[MyBatis]接口与配置文件动态绑定

目录结构

新建接口（不需要写实现）

package com.yiki.Dao;

import com.yiki.Entity.Person;

public interface PersonMapper {

public Person getPersonById(Integer id);
}

mybatis.xml

<?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"/>
            <dataSource type="POOLED">
                <property name="driver" value="com.mysql.jdbc.Driver"/>
                <property name="url" value="jdbc:mysql://localhost:3306/mybatis"/>
                <property name="username" value="root"/>
                <property name="password" value="9622738"/>
            </dataSource>
        </environment>
    </environments>

    <mappers>
        <mapper resource="PersonMapper.xml"/>
    </mappers>
</configuration>

PersonMapper.xml(重要！！！！）

<?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">

<!--名称空间：写指定接口的全类名
id:唯一标识,这里写接口里绑定的对应的接口方法
resultype:返回值类型(写全类名）
-->
<mapper namespace="com.yiki.Dao.PersonMapper">
    <select id="getPersonById" resultType="com.yiki.Entity.Person">
    <!-- select * from Person where pid = #{id}-->
    select  pid,p_name pname,email from Person where pid = #{id}
  </select>
</mapper>

测试类

package com.yiki.Test;

import com.yiki.Dao.PersonMapper;
import com.yiki.Entity.Person;
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 org.junit.Test;

import java.io.IOException;
import java.io.InputStream;

public class Tests{

 @Test
 public void select01() throws IOException {
  String resource = "mybatis.xml";//根据全局配置文件
  InputStream inputStream = Resources.getResourceAsStream(resource);
  SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);

  SqlSession sqlSession = sqlSessionFactory.openSession();
  PersonMapper mapper = sqlSession.getMapper(PersonMapper.class);
  Person person = mapper.getPersonById(1);
  System.out.println(person);

  sqlSession.close();

 }