Spring 注入问题

问题描述：

build成功，clean install也成功，tomcat启动时报错，

No qualifying bean of type [××××××××××Dao] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency.

折腾了半天，查了很多资料，context配置没问题，注解都没问题，最后才发现是Dao的impl没实现，简直要崩溃成灾。。