MyBatis注解方式与映射文件方式配合实现一对一，一对多，多对多（三）

MyBatis注解方式与映射文件方式配合实现多对多

package com.dao;

import java.util.List;

import org.apache.ibatis.annotations.Insert;
import org.apache.ibatis.annotations.Many;
import org.apache.ibatis.annotations.Result;
i
4000
mport org.apache.ibatis.annotations.ResultMap;
import org.apache.ibatis.annotations.Results;
import org.apache.ibatis.annotations.Select;

import com.entity4.Group;
import com.entity4.User;

public interface GroupDao {

@Select("select * from groups")
@Results(
{
@Result(column="groupId",property="groupId",id=true),
@Result(column="groupName",property="groupName"),
@Result(column="groupId",property="userSet",many = @Many(select="getUser"))
}
)
public List<Group> getGroup();

@Select("select * from user2 where userId in (select userId from group_user where groupId = #{groupId} )")
@Results(
{
@Result(column="userId",property="userId",id=true),
@Result(column="userName",property="userName"),
}
)
public List<User> getUser();

}

/**
* 这种用法  配置文件 mapper.xml 一定要
* <mapper resource="com/dao/groupMapper.xml" />  >   <mapper namespace="com.dao.GroupDao">
* @return
*/
@Select("select * from groups")
@ResultMap("GroupMap")
public List<Group> getGroup2();

@Select("select * from user2 where userId in (select userId from group_user where groupId = #{groupId} )")
@ResultMap("User2Map")
public List<User> getUser2();

<?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.dao.GroupDao">

<resultMap type="Group" id="GroupMap">
<id column="groupId" property="groupId"/>
<result column="groupName" property="groupName"/>
<collection property="userSet" column="groupId" select="getUser2"></collection>
</resultMap>

<resultMap type="User2" id="User2Map">
<id column="userId" property="userId"/>
<result column="userName" property="userName"/>
</resultMap>

</mapper>