JSP显示新闻

Posted Luomei

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JSP显示新闻

1、项目结构

  java:

  Web:

 

 

2、Java部分详细介绍

2.1 Controller

  • GetSessionServlet: 
  • LoginServlet:
    • 用来获取网站的登录信息,并传给UsersService进行处理判断
       1 package Controller;
       2 
       3 import Entity.Users;
       4 import Service.UsersService;
       5 import Util.CookieSave;
       6 import javax.servlet.ServletException;
       7 import javax.servlet.annotation.WebServlet;
       8 import javax.servlet.http.HttpServlet;
       9 import javax.servlet.http.HttpServletRequest;
      10 import javax.servlet.http.HttpServletResponse;
      11 import java.io.IOException;
      12 import java.sql.SQLException;
      13 
      14 @WebServlet(name = "Controller.LoginServlet")
      15 public class LoginServlet extends HttpServlet {
      16     protected void doPost(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
      17         doGet(request,response);
      18     }
      19     protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
      20         response.setContentType("text/html;charset=utf-8");
      21         request.setCharacterEncoding("utf-8");
      22         //Login的处理
      23         try {
      24             Login(request,response);
      25         } catch (SQLException e) {
      26             e.printStackTrace();
      27         }
      28     }
      29     void Login(HttpServletRequest request, HttpServletResponse response) throws IOException, SQLException {
      30         //获取表单中的数据的值
      31         Users user=new Users();
      32         user.setName(request.getParameter("username"));
      33         user.setPassword(request.getParameter("password"));
      34         System.out.println("登入用户名:"+user.getName());
      35         System.out.println("登入用户密码:"+user.getPassword());
      36         System.out.println("-------------------------------");
      37         //验证用户名密码
      38         UsersService usersService=new UsersService();
      39         boolean hasUsers=usersService.QueryUsers(user);
      40         if(hasUsers){
      41             CookieSave cookieSave=new CookieSave();
      42             cookieSave.Save(response,"username",user.getName(),60*60*24*30);
      43             cookieSave.Save(response,"password",user.getPassword(),60*60*24*30);
      44             //成功登录,进入管理主界面
      45             response.sendRedirect("yinglang/index.html");
      46         }else
      47         {
      48             response.getWriter().println("登陆失败");
      49             //登录失败,返回登陆界面
      50             response.sendRedirect("login.html");
      51         }
      52     }
      53 }
  • ShowNewsListServlet:
    • 从NewsService中获取所需的数据,并将数据传递给ShowNewsList.jsp来显示
      package Controller;
      
      import Entity.News;
      import Service.NewsService;
      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 java.io.IOException;
      import java.sql.SQLException;
      import java.util.List;
      
      @WebServlet(name = "Controller.ShowNewsListServlet")
      public class ShowNewsListServlet extends HttpServlet {
          protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
              doGet(request,response);
          }
          protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
              request.setCharacterEncoding("utf-8");
              NewsService newsService=new NewsService();
              try {
                  List<News> lsNews=newsService.QueryNews();
                  request.setAttribute("lsNews",lsNews);
                  request.getRequestDispatcher("ShowNewsList.jsp").forward(request,response);
              } catch (SQLException e) {
                  e.printStackTrace();
              }
          }
      }

2.2 DAL

  • SqlHelper
    • 用以连接数据库,这里我选用的是mysql
      package DAL;
      import com.mysql.jdbc.StatementImpl;
      import java.sql.*;
      
      public class SqlHelper {
          public static Connection getConnection() {
              Connection connection = null;
              try {
                  Class.forName("com.mysql.jdbc.Driver");
                  connection = DriverManager.getConnection("jdbc:mysql://127.0.0.1:3306/servletdata?useSSL=true&characterEncoding=utf-8&user=root&password=");
                  System.out.println("数据库连接成功!");
                  System.out.println("-------------------------------");
                  return connection;
              } catch (Exception e) {
                  e.printStackTrace();
              }
              System.out.println("创建连接失败!");
              System.out.println("-------------------------------");
              return null;
          }
          //select
          public static ResultSet executeQuery(String SQL)
          {
              try
              {
                  Connection conn=getConnection();
                  Statement stmt=conn.createStatement();
                  ResultSet rs=stmt.executeQuery(SQL);
                  return rs;
              } catch (SQLException e) {
                  e.printStackTrace();
                  System.out.println("查询失败!");
                  System.out.println("-------------------------------");
                  return null;
              }
          }
          //insert update delete
          public static boolean executeUpdate(String SQL)
          {
              try
              {
                  Connection conn=getConnection();
                  Statement stmt=conn.createStatement();
                  int rs=stmt.executeUpdate(SQL);
                  if (rs>0)
                      return true;
                  else
                      return false;
              } catch (SQLException e) {
                  e.printStackTrace();
                  System.out.println("更新失败!");
                  System.out.println("-------------------------------");
                  return false;
              }
          }
          public static void ShutDown(StatementImpl statement, Connection connection) {
              if (statement != null) {
                  try {
                      statement.close();
                  } catch (SQLException e) {
                      e.printStackTrace();
                  }
              }
              if (connection != null) {
                  try {
                      connection.close();
                  } catch (SQLException e) {
                      e.printStackTrace();
                  }
      
              }
          }
      }

2.3 Entity

  • News
    • 用于映射数据库中的news表
      package Entity;
      
      import java.sql.Date;
      
      public class News {
          private int idnews;
          private String category;
          private String title;
          private String content;
          private String author;
          private Date newsdate;
      
          public int getIdnews() {
              return idnews;
          }
          public void setIdnews(int idnews) {
              this.idnews = idnews;
          }
          public String getCategory() {
              return category;
          }
          public void setCategory(String category) {
              this.category = category;
          }
          public String getTitle() {
              return title;
          }
          public void setTitle(String title) {
              this.title = title;
          }
          public String getContent() {
              return content;
          }
          public void setContent(String content) {
              this.content = content;
          }
          public String getAuthor() {
              return author;
          }
          public void setAuthor(String author) {
              this.author = author;
          }
          public Date getNewsdate() {
              return newsdate;
          }
          public void setNewsdate(Date newsdate) {
              this.newsdate = newsdate;
          }
      
      }
  • Users
    • 用于映射数据库中的users表
      package Entity;
      
      public class Users {
          String name="";//用户名
          String password="";//用户密码
      
          public String getName() {
              return name;
          }
          public void setName(String name) {
              this.name = name;
          }
          public String getPassword() {
              return password;
          }
          public void setPassword(String password) {
              this.password = password;
          }
      }

2.4 Service

  • NewsService
    • 提供News类的数据服务(目前只完善了查询所有新闻内容的函数)
      package Service;
      
      import DAL.SqlHelper;
      import Entity.News;
      
      import java.sql.ResultSet;
      import java.sql.SQLException;
      import java.util.ArrayList;
      import java.util.List;
      
      public class NewsService {
          public void AddNews(){}
          public void DeleteNews(){}
          public void UpdateNews(){}
          public List<News> QueryNews() throws SQLException {
              String sql="Select * from news";
              ResultSet rs= SqlHelper.executeQuery(sql);
              List<News> lsNews=new ArrayList<News>();
              while (rs.next())
              {
                  News news=new News();
                  news.setIdnews(rs.getInt(1));
                  news.setCategory(rs.getString(2));
                  news.setTitle(rs.getString(3));
                  news.setContent(rs.getString(4));
                  news.setAuthor(rs.getString(5));
                  news.setNewsdate(rs.getDate(6));
                  lsNews.add(news);
              }
              return lsNews;
          }
          public void GetNews(){}
      }
  • UsersService
    • 提供Users类的数据服务(目前只完善了验证用户信息是否正确的函数)
      package Service;
      
      import DAL.SqlHelper;
      import Entity.News;
      import Entity.Users;
      import com.mysql.jdbc.PreparedStatement;
      
      import java.sql.ResultSet;
      import java.sql.SQLException;
      
      public class UsersService {
          public void AddUsers(){}
          public void DeleteUsers(){}
          public void UpdateUsers(){}
          public boolean QueryUsers(Users user) throws SQLException {
              //验证用户名存在性
              PreparedStatement pstmt;
              String sql = "select * from  users where username=\'"+user.getName()+"\' and password=\'"+user.getPassword()+"\'";
              ResultSet rs= SqlHelper.executeQuery(sql);
              if (rs.next()) {
                  return true;
              }
              return false;
          }
          public void GetUsers(){}
      }

2.5 Listener

2.6 Filter

2.7 Util

3、Web部分详细介绍

3.1 登录

登陆部分的网页无需修改,具体介绍见上一篇博客https://www.cnblogs.com/luomei/p/13034052.html

3.2 新闻后台管理

后台管理部分,我们需要先把模板内容调整为合适的内容,其中index.html是后台的主界面,其中菜单部分,我们需要把选项的href修改成ShowNewsListServlet,用以通过Servlet来实现网页信息的动态展示

 

在ShowNewsListjsp文件中,我们还需要增加循环的代码,其中的lsNews数据就是在ShowNewsListServlet通过服务获取到并传递给该jsp文件的数据

3.3 新闻展示(暂时还未使用)

 

 3.4 web.xml 配置文件

具体功能与上一博客介绍的无区别,可参考上一博客https://www.cnblogs.com/luomei/p/13034052.html进行配置。

4、效果展示

数据库数据:

用户数据

新闻数据

网页展示:

登录

 

 主页

 

 新闻管理页

5、码云地址

https://gitee.com/MavisLuo/JSPshowNews/tree/master

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