### Error querying database. Cause: java.lang.IllegalArgumentException: Mapped Statements collection does not contain value for student.selectAll

org.apache.ibatis.exceptions.PersistenceException:
### Error querying database. Cause: java.lang.IllegalArgumentException: Mapped Statements collection does not contain value for student.selectAll
### Cause: java.lang.IllegalArgumentException: Mapped Statements collection does not contain value for student.selectAll

 

原因：没有在MyBatis的xml配置文件中声明映射器

 

解决：在MyBatis的xml配置文件中加入

 <mappers>

　　<mapper resource="mappers/goods.xml"></mapper>

</mappers>

mappers只有一个，mapper可以多个