第四次作业

JSP显示新闻 第四次作业

 

小组成员：郭昭杰    唐任峻杰

码云地址：https://gitee.com/ashes-g/JSP

一、数据库相关准备

新闻相关信息数据

 登录相关信息数据

二、新闻类

新建新闻类News，用于获取和设置新闻的各项属性

package Service;

import java.util.Date;

public class News {
    public News(){}
    private int newsID;
    private String newsCategory;
    private String newsTitle;
    private String newsContent;
    private String newsAuthor;
    private Date newsDate;

    public int getNewsID(){
        return newsID;
    }

    public void setNewsID(int newsID){
        this.newsID=newsID;
    }

    public String getNewsCategory(){
        return newsCategory;
    }

    public void setNewsCategory(String newsCategory){

        this.newsCategory= this.newsCategory;
    }

    public String getNewsTitle(){
        return newsTitle;
    }

    public void setNewsTitle(String newsTitle){

        this.newsTitle= this.newsTitle;
    }

    public String getNewsContent(){

        return newsContent;
    }

    public void setNewsContent(String newsContent){

        this.newsContent= this.newsContent;
    }

    public String getNewsAuthor(){

        return newsAuthor;
    }

    public void setNewsAuthor(String newsAuthor){

        this.newsAuthor= this.newsAuthor;
    }

    public Date getNewsDate(){

        return newsDate;
    }

    public void setNewsDate(java.sql.Date newsDate){
        this.newsDate= this.newsDate;
    }
}

三、新闻服务类

新建新闻服务类NewsService，向数据库中查询所有新闻信息，并将每条新闻生成一个新闻对象装入List中并返回

package Controller;

import Service.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 ShowNewsServlet 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 | ClassNotFoundException e) {
            e.printStackTrace();
        }
    }
}

四、登录

根据用户输入的用户名和密码查询登录信息数据库，若验证正确则进入index.jsp页面显示欢迎信息，若验证失败则提示用户名或密码错误

package Controller;

import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.*;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;


@WebServlet(name = "Controller.LoginServlet")
public class LoginServlet extends HttpServlet {
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
                response.setContentType("text/html; charset=UTF-8");
                request.setCharacterEncoding("UTF-8");

        PrintWriter output=response.getWriter();
        String username = request.getParameter("username");
        String pwd = request.getParameter("pwd");
        //output.println("账号:  "+username+"  密码:  "+pwd+"<br>");
        ResultSet rs ;
        Statement statement = null;
        Connection conn =null;

        try {
            Class.forName("com.mysql.jdbc.Driver");
            conn = DriverManager.getConnection("jdbc:mysql://localhost:3306","root","Guozhaojie610");
            String sql="select * from new_schema.login where username='"+username+"' and password='"+pwd+"'";
            statement =conn.createStatement();
            rs = statement.executeQuery(sql);



            if(rs.next()){
                request.setAttribute("username",username);
                request.getRequestDispatcher("index.jsp").forward(request,response);

            }else {
                output.println("账号或密码错误");
            }


        } catch (Exception e) {
            e.printStackTrace();
        }
    }

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

五、新闻显示

进入欢迎页面5秒后自动跳转至新闻显示页面

欢迎页面：

<%--
  Created by IntelliJ IDEA.
  User: Administrator
  Date: 2020/6/2
  Time: 16:36
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<% response.setHeader("refresh", "5;ShowNewsList");%>
<html>
<head>
  <title>$Title$</title>
</head>
<body>
<h3>登陆成功！</h3>
<h4>当前用户：${username}</h4>
<h4>5秒后自动跳转至新闻页面...</h4>
</body>
</html>

新闻显示页面调用控制层代码获取新闻信息并显示

控制层代码：

package Controller;

import Service.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 ShowNewsServlet 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 | ClassNotFoundException e) {
            e.printStackTrace();
        }
    }
}

六、最终效果截图

登录界面：

 登录成功：

 新闻页面：