这是一个简单的用户登录功能
- 用户填写用户名密码，提交到LoginServlet
- 在LoginServlet中使用Mybatis查询数据库，验证用户名密码是否正确
- 如果正确，响应“登陆成功”，否则登陆失败
1.目录结构
2.target中的mapper和接口
3.报错信息
4.UserMapper接口代码
package com.oqs.mapper;
import com.oqs.pojo.User;
import org.apache.ibatis.annotations.Param;
import org.apache.ibatis.annotations.Select;
/**
* @author ikun
*/
public interface UserMapper {
@Select("select * from tb_user where username=#{username}} and paaword=#{password}")
User select(@Param("username") String username,@Param("password") String password);
}
5.UserMapper.xml
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.oqs.mapper.UserMapper">
</mapper>
6.LoginServlet代码
package com.oqs.web;
import com.oqs.mapper.UserMapper;
import com.oqs.pojo.User;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import javax.servlet.*;
import javax.servlet.http.*;
import javax.servlet.annotation.*;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.io.Writer;
/**
* @author ikun
*/
@WebServlet("/loginServlet")
public class LoginServlet extends HttpServlet {
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
String username = request.getParameter("username");
String password = request.getParameter("password");
String resource = "mybatis-config.xml";
InputStream inputStream = Resources.getResourceAsStream(resource);
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
SqlSession sqlSession = sqlSessionFactory.openSession();
UserMapper mapper = sqlSession.getMapper(UserMapper.class);
User user = mapper.select(username, password);
sqlSession.close();
response.setContentType("txt/html;charset=utf-8");
PrintWriter writer = response.getWriter();
if (user != null) {
//登陆成功
writer.write("登陆成功");
} else {
writer.write("登陆失败");
}
}
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doGet(request, response);
}
}
7.login.html代码
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>login</title>
<link href="css/login.css" rel="stylesheet">
</head>
<body>
<div id="loginDiv">
<form action="/request-demo2/loginServlet" method="post" id="form">
<h1 id="loginMsg">LOGIN IN</h1>
<p>Username:<input id="username" name="username" type="text"></p>
<p>Password:<input id="password" name="password" type="password"></p>
<div id="subDiv">
<input type="submit" class="button" value="login up">
<input type="reset" class="button" value="reset">
<a href="register.html">没有账号？点击注册</a>
</div>
</form>
</div>
</body>
</html>
8.mybatis配置文件
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
"https://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
<environments default="development">
<environment id="development">
<transactionManager type="JDBC"/>
<dataSource type="POOLED">
<property name="driver" value="com.mysql.jdbc.Driver"/>
<property name="url" value="jdbc:mysql:///db1?useSSL=false&useServerPrepStmts=true"/>
<property name="username" value="root"/>
<property name="password" value="root"/>
</dataSource>
</environment>
</environments>
<mappers>
<mapper resource="com.oqs.mapper.UserMapper.xml"/>
</mappers>
</configuration>
9.pom.xml
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>org.example</groupId>
<artifactId>request-demo2</artifactId>
<packaging>war</packaging>
<version>1.0-SNAPSHOT</version>
<name>request-demo2 Maven Webapp</name>
<url>http://maven.apache.org</url>
<properties>
<maven.compiler.source>8</maven.compiler.source>
<maven.compiler.target>8</maven.compiler.target>
</properties>
<dependencies>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>4.0.1</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.5.13</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.49</version>
</dependency>
<dependency>
<groupId>commons-io</groupId>
<artifactId>commons-io</artifactId>
<version>2.7</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>3.8.1</version>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<resources>
<resource>
<directory>src/main/resources</directory>
<includes>
<include>**/*.properties</include>
<include>**/*.xml</include>
</includes>
<filtering>true</filtering>
</resource>
<resource>
<directory>src/main/java</directory>
<includes >
<include>**/*.properties</include>
<include>**/*.xml</include>
</includes>
<filtering>true</filtering>
</resource>
</resources>
<plugins>
<plugin>
<groupId>org.apache.tomcat.maven</groupId>
<artifactId>tomcat7-maven-plugin</artifactId>
<version>2.2</version>
</plugin>
</plugins>
</build>
</project>
