Error creating bean with name 'serverImpl': Injection of autowired dependencies failed;

本来是好好的，后来报了这个错误，不知道怎么回事，然后看到下一句的报错，才了解到原来是在添加的时候多加了返回值类型，insert是没有返回值类型的，delete，update也是

Error creating bean with name ‘serverImpl’: Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: private com.tianyan.mapper.ServerMapper com.tianyan.service.ServerImpl.sm; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [com.tianyan.mapper.ServerMapper] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}

后来运行的时候，能添加成功，但是还报错误
insertServer’ has an unsupported return type: class com.tianyan.entity.Server

把接口中的方法改为void即可

	void insertServer(Server server);