Could not autowire. No beans of 'xxxx' type found

初学 Springboot ， 自动注入Service层的类时   idea编译器报错

网上查了一下， 对项目编译无影响    然而我的编译报错

2018-09-30 10:18:04.570 ERROR 3924 --- [           main] o.s.b.d.LoggingFailureAnalysisReporter   : 

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APPLICATION FAILED TO START
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Description:

Field girlService in com.sb.GirlController required a bean of type 'com.sb.GirlService' that could not be found.

Action:

Consider defining a bean of type 'com.sb.GirlService' in your configuration.
 

 原来   我没有在service层的类前面写注解  @Service

新手犯的错误，  就像controller层要写@RentController 一样