JavaEE第一次实验复习servlet,JDBC

实验1


1.运行截图

JavaEE第一次实验复习servlet,JDBC

JavaEE第一次实验复习servlet,JDBC

2.代码

  1. 结构图

JavaEE第一次实验复习servlet,JDBC

2.bean

package com.ding.bean;

/**
 * @Description TODO
 * @Author 丁帅帅
 * @Date 21/09/11 18:56
 * @Version 1.0
 */
public class Add {

    private int a;
    private int b;

    public Add() {
    }

    public Add(int a, int b) {
        this.a = a;
        this.b = b;
    }

    public int getA() {
        return a;
    }

    public void setA(int a) {
        this.a = a;
    }

    public int getB() {
        return b;
    }

    public void setB(int b) {
        this.b = b;
    }

    public int sum(){
        int c,s=0;
        if(a>b){
            c=a;
            a=b;
            b=c;
        }
        for(int x=a;x<=b;++x){
            s+=x;

        }
        return s;
    }

    @Override
    public String toString() {
        return
                "a=" + a +
                ", b=" + b +",a+...+b="+sum();
    }
}

3.controller

package com.ding.controller;

import com.ding.bean.Add;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * @Description TODO
 * @Author 丁帅帅
 * @Date 21/09/11 18:33
 * @Version 1.0
 */
public class Chuli extends HttpServlet {

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        req.setCharacterEncoding("UTF-8");
        resp.setCharacterEncoding("UTF-8");
        String s1=req.getParameter("shuju1");
        String s2=req.getParameter("shuju2");

        int d1=Integer.parseInt(s1);
        int d2=Integer.parseInt(s2);

        Add two =new Add(d1,d2);
        String sum=two.toString();

        req.setAttribute("sum",sum);
        req.getRequestDispatcher("show.jsp").forward(req,resp);


    }


    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        super.doPost(req, resp);
    }
}

4.web.xml

<?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">


    <servlet>
        <servlet-name>default</servlet-name>
        <servlet-class>com.ding.controller.Chuli</servlet-class>
    </servlet>

    <servlet-mapping>
        <servlet-name>default</servlet-name>
        <url-pattern>/chuli</url-pattern>
    </servlet-mapping>

<welcome-file-list>
    <welcome-file>input.jsp</welcome-file>
</welcome-file-list>
</web-app>

5.input.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Title</title>
</head>
<body>
  <form action="chuli" method="post">
      数据1:<input name="shuju1"/><br>
      数据2:<input name="shuju2"/><br>
      <input type="submit" value="提交"/>
  </form>
</body>
</html>

6.show.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>展示页面</title>
</head>
<body>
<%
    Object sum = request.getAttribute("sum");

    out.print(sum);
%>
</body>
</html>

实验2


1.运行截图

JavaEE第一次实验复习servlet,JDBC

JavaEE第一次实验复习servlet,JDBC

2.代码

1.结构图

JavaEE第一次实验复习servlet,JDBC

2.bean

package com.ding.bean;

/**
 * @Description TODO
 * @Author 丁帅帅
 * @Date 21/09/11 19:52
 * @Version 1.0
 */
public class Student {

    private int id;
    private String username;
    private String userpassword;

    public Student(int id, String username, String userpassword) {
        this.id = id;
        this.username = username;
        this.userpassword = userpassword;
    }

    public Student() {
    }

    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 getUserpassword() {
        return userpassword;
    }

    public void setUserpassword(String userpassword) {
        this.userpassword = userpassword;
    }
}

3.controller

package com.ding.controller;


import com.ding.dao.UserDao;

import java.io.IOException;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;



@WebServlet("/loginCheck")
public class LoginCheck extends HttpServlet{
    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        doGet(req, resp);
    }
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        String uname=req.getParameter("uname");
        String pwd=req.getParameter("pwd") ;
        UserDao ud =new UserDao();
        boolean flag=ud.login(uname,pwd);
        if(flag) {
            req.setAttribute("name", uname);
            req.getRequestDispatcher("welcome.jsp").forward(req, resp);
        }
        else {

            req.getRequestDispatcher("login.jsp").forward(req, resp);
        }

    }
}

4.dao

package com.ding.dao;

import com.ding.utis.JDBCUtils;
import sun.security.util.Password;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

/**
 * @Description TODO
 * @Author 丁帅帅
 * @Date 21/09/11 20:13
 * @Version 1.0
 */
public class UserDao {


    private Connection conn=null;
    private PreparedStatement pstmt=null;
    private ResultSet rs=null;

    public boolean login(String name, String password) {
        try {
            conn=JDBCUtils.getConnection();
            String sql="select *from student where name=? and password=?";
            pstmt=conn.prepareStatement(sql);

            pstmt.setString(1,name);
            pstmt.setString(2,password);
            rs=pstmt.executeQuery();
            /*
             * if(rs.next()) { return true; }else { return false; }
             */
            return rs.next();
        } catch (SQLException e) {

            e.printStackTrace();
        }finally {
            JDBCUtils.close(rs, pstmt, conn);
        }
        return false;
    }
}

5.utis

package com.ding.utis;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.net.URL;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;


/**
 * @Description TODO
 * @Author 丁帅帅
 * @Date 21/09/11 20:08
 * @Version 1.0
 */

public class JDBCUtils {
    private static String url;
    private static String user;
    private static String password;
    private static String driver;

    static {
        try {
            Properties pro =new Properties();
            ClassLoader classLoader=JDBCUtils.class.getClassLoader();
            URL res=classLoader.getResource("jdbc.properties");
            String path=res.getPath();

            pro.load(new FileReader(path));
            url=pro.getProperty("url");
            user=pro.getProperty("user");
            password=pro.getProperty("password");
            driver=pro.getProperty("driver");

            Class.forName(driver);
        } catch (FileNotFoundException e) {

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

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

            e.printStackTrace();
        }
    }

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


    public static void close(Statement stmt,Connection conn) {
        if(stmt!=null) {
            try {
                stmt.close();
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            if(conn!=null) {
                try {
                    conn.close();
                } catch (SQLException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }


        }
    }

    public static void close(ResultSet rs, Statement pstmt, Connection conn) {
        if(rs!=null) {
            try {
                rs.close();
            } catch (SQLException e) {

                e.printStackTrace();
            }
        }

        if(pstmt!=null) {
            try {
                pstmt.close();
            } catch (SQLException e) {

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

                    e.printStackTrace();
                }
            }

        }
    }

}

6.login

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Title</title>
</head>
<body>
<form action="loginCheck" method="post">
    姓名:<input type="text" name="uname"><br>
    密码:<input type="password" name="pwd"><br>
    <input type="submit" value="登录"><br>
</form>
</body>
</html>

7.welcome

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Title</title>
</head>
<body>
<h1>欢迎${requestScope.name}登录成功!!!</h1>
</body>
</html>
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