学步园

ClassesMapper.xml

<?xml version="1.0" encoding="UTF-8"?><br /> <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd"><br /> <mapper namespace="com.nantian.mybatis.one2one.ClassesMapper"><br /> <resultMap type="Classes" id="classes"><br /> <id property="id" column="c_id" javaType="int" jdbcType="INTEGER"/><br /> <result property="name" column="c_name" javaType="string" jdbcType="VARCHAR"/><br /> <association property="teacher" column="c_t_id" javaType="Teacher"><br /> <id property="id" column="t_id" javaType="int" jdbcType="INTEGER"/><br /> <result property="name" column="t_name" javaType="string" jdbcType="VARCHAR"/><br /> </association><br /> </resultMap></p> <p> <select id="one2one" parameterType="int" resultMap="classes"><br /> select c.c_id,c.c_name,c.c_t_id,t.t_id,t.t_name<br /> from classes c join teacher t on c.c_t_id = t.t_id where c.c_id = #{id}<br /> </select><br /> </mapper>

Classes

package com.nantian.mybatis.one2one;</p> <p>public class Classes {<br /> private int id;<br /> private String name;<br /> private Teacher teacher;</p> <p> public int getId() {<br /> return id;<br /> }</p> <p> public void setId(int id) {<br /> this.id = id;<br /> }</p> <p> public String getName() {<br /> return name;<br /> }</p> <p> public void setName(String name) {<br /> this.name = name;<br /> }</p> <p> public Teacher getTeacher() {<br /> return teacher;<br /> }</p> <p> public void setTeacher(Teacher teacher) {<br /> this.teacher = teacher;<br /> }<br /> }

ClassesMapper

package com.nantian.mybatis.one2one;</p> <p>public interface ClassesMapper {<br /> public Classes one2one(int id);<br /> }

Teacher

 package com.nantian.mybatis.one2one;</p> <p>public class Teacher {<br /> private int id;<br /> private String name;</p> <p> public int getId() {<br /> return id;<br /> }</p> <p> public void setId(int id) {<br /> this.id = id;<br /> }</p> <p> public String getName() {<br /> return name;<br /> }</p> <p> public void setName(String name) {<br /> this.name = name;<br /> }<br /> }  

T

package com.nantian.mybatis.one2one;</p> <p>import org.apache.ibatis.session.SqlSession;</p> <p>import com.nantian.mybatis.data.DBUtil;</p> <p>public class T {</p> <p> public static void main(String[] args) {<br /> SqlSession sqlSession = DBUtil.getInstance().getSqlSessionFactory()<br /> .openSession();<br /> try {<br /> ClassesMapper classesMapper = sqlSession<br /> .getMapper(ClassesMapper.class);<br /> Classes classes = classesMapper.one2one(1);<br /> Teacher teacher = classes.getTeacher();<br /> System.out.println(classes.getId());<br /> System.out.println(classes.getName());<br /> System.out.println(teacher.getId());<br /> System.out.println(teacher.getName());<br /> } finally {<br /> sqlSession.close();<br /> }<br /> }</p> <p>}