<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/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>

  <groupId>com.shyrolk</groupId>
  <artifactId>firstMybatis</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <packaging>jar</packaging>

  <name>firstMybatis</name>
  <url>http://maven.apache.org</url>

  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
  </properties>

  <dependencies>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>3.8.1</version>
      <scope>test</scope>
    </dependency>
    
    <dependency>
    <groupId>org.mybatis</groupId>
    <artifactId>mybatis</artifactId>
    <version>3.4.4</version>
</dependency>

<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>6.0.6</version>
</dependency>
  </dependencies>
</project>

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN" "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
    <environments default="development">
        <environment id="development">
            <transactionManager type="JDBC" />
            <!-- 配置数据库连接信息 -->
            <dataSource type="POOLED">
                <property name="driver" value="com.mysql.jdbc.Driver" />
                <property name="url" value="jdbc:mysql://localhost:3306/test?useUnicode=true&amp;useJDBCCompliantTimezoneShift=true&amp;useLegacyDatetimeCode=false&amp;serverTimezone=UTC" />
                <property name="username" value="root" />
                <property name="password" value="" />
            </dataSource>
        </environment>
    </environments>
    

    
</configuration>

package com.shyroke.entity;

public class User {
    private int id;
    private String userName;
    private String passWord;

    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 getPassWord() {
        return passWord;
    }

    public void setPassWord(String passWord) {
        this.passWord = passWord;
    }

    @Override
    public String toString() {
        return "User [id=" + id + ", userName=" + userName + ", passWord=" + passWord + "]";
    }

}

package com.shyroke.mapper;

import org.apache.ibatis.annotations.Param;

import com.shyroke.entity.User;

public interface UserMapper {
    public User findUserById(@Param("id")int id);
}

<?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.shyroke.mapper.UserMapper">
 
     
    <!-- 根据 id 查询 user 表中的数据
       id:唯一标识符，此文件中的id值不能重复
       resultType:返回值类型，一条数据库记录也就对应实体类的一个对象
       parameterType:参数类型，也就是查询条件的类型
    -->
    <select id="findUserById"
            resultType="com.shyroke.entity.User" parameterType="int">
        <!-- 这里和普通的sql 查询语句差不多，后面的 #{id}表示占位符，里面不一定要写id,写啥都可以，但是不要空着 -->
        select * from user where id = #{id}
    </select>
     
     
</mapper>

    <mappers>
        <mapper class="com.shyroke.mapper.UserMapper"/>
    </mappers>

package com.shyrolk.firstMybatis;

import java.awt.image.ImageProducer;
import java.io.InputStream;

import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;

import com.shyroke.entity.User;
import com.shyroke.mapper.UserMapper;


/**
 * Hello world!
 *
 */
public class App 
{
    public static void main( String[] args )
    {

        InputStream inputStream=App.class.getClassLoader().getResourceAsStream("resource/mybatis-config.xml");
        SqlSessionFactory sqlSessionFactory=new SqlSessionFactoryBuilder().build(inputStream);
        SqlSession sqlSession=sqlSessionFactory.openSession();
        
        UserMapper userMapper=sqlSession.getMapper(UserMapper.class);
        User user= userMapper.findUserById(1);
        System.out.println(user);
        sqlSession.close();
    }
}