JSP显示新闻

写在前面:

github链接:https://github.com/Eleanoren/-/tree/master/News

小组成员:吕登名、刘婧祺

界面随手写的没有仔细美化,见谅

class 位置:

JSP显示新闻

 1. 登录界面

JSP显示新闻

 

 附上代码:

 1 <%@ page contentType="text/html;charset=UTF-8" language="java" %>
 2 <html>
 3   <head>
 4     <title>登 录</title>
 5   </head>
 6   <body>
 7     <form method="post" name="frmlogin" action="Servlet/Servlet">
 8       <h1>用户登录</h1>
 9       <table border=1>
10         <tr>
11           <td>账号</td>
12           <td>
13             <input type="text" name="id" value="账号" size="20" maxlength="20"
14                    onfocus="if (this.value==‘账号‘)  this.value=‘‘;"/>
15           </td>
16         </tr>
17         <tr>
18           <td>密码</td>
19           <td>
20             <input type="password" name="password" value="密码" size="20" maxlength="20"
21                    onfocus="if (this.value==‘密码‘)  this.value=‘‘;"/>
22 
23           </td>
24 
25         </tr>
26         <tr>
27           <input type="submit" name="Submit" value="提交" onclick="return Login()"/>
28           <input type="reset" name="Reset" value="重置"/>
29         </tr>
30       </table>
31     </form>
32   <script>
33     function Login() {
34       var sUserName = document.frmlogin.id.value;
35       var sPassword = document.frmlogin.password.value;
36 
37       if ((sUserName == "") || (sUserName == "账号")) {
38         alert("请输入用户名!");
39         return false;
40       }
41       if ((sPassword == "") || (sPassword == "密码")) {
42         alert("请输入密码!");
43         return false;
44       }
45     }
46   </script>
47   </body>
48 </html>

2. 新闻显示界面

登录成功后,显示新闻内容:

 JSP显示新闻

 

 附上代码:

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>新闻</title>
</head>
<body>
<%
    String id = (String) session.getAttribute("id");
    String password = (String) session.getAttribute("password");
    String title1=(String) session.getAttribute("title1");
    String title2=(String) session.getAttribute("title2");
    String title3=(String) session.getAttribute("title3");
    String title4=(String) session.getAttribute("title4");

%>
<div align="center">
    <%=id %>
    欢迎您,登陆成功!<br/>
    <font color="blue">新闻</font>
    <table border=1>
        <tr>
            <td>&nbsp;账号:&nbsp;</td>
            <td>&nbsp;&nbsp;<%=id %>&nbsp;&nbsp;</td>
        </tr>
        <tr>
            <td>&nbsp;标题:&nbsp;</td>
            <td>&nbsp;&nbsp;<%=title1 %>&nbsp;&nbsp;</td>
        </tr>
        <tr>
            <td>&nbsp;标题:&nbsp;</td>
            <td>&nbsp;&nbsp;<%=title2 %>&nbsp;&nbsp;</td>
        </tr>
        <tr>
            <td>&nbsp;标题:&nbsp;</td>
            <td>&nbsp;&nbsp;<%=title3 %>&nbsp;</td>
        </tr>
        <tr>
            <td>&nbsp;标题:&nbsp;</td>
            <td>&nbsp;&nbsp;<%=title4 %>&nbsp;&nbsp;</td>
        </tr>
    </table>
    <a href="index.jsp">返回</a>
</div>
</body>
</html>

3. 用 Servlet 编写的的业务控制层实现对数据的操作

package Servlet;

import sql.JdbcCRUDByPreparedStatement;

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 javax.servlet.http.HttpSession;
import java.io.IOException;
import java.util.List;
import java.util.Map;

@WebServlet(name = "Servlet")
public class Servlet extends HttpServlet {
    private static final long serialVersionUID=1;
    public Servlet(){}
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException
    {
        response.setContentType("text/html;charset=UTF-8");
        request.setCharacterEncoding("UTF-8");

        String id=request.getParameter("id");
        String password=request.getParameter("password");
        String result;
        if ((id == "") || (id == null) || (id.length() > 20)) {
            try {
                result="请输入的用户名(不能超过20个字符)";
                request.setAttribute("massage",result);
                response.sendRedirect("/index.jsp");
            }catch (Exception e)
            {
                e.printStackTrace();
            }
        }
        if ((password == "") || (password == null) || (password.length() > 20)) {
            try {
                result = "请输入密码(不能超过20个字符)!";
                request.setAttribute("message", result);
                response.sendRedirect("/login.jsp");
            } catch (Exception e) {
                e.printStackTrace();
            }
        }

        String strsql = "select * from userInfo where id=‘" + id + "‘ and password= ‘" + password + "‘";
        JdbcCRUDByPreparedStatement ps = new JdbcCRUDByPreparedStatement();
        List<Map<String, Object>> list = ps.find(strsql);

        HttpSession session = request.getSession();
        session.setAttribute("username", id);
        String k1, m1;
        if (!list.isEmpty()) {
            for (Map<String, Object> m : list) {
                for (String k : m.keySet()) {
                    k1 = k;
                    m1 = String.valueOf(m.get(k));
                    session.setAttribute(k1, m1);
                }
            }
            response.sendRedirect("/NewsView.jsp");

        } else {
            session.setAttribute("message", "用户名或密码不匹配!");

        }
    }


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

    }
}

4. MySQL 新建数据库和数据表

create database news;
use news;
create table information(
    id varchar(20) not null primary key,
    password varchar(16) not null,
    title varchar(40) not null,
    source varchar(30) not null,
    content varchar(1000) not null,
    time varchar(20) not null
)ENGINE=InnoDB  DEFAULT CHARSET=utf8 AUTO_INCREMENT=1;
insert into information values(tom,123,标题1,标题2,标题3,标题4);

5. .JDBC连接类

JdbcUtils类:

package sql;
import java.sql.*;

public class JDBCunit {
    private static final String driver="com.mysql.jdbc.Driver";
    private static final String url="jdbc:mysql://localhost:3306";
    private static final String id="root";
    private static final String password="123456";

    static {
        try {
            Class.forName(driver);
        }catch (Exception e){
            throw new ExceptionInInitializerError(e);
        }
    }

    public static Connection getConnection() throws SQLException {
        return DriverManager.getConnection(url, id, password);
    }

    public static void release(Connection conn, Statement st, ResultSet rs) {
        if (rs != null) {
            try {
                rs.close();
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
        if (st != null) {
            try {
                st.close();
            } catch (Exception e) {
                e.printStackTrace();
            }
        }

        if (conn != null) {
            try {
                conn.close();
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }
}

JdbcCRUDByPreparedStatement类:

package sql;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class JdbcCRUDByPreparedStatement {
    private static Connection conn = null;
    private static PreparedStatement st = null;
    private static ResultSet rs = null;

    public List<Map<String, Object>> find(String strSql) {
        List<Map<String, Object>> list = new ArrayList();
        try {
            conn = JDBCunit.getConnection();
            st = conn.prepareStatement(strSql);
            rs = st.executeQuery();
            ResultSetMetaData rsmd = rs.getMetaData();
            while (rs.next()) {
                Map<String, Object> map = new HashMap();
                int columnCount = rsmd.getColumnCount();
                for (int i = 0; i < columnCount; i++) {
                    String columnName = rsmd.getColumnName(i + 1);
                    map.put(columnName, rs.getObject(i + 1));
                }
                list.add(map);
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            JDBCunit.release(conn, st, rs);
            return list;
        }
    }

}

6. web.xml配置

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
         version="4.0">
    <welcome-file-list>
        <welcome-file>index.jsp</welcome-file>
    </welcome-file-list>
    <servlet>
        <servlet-name>Servlet</servlet-name>
        <servlet-class>Servlet.Servlet</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>Servlet</servlet-name>
        <url-pattern>/Servlet</url-pattern>
    </servlet-mapping>
</web-app>

 

JSP显示新闻

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