一、web结构图
二、jsp（V）
<%-- Created by IntelliJ IDEA. User: Administrator Date: 2020/12/6 0006 Time: 18:41 To change this template use File | Settings | File Templates. --%> <%@ page contentType="text/html;charset=UTF-8" language="java" %> <html> <head> <title>$Title$</title> </head> <body> <center> <h1 style="color:red">登录</h1> <form id="indexform" name="indexForm" action="/web002/login" method="post"> <table border="0"> <tr> <td>账号：</td> <td><input type="text" name="username"></td> </tr> <tr> <td>密码：</td> <td><input type="password" name="password"> </td> </tr> </table> <br> <input type="submit" value="登录" style="color:#BC8F8F"> </form> </center> </body> </html>
三、servlet（C）
package com.login; 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.io.PrintWriter; import com.db.*; @WebServlet(name = "Servlet") public class Servlet extends HttpServlet { protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { request.setCharacterEncoding("UTF-8"); response.setCharacterEncoding("UTF-8"); response.setContentType("text/html;charset=UTF-8"); String username = request.getParameter("username"); String password = request.getParameter("password"); System.out.println(username); System.out.println(password); String html = null; Mysqldb db = new Mysqldb(); if (db.isLogin(username, password)) html = "<div style='color:green'>登入成功</div>"; else html = "<div style='color:red'>登入失败</div>"; PrintWriter pw = response.getWriter(); pw.println(html); db.close(); }
四、数据库（M）
package com.db; import java.sql.*; public class Mysqldb { // JDBC 驱动名及数据库 URL static final String JDBC_DRIVER = "com.mysql.jdbc.Driver"; static final String DB_URL = "jdbc:mysql://10.0.0.101:3306/admin?useSSL=false"; // 数据库的用户名与密码，需要根据自己的设置 static final String USER = "root"; static final String PASS = "root"; private Connection conn = null; private PreparedStatement stmt = null; private ResultSet resultset = null; public Mysqldb() { try { Class.forName(JDBC_DRIVER); conn = DriverManager.getConnection(DB_URL, USER, PASS); System.out.println("数据连接成功！"); } catch (Exception ex) { ex.printStackTrace(); System.out.println("数据连接失败！"); } } public boolean isLogin(String username, String password) { try { String sql = "select * from login where username=?"; stmt = conn.prepareStatement(sql); stmt.setString(1, username); resultset = stmt.executeQuery(); if (resultset != null) { while (resultset.next()) { String pwd = resultset.getString("password"); System.out.println("pwd:"+pwd); if (pwd.equals(password)) { return true; } else { return false; } } } else { return false; } } catch (Exception ex) { System.out.println("ִ执行查询错误！"); } return false; } public void close() { try { stmt.close(); conn.close(); } catch (Exception e) { } } }
五、xml配置文件
<?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>LoginServlet</servlet-name> <servlet-class>com.login.Servlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>LoginServlet</servlet-name> <url-pattern>/login</url-pattern> </servlet-mapping> </web-app>