在MyBatis中一对一映射assocation嵌套查询问题

[带翅膀的猫]

这是mapper.xml映射文件：
<!-- assocation的嵌套查询 -->
<resultMap type="orders" id="ordersUserMap5" extends="ordersMap">
<association property="user" column="{id=userId}" select="selectUserById"/>
</resultMap>

<resultMap type="orders" id="ordersMap">
<id property="id" column="oid"/>
<result property="userId" column="userId"/>
<result property="number" column="number"/>
<result property="createtime" column="createtime"/>
<result property="note" column="note"/>
</resultMap>

<resultMap type="user" id="userMap">
<result property="id" column="id" />
<result property="username" column="username"/>
<result property="address" column="address"/>
<result property="sex" column="sex"/>
</resultMap>

<select id="selectUserById" parameterType="int" resultMap="userMap">
select id,username,sex,adderss from user where id=#{id}
</select>

<select id="queryOrdersUserById" parameterType="int" resultMap="ordersUserMap5">
select id,userId,number,createtime,note from orders where id=#{id}
</select>

这是测试类：
public void TestSelectOrdersAndUserById() {
SqlSession session = sqlSessionFactory.openSession();
OrdersMapper mapper = session.getMapper(OrdersMapper.class);
Orders orders = mapper.queryOrdersUserById(3);
System.out.println(orders);

session.commit();session.close();
}

出现错误：
Setting autocommit to false on JDBC Connection [com.mysql.jdbc.Connection@3cfcde5a]
==> Preparing: select id,userId,number,createtime,note from orders where id=?
==> Parameters: 3(Integer)在这就出错了：
Cause: java.lang.NoSuchMethodException: java.lang.Integer.<init>()

[Timor_D]

看下你的数据库连接是不是出现问题了

[带翅膀的猫]

现在搞定了，是由于assocation的column中不应该是id=userId,而是userId

[hp961218]

<resultMap type="orders" id="ordersUserMap5" extends="ordersMap">
<association property="user" column="{id=userId}" select="selectUserById"/>
</resultMap>

没搞懂配这个是要干嘛