Mapped Statements collection does not contain value for

问题：

Caused by: org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.exceptions.PersistenceException: 
### Error querying database.  Cause: java.lang.IllegalArgumentException: Mapped Statements collection does not contain value for com.xxx.xxx.customer.component.dao.IPolicyCustomerDAO.select
### Cause: java.lang.IllegalArgumentException: Mapped Statements collection does not contain value for com.xxx.xxx.customer.component.dao.IPolicyCustomerDAO.select
	at org.mybatis.spring.MyBatisExceptionTranslator.translateExceptionIfPossible(MyBatisExceptionTranslator.java:77)
	at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:446)
	at com.sun.proxy.$Proxy153.selectOne(Unknown Source)
	at org.mybatis.spring.SqlSessionTemplate.selectOne(SqlSessionTemplate.java:166)
	at com.zatech.octopus.module.mybatis.base.dao.AbstractBaseDaoImpl.queryOf(AbstractBaseDaoImpl.java:55)
	... 39 more
Caused by: org.apache.ibatis.exceptions.PersistenceException: 
### Error querying database.  Cause: java.lang.IllegalArgumentException: Mapped Statements collection does not contain value for com.xxx.xxx.customer.component.dao.IPolicyCustomerDAO.select
### Cause: java.lang.IllegalArgumentException: Mapped Statements collection does not contain value for com.xxx.xxx.customer.component.dao.IPolicyCustomerDAO.select
	at org.apache.ibatis.exceptions.ExceptionFactory.wrapException(ExceptionFactory.java:30)
	at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:149)
	at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:140)
	at org.apache.ibatis.session.defaults.DefaultSqlSession.selectOne(DefaultSqlSession.java:76)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:433)
	... 42 more			

解决方案：由于mapper.xml文件的namespace不对造成该映射找不到，所以报错