JSP显示新闻

JSP显示新闻

1、项目结构

　　java：

　　Web：

 

 

2、Java部分详细介绍

2.1 Controller

• GetSessionServlet：　
  • 显示在线人数的Servlet，具体介绍见上一篇博客https://www.cnblogs.com/luomei/p/13034052.html
• 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 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 QueryNews() throws SQLException {
            String sql="Select * from news";
            ResultSet rs= SqlHelper.executeQuery(sql);
            List lsNews=new ArrayList();
            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

• OnlineCounterListener：
  
  • 监听Session的创建与销毁，具体介绍见上一篇博客https://www.cnblogs.com/luomei/p/13034052.html

2.6 Filter

• GBFilter：　
  • 过滤器，处理乱码问题，具体介绍见上一篇博客https://www.cnblogs.com/luomei/p/13034052.html

2.7 Util

• CookieSave：　
  • 保存Cookie的工具类，具体介绍见上一篇博客https://www.cnblogs.com/luomei/p/13034052.html

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