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();
}