mybatis種的ResultMap嵌套

mybatis中的返回類嵌套一個list，如何實現？

    <resultMap id="CusMap" type="com.yang.webstarter.entity.SysUser">
        <collection property="books" javaType="java.util.ArrayList" ofType="com.yang.webstarter.entity.UserBook"
                    select="selectUserBook"
                    column="{userId=id}"/>
    </resultMap>

    <select id="selectCusList" resultMap="CusMap">
        select *
        from sys_user
    </select>

    <select id="selectUserBook" resultType="com.yang.webstarter.entity.UserBook">
        select *
        from user_book
        where user_id = #{userId}
    </select>

調用返回

參考：https://www.cnblogs.com/mark5/p/15559640.html