spring boot +mybatis 整合 association报空指针

Question

<resultMap id="userInfoMap" type="com.pwq.www.myProject.user.model.User">
        <id property="id" column="id" />
        <result property="username" column="username"/>
        <result property="password" column="password" />
        <association property="gender">
            <id property="id" column="id" />
            <result property="userId" column="user_id" />
            <result property="gender" column="gender" />
        </association>
    </resultMap>

    <select id="selectUserInfo" resultMap="userInfoMap">
        SELECT * FROM t_user u LEFT JOIN t_gender g ON (u.id = g.user_id) WHERE u.id = 1
    </select>
    

然后我调用了selectUserInfo方法报了空指针

实际是有值的

不知道哪里错了？

Answer 1

resultMap配置不正确，需要增加关联的gender的类型javaType="com.pwq.www.myProject.user.model.Gender"

<resultMap id="userInfoMap" type="com.pwq.www.myProject.user.model.User">
        <id property="id" column="id" />
        <result property="username" column="username"/>
        <result property="password" column="password" />
        <association property="gender" javaType="com.pwq.www.myProject.user.model.Gender">
            <id property="id" column="id" />
            <result property="userId" column="user_id" />
            <result property="gender" column="gender" />
        </association>
    </resultMap>

com.pwq.www.myProject.user.model.Gender 这个是猜的包名，需要再确认下是否是这个。