**
   * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
   */
  protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    /**
     * do--post
     */
     response.setContentType("text/html");
     response.setCharacterEncoding("UTF-8");
    ServletContext  sc=getServletContext();
    //获取web.xml文件中的镜头数据
    String a=sc.getInitParameter("QQ");
    String b=sc.getInitParameter("PSD");
    String c=sc.getInitParameter("USER");
    System.out.println(a+"@@@@@@@@"+b);
     response.getWriter().append("ServletB获得静态数据用来访问web.xml"+a);
     String aa=request.getParameter("qq");
     String bb=request.getParameter("psd");
     String cc=request.getParameter("user");
      //不区分大小写equalsIgnoreCase(aa)
      if(a.equalsIgnoreCase(aa)&&b.equalsIgnoreCase(bb)&&c.equalsIgnoreCase(cc)) {
        //重定向跳转页面
        System.out.println("登录成功跳转到2021登录成功");
        response.sendRedirect("HomeServlet");
        /* response.setHeader("refresh","60;URL=Register.jsp"); */
      }else {
        System.out.println("登录失败五秒后返回Register.jsp");
        /* response.sendRedirect("Register.jsp"); */
        response.setHeader("refresh","3;URL=Register.jsp");
      }
  }
}
package com.DengLu.And.Zhu.Ce;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
 * Servlet implementation class ServlectDengLuLose
 */
@WebServlet("/DengLuChengGong")
public class ServlectDengLuLose extends HttpServlet {
  private static final long serialVersionUID = 1L;
    /**
     * @see HttpServlet#HttpServlet()
     */
    public ServlectDengLuLose() {
        super();
        // TODO Auto-generated constructor stub
    }
  /**
   * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
   */
  protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    response.setContentType("text/html");
    response.setCharacterEncoding("utf-8");
    PrintWriter pw = response.getWriter();
    pw.append("60秒后回到ZhuCe.jsp");
    response.setHeader("refresh","60;URL=ZhuCe.jsp");
  }
  /**
   * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
   */
  protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    // TODO Auto-generated method stub
    doGet(request, response);
  }
}
package com.DengLu.And.Zhu.Ce;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Random;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
 * Servlet implementation class ServlectDengLuLogic
 */
@WebServlet("/ServlectZhuCe")
public class ServlectZhuCe extends HttpServlet {
  private static final long serialVersionUID = 1L;
    /**
     * @see HttpServlet#HttpServlet()
     */
    public ServlectZhuCe() {
        super();
        // TODO Auto-generated constructor stub
    }
  /**
   * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
   */
  protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    // TODO Auto-generated method stub
  }
  /**
   * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
   */
  protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    /**
     * do--post
     */
     response.setContentType("text/html");
     response.setCharacterEncoding("UTF-8");
    ServletContext  sc=getServletContext();
    //获取web.xml文件中的镜头数据
    String a=sc.getInitParameter("USER");
    String b=sc.getInitParameter("QQ");
    String c=sc.getInitParameter("PSD");
    String d=sc.getInitParameter("SJ");
    String  e=sc.getInitParameter("HOME");
    System.out.println(a+"@@@"+b+"@@@"+c+"@@@"+d+"@@@"+e);
     response.getWriter().append("<h1>ServlectZhuCe获得静态数据用来访问web.xml</h1>");
     String aa=request.getParameter("user");
     String bb=request.getParameter("qq");
     String  cc=request.getParameter("psd");
     String dd=request.getParameter("sj");
     String ee=request.getParameter("home");
      //不区分大小写equalsIgnoreCase(aa)
      if(a.equalsIgnoreCase(aa)&&b.equalsIgnoreCase(bb)&&c.equalsIgnoreCase(cc)&&d.equalsIgnoreCase(dd)&&e.equalsIgnoreCase(ee)) {
        //重定向跳转页面
        System.out.println("注册成功跳转到2021登录成功");
        response.sendRedirect("Login.jsp");
        /* response.setHeader("refresh","60;URL=Register.jsp"); */
      }else {
        System.out.println("注册失败五秒后返回Register.jsp");
        /* response.sendRedirect("Register.jsp"); */
        response.setHeader("refresh","8;URL=ZhuCeLose");
      }
  }
}
package com.DengLu.And.Zhu.Ce;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Random;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
 * Servlet implementation class ServlectDengLuLose
 */
@WebServlet("/ZhuCeLose")
public class ZhuCeLose extends HttpServlet {
  private static final long serialVersionUID = 1L;
    /**
     * @see HttpServlet#HttpServlet()
     */
    public ZhuCeLose() {
        super();
        // TODO Auto-generated constructor stub
    }
  /**
   * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
   */
  protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    response.setCharacterEncoding("UTF-8");
    response.setContentType("text/html");
    response.setHeader("refresh", "5");
    //设置要求浏览器 
    /* response.sendRedirect("Servlet1"); */
    int i=(int)(Math.random()*900000+100000);
    int a=(int)(Math.random()*9000+1000);
    int c=(int)(Math.random()*900+100);
    System.out.println("@@@@"+(new Random().nextInt(900000)+100000));
    /*
     * 设置随机
     */
    System.out.println(new Random().nextInt(100));
    System.out.println(Math.random());
    PrintWriter  pw =response.getWriter();
    pw.print("你的支付宝到账1000万元，需要的码号为:<h1 style='color:red ;background-color:green'>"+i+"</h1>,打死也不说  \"<hr>\";");
    pw.print("你的QQ到账1000万元，需要的码号为:<h2 style='color:red ;background-color:green'>"+c+"</h2>,打死也不说   \"<hr>\";");
    pw.print("你的微信到账1000万元，需要的码号为:<span style='color:green'>"+a+"</span>,打死也不说"); 
    pw.print("你的手机支付宝到账1000万<span style='color :red'>"+i+"</span>");
    pw.append("<style>");
    pw.append(" *{\r\n" + 
        "            margin: 0px;\r\n" + 
        "            padding: 0px;\r\n" + 
        "            background: white;\r\n" + 
        "            font-size: 30px;\r\n" + 
        "            font-weight: bold;\r\n" + 
        "            text-shadow: 1px 1px 1px red;\r\n" + 
        "\r\n" + 
        "        }");
    pw.append("</style>");
    pw.append("<h1 align ='center'>2021你年垮2022年QQ登陆失败的界面</h1>");
    pw.append("注册界面失败请重新注册");
    response.setHeader("refresh","5;URL=Register.jsp");
    pw.append("<h2 align ='center'><a href='Register.jsp'>点击这里返回注册界面进行重新注册</a></h2>");
    pw.append("如果用户一分钟后没有任何操作则在60秒后调到index.jsp文件");
    response.setHeader("refresh","30;URL=index.jsp");
  }
  /**
   * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
   */
  protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    // TODO Auto-generated method stub
    doGet(request, response);
  }
}

后端代码第二部分

package com.entity;
/**
 * 
 * 图书实体类
 * @author MZFAITHDREAM
 * 2021/10/19
 *
 */
public class Book {
   private String bookName;  //书名
   private  String autor;   //作者
   private  String price;
   private  String address;//出版社
   private  String buyTime;   //图书时间
  //生成get set方法
  //null构造方法 创建对象 在创建对象
   //toString
  public Book() {
    // TODO Auto-generated constructor stub
  }
  public Book(String bookName, String autor, String price, String address, String buyTime) {
    super();
    this.bookName = bookName;
    this.autor = autor;
    this.price = price;
    this.address = address;
    this.buyTime = buyTime;
  }
  public String getBookName() {
    return bookName;
  }
  public void setBookName(String bookName) {
    this.bookName = bookName;
  }
  public String getAutor() {
    return autor;
  }
  public void setAutor(String autor) {
    this.autor = autor;
  }
  public String getPrice() {
    return price;
  }
  public void setPrice(String price) {
    this.price = price;
  }
  public String getAddress() {
    return address;
  }
  public void setAddress(String address) {
    this.address = address;
  }
  public String getBuyTime() {
    return buyTime;
  }
  public void setBuyTime(String buyTime) {
    this.buyTime = buyTime;
  }
  @Override
  public String toString() {
    return "Book [bookName=" + bookName + ", autor=" + autor + ", price=" + price + ", address=" + address
        + ", buyTime=" + buyTime + "]";
  }
}
package com.Filter;
import java.io.IOException;
import java.io.OutputStream;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
public class MyFilter4 implements Filter{
  public MyFilter4() {
    // TODO Auto-generated constructor
    System.out.println("我创建了第一个MyFilter过滤器");
  }
  @Override
  public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
      throws IOException, ServletException {
      response.setContentType("text/html");
      response.setCharacterEncoding("UTF-8"); 
      System.out.println("我是myfilter开始拦截请求地址哦哦");
  }
  @Override
  public void init(FilterConfig config) throws ServletException {
    // TODO Auto-generated method stub
    System.out.println("FilterConfig用来加载初始化数据");
  }
  @Override
  public void destroy() {
    System.out.println("Filter所有方法运行完毕后销毁过滤器");
  }
}
package com.Listener;
/**
 * 第三类接口
 */
import javax.servlet.http.HttpSessionBindingEvent;
import javax.servlet.http.HttpSessionBindingListener;
public class Listener  implements   HttpSessionBindingListener {
    private int id;
      private String username;
      private String password;
      public Listener() {
      // TODO Auto-generated constructor stub
    }
  public Listener(int id, String username, String password) {
      super();
      this.id = id;
      this.username = username;
      this.password = password;
    }
  public int getId() {
    return id;
  }
  public void setId(int id) {
    this.id = id;
  }
  public String getUsername() {
    return username;
  }
  public void setUsername(String username) {
    this.username = username;
  }
  public String getPassword() {
    return password;
  }
  public void setPassword(String password) {
    this.password = password;
  }
  @Override
  public String toString() {
    return "Listener [id=" + id + ", username=" + username + ", password=" + password + ", getId()=" + getId()
        + ", getUsername()=" + getUsername() + ", getPassword()=" + getPassword() + ", getClass()=" + getClass()
        + ", hashCode()=" + hashCode() + ", toString()=" + super.toString() + "]";
  }
  @Override
  public void valueBound(HttpSessionBindingEvent event) {
    // TODO Auto-generated method stub
     System.out.println("HttpSession 与 Listener绑定");
    HttpSessionBindingListener.super.valueBound(event);
  }
  @Override
  public void valueUnbound(HttpSessionBindingEvent event) {
    // TODO Auto-generated method stub
     System.out.println("HttpSession 与 Listener解绑绑");
    HttpSessionBindingListener.super.valueUnbound(event);
  }
}
package com.Servlect;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
 * Servlet implementation class HomeServlect2
 */
@WebServlet("/HomeServlect2")
public class HomeServlect2 extends HttpServlet {
  private static final long serialVersionUID = 1L;
    /**
     * @see HttpServlet#HttpServlet()
     */
    public HomeServlect2() {
        super();
        // TODO Auto-generated constructor stub
    }
  /**
   * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
   */
  protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    // TODO Auto-generated method stub
    //response.getWriter().append("Served at: ").append(request.getContextPath());
    response.setContentType("text/html");
    response.setCharacterEncoding("UTF-8");
    PrintWriter pw =response.getWriter();
    pw.append("<h1 style='color:red'>登录成功</h1>");
    pw.append("<h2>本案例运用的对象\r\n" + 
        "<hr>\r\n" + 
        "ServletConfig：对象获得静态数据\r\n" + 
        "<hr>\r\n" + 
        "ServletContext对象：获取共享静态数据，获取共享动态数据，获取共享文件数据.\r\n" + 
        "<hr>\r\n" + 
        "HttpServletResponse 对象HttpServlet调用HttpResponse的有关方法，生成响应数据\r\n" + 
        "<hr>\r\n" + 
        "HttpServletRequest对象：HttpServlet调用HttpResponse的有关方法，生成响应数据,用于服务器上接收浏览器发送过来的数据信息\r\n" + 
        "<hr>\r\n" + 
        "Cookie对象,对象Session对象。程序把每个用户的数据以Cookie/Session的形式写给用户各自的浏览器。\r\n" + 
        "<hr>\r\n" + 
        "Filter:过滤器，阻止非法网站的访问。\r\n" + 
        "<hr>\r\n" + 
        "Listener:\r\n" + 
        "实现了特定接口的类为监听器，用来监听另一个Java类的方法调用或者属性改变；** 当被监听的对象发生了方法调用或者属性改变后，\r\n" + 
        "监听器的对应方法就会立即执行.\r\n" + 
        "<hr>\r\n" + 
        "九大内置对象的核心表格\r\n" + 
        "<hr>\r\n" + 
        "out         JspWriter    将文本信息输出浏览器\r\n" + 
        "<hr>\r\n" + 
        "request  HttpServletRequest   获得浏览器发送来的数据\r\n" + 
        "<hr>\r\n" + 
        "respone   HttpServletRequest   回复浏览器请求\r\n" + 
        "<hr>\r\n" + 
        "seesion  HttpSeesion           在不换浏览器放信息\r\n" + 
        "<hr>    \r\n" + 
        "exception  Throwable    异常报错\r\n" + 
        "<hr>\r\n" + 
        "page Servlect(this)    jsp翻译出来类的对象\r\n" + 
        "<hr>\r\n" + 
        "config     ServlectConfig            静态数据\r\n" + 
        "<hr>\r\n" + 
        "application  ServlectContext    共享数据\r\n" + 
        "<hr>\r\n" + 
        "pageContext   PageContextjsp       管理者引出对象\r\n" + 
        "<hr>\r\n" + 
        "seesion   浏览器不切\r\n" + 
        "application  服务器不关闭\r\n" + 
        "request：请求转发跳转页面的情况，只能两个页面共享数据\r\n" + 
        "pageContext：该对象中只能页面自己用\r\n" + 
        "才能用setAttribute的方法\r\n" + 
        "将四作用域排序\r\n" + 
        "pageContext request seesion application \r\n" + 
        "</h2>");
    pw.append("<h1><a href='index.jsp'>返回主界面</a></h1>");
  }
  /**
   * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
   */
  protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    // TODO Auto-generated method stub
    doGet(request, response);
  }
}
package com.Servlect;
import java.io.IOException;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.annotation.WebFilter;
/**
 * Servlet Filter implementation class MyFilter1
 */
//你要阻止Servlect2
@WebFilter("/Servlect2")
public class MyFilter1 implements Filter {
    /**
     * Default constructor. 
     */
    public MyFilter1() {
        // TODO Auto-generated constructor stub
      System.out.println("构造方法");
    }
  /**
   * @see Filter#destroy()
   */
  public void destroy() {
    // TODO Auto-generated method stub
    System.out.println("销毁数据");
  }
  /**
   * @see Filter#doFilter(ServletRequest, ServletResponse, FilterChain)
   */
  public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
    response.setContentType("text/html");
    response.setCharacterEncoding("UTF-8");
    System.out.println("我是myfilter1开始拦截请求地址哦哦");
    //实施访问
    chain.doFilter(request, response);
  }
  /**
   * @see Filter#init(FilterConfig)
   */
  public void init(FilterConfig fConfig) throws ServletException {
    // TODO Auto-generated method stub
    System.out.println("加载数据");
  }
}
package com.Servlect;
/**
 * 这一个类让我们去了解Servlect的周期
 */
import java.io.IOException;
import javax.servlet.Servlet;
import javax.servlet.ServletConfig;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
public class ServlectOne  implements Servlet{
  public ServlectOne() {
    // TODO Auto-generated constructor stub
    System.out.println("@1 Servlec方法的构造方法");
  }
  @Override
  public void destroy() {
  System.out.println("@2 Servlect方法的销毁");
  }
  @Override
  public ServletConfig getServletConfig() {
    // TODO Auto-generated method stub
    System.out.println("@ 3Servlect方法加载静态数据");
    return null;
  }
  @Override
  public String getServletInfo() {
    // TODO Auto-generated method stub
    System.out.println("@ 4 Servlect的getServletInfo方法");
    return null;
  }
  @Override
  public void init(ServletConfig config) throws ServletException {
    // 获取静态数据的对象
    String a=config.getInitParameter("SFZ");
      System.out.println(a);
    System.out.println("@5 Servlecto的init方法");
    System.out.println("获取静态数据的对象config");
    //动态数据的获取
  }
  @Override
  public void service(ServletRequest req, ServletResponse res) throws ServletException, IOException {
    // TODO Auto-generated method stub
    System.out.println("@5 Servlecto的servlect方法");
  }
}
package com.servlet;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.entity.Book;
/**
 * Servlet implementation class AlertServlet
 */
@WebServlet("/AlertServlet")
public class AlertServlet extends HttpServlet {
  private static final long serialVersionUID = 1L;
    /**
     * @see HttpServlet#HttpServlet()
     */
    public AlertServlet() {
        super();
        // TODO Auto-generated constructor stub
    }
  /**
   * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
   */
  protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    // TODO Auto-generated method stub
    Book book=(Book) request.getAttribute("book");
    String info="<h1>当前《"+book.getBookName()+"书籍购买成功，如需需要再次购买请<a href='ShowBuyBookServlet'>点击这里</a>回到购书页面,"
        + "或者10秒之后自动跳转至首页</h1>";
    response.setContentType("text/html");
    response.setCharacterEncoding("UTF-8");
    //
    response.setHeader("refresh", "1"+"开始倒计时");
    //五秒后自动跳转到HomeServlet
    response.setHeader("refresh", "10;url=ZhuCe.jsp");
    PrintWriter pw=response.getWriter();
    pw.print(info);
  }
  /**
   * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
   */
  protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    // TODO Auto-generated method stub
    doGet(request, response);
  }
}
package com.servlet;
import java.io.IOException;
import java.sql.Connection;
import java.util.ArrayList;
import java.util.List;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.entity.Book;
import com.util.BooksDBUtil;
/**
 * Servlet implementation class GetBuyBookInfoServlet
 */
@WebServlet("/GetBuyBookInfoServlet")
public class GetBuyBookInfoServlet extends HttpServlet {
  private static final long serialVersionUID = 1L;
    /**
     * @see HttpServlet#HttpServlet()
     */
    public GetBuyBookInfoServlet() {
        super();
        // TODO Auto-generated constructor stub
    }
  /**
   * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
   */
  protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    //获得浏览器发送的下标
    String index=request.getParameter("index");
    int i=Integer.parseInt(index);
    //根据下标从书库中定位到用户要购买的是哪本书
    List<Book> oBooks=BooksDBUtil.getBooks();
    Book book=oBooks.get(i);
    //获得当前购买的实时时间
    String time=BooksDBUtil.getNowTime();
    book.setBuyTime(time);
    //存储至ServletContext对象中
    ServletContext sc=getServletContext();
    //先判断ServletContext是否有其他的购买记录
    //如果有，新的购买记录只需要添加到原有的list集合里面
    //如果没有，现在是第一次买书，ServletContext之前没有保存过购买记录，也就意味着该对象中并不存在list集合
    Object object=sc.getAttribute("orders");
    List<Book> oList=null;
    if (object==null) {
      //说明从来都没有保存过购买记录
      oList=new ArrayList<Book>();
      oList.add(book);
    }else {
      //如果以前有保存过购买记录
      oList=(List<Book>) object;
      oList.add(book);
    }
    //将更新后的list集合保存至ServletContext对象
    sc.setAttribute("orders", oList);
    //跳转至一个Servlet页面，告诉用户当前购买成功，如需再次购买请点击这里回到购书页面
    //如果Servlet之间跳转不需要携带数据，传递数据，一般使用重定向
    //否则使用请求转发
    request.setAttribute("book", book);
    request.getRequestDispatcher("AlertServlet").forward(request, response);
  }
  /**
   * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
   */
  protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    // TODO Auto-generated method stub
    doGet(request, response);
  }
}
package com.servlet;
/**
 * 浏览数据的主界面
 */
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebInitParam;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
 * Servlet implementation class HomeServlet
 */
@WebServlet(urlPatterns = "/HomeServletBook",initParams = {
    @WebInitParam(name="buyBook",value="购买图书"),
    @WebInitParam(name="selectOrder",value="查看记录"),
    //增加一个界面为手机管理
    @WebInitParam(name="buyBookA",value="购买图书A ")
})
public class HomeServletBook extends HttpServlet {
  private static final long serialVersionUID = 1L;
  String buyBook ="";
  String buyBookA ="";
  String  selectOrder="";
    /**
     * @see HttpServlet#HttpServlet()
     */
    public HomeServletBook() {
        super();
        System.out.println("HomeServlet() 在运行主界面中");
        // TODO Auto-generated constructor stub
    }
    @Override
    public void init(ServletConfig config) throws ServletException {
      super.init(config);
      //得到二个静态数据
       buyBook =config.getInitParameter("buyBook");
       buyBookA =config.getInitParameter("buyBookA");
       selectOrder =config.getInitParameter("selectOrder");
    }
  /**
   * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
   */
  protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    //当浏览器访问Servlet的组成浏览器能看到的页面
    response.setContentType("text/html");
    response.setCharacterEncoding("utf-8");
    PrintWriter pw = response.getWriter();
    pw.append("<h1 align ='center'>图书界面</h1>");
    pw.append("<div align ='center'style=' background-color: #CCFFFF;'><h1 style='color:red'>");
    pw.append("<a href='ShowBuyBookServlet'>"+ buyBook+"</a>&nbsp;&nbsp;<br>");
    pw.append("<a href='SelectOrderServlect'>"+selectOrder+"</a>&nbsp;&nbsp;<br>");
    pw.append("</h1></div>");
    System.out.println(buyBook+selectOrder);
  }
  /**
   * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
   */
  protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    // TODO Auto-generated method stub
    doGet(request, response);
  }
}
-
package com.servlet;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.List;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.entity.Book;
/**
 * Servlet implementation class SelectOrderServlect
 */
@WebServlet("/SelectOrderServlect")
public class SelectOrderServlect extends HttpServlet {
  private static final long serialVersionUID = 1L;
    /**
     * @see HttpServlet#HttpServlet()
     */
    public SelectOrderServlect() {
    }
  /**
   * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
   */
  protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
     //从servletContext对象中，获取购买图书，并把图书信息在表格中能看到
    ServletContext sc=getServletContext();
    Object object = sc.getAttribute("orders");
    response.setContentType("text/html");
    response.setCharacterEncoding("utf-8");
    PrintWriter pw = response.getWriter();
    //进行判断 ifobject为null
    if(object==null) {
      pw.print("<h1align ='center' style='color:red'>查看记录</h1>");
      pw.print("<h1>当前没有购买读书信息请购买图书信息！！！！</h1>");
    }else {
      List<Book> oBooks=(List<Book>) object;
      pw.append("<div align='center'>");
      pw.append("<table border='3' style='width:800px;text-align:center;'>");
      pw.append("<tr>");
      pw.append("<td>书名</td>");
      pw.append("<td>作者</td>");
      pw.append("<td>单价</td>");
      pw.append("<td>出版社</td>");
      pw.append("<td>购买时间</td>");
      pw.append("</tr>");
      //根据循环遍历list集合，从list集合中获得每一本图书信息
      for (int i = 0; i < oBooks.size(); i++) {
        pw.append("<tr>");
        pw.append("<td style='  background-color: lavender'>"+oBooks.get(i).getBookName()+"</td>");
        pw.append("<td style='  background-color:  lightblue'>"+oBooks.get(i).getAutor()+"</td>");
        pw.append("<td style='  background-color: pink'>"+oBooks.get(i).getPrice()+"</td>");
        pw.append("<td style='  background-color:  lightblue'>"+oBooks.get(i).getAddress()+"</td>");
        pw.append("<td>"+oBooks.get(i).getBuyTime()+"</td>");
        pw.append("</tr>");
      }
      pw.append("</table>");
      pw.append("</div>");
    }
    }
  /**
   * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
   */
  protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    // TODO Auto-generated method stub
    doGet(request, response);
  }
}
package com.servlet;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.List;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.entity.Book;
import com.util.BooksDBUtil;
/**
 * Servlet implementation class ShowBuyBookServlet
 */
@WebServlet("/ShowBuyBookServlet")
public class ShowBuyBookServlet extends HttpServlet {
  private static final long serialVersionUID = 1L;
    /**
     * @see HttpServlet#HttpServlet()
     */
    public ShowBuyBookServlet() {
        super();
        // TODO Auto-generated constructor stub
    }
  /**
   * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
   */
  protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    //从其他类中获取出要显示在浏览器上的所有图书信息
    List<Book> oBooks=BooksDBUtil.getBooks();
    response.setContentType("text/html");
    response.setCharacterEncoding("UTF-8");
    PrintWriter pw=response.getWriter();
    pw.append("<h1 align ='center' style='color:red'>手机浏览界面</h1>");
    pw.append("<div align='center'>");
    pw.append("<table border='3' style='width:800px;text-align:center;'>");
    pw.append("<tr>");
    pw.append("<td>书名</td>");
    pw.append("<td>作者 </td>");
    pw.append("<td>单价</td>");
    pw.append("<td>出版社</td>");
    pw.append("<td>操作</td>");
    pw.append("</tr>");
    //根据循环遍历list集合，从list集合中获得每一本图书信息
    for (int i = 0; i < oBooks.size(); i++) {
      pw.append("<tr>");
      pw.append("<td style='  background-color: lavender'>"+oBooks.get(i).getBookName()+"</td>");
      pw.append("<td style='  background-color:  lightblue'>"+oBooks.get(i).getAutor()+"</td>");
      pw.append("<td style='  background-color: pink'>"+oBooks.get(i).getPrice()+"</td>");
      pw.append("<td style='  background-color:  lightblue'>"+oBooks.get(i).getAddress()+"</td>");
      pw.append("<td style='  background-color: yellow'><a href='GetBuyBookInfoServlet?index="+i+"'>"
          + "<input type='button' value='购买' style='background: lightblue;width:100px'></a></td>");
      pw.append("</tr>");
    }
    pw.append("</table>");
    pw.append("</div>");
  }
  /**
   * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
   */
  protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    // TODO Auto-generated method stub
    doGet(request, response);
  }
}
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关键词：
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