mybatis resultMap 中的association标签，没有设置javaType会空指针异常报错

org.apache.ibatis.exceptions.PersistenceException:

Error querying database. Cause: java.lang.NullPointerException

The error may exist in com/itheima/dao/IAccountDao.xml

The error may involve com.itheima.dao.IAccountDao.findAll

The error occurred while handling results

SQL: select u.* , a.id as aid,a.uid,a.money from account a,user u where u.id = a.uid;

Cause: java.lang.NullPointerException

解决方法 ：

设置javatype