spring注解报错 Error creating bean

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'userService1': Injection of resource fields failed; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No unique bean of type [dao.UserDao] is defined: Unsatisfied dependency of type [interface dao.UserDao]: expected at least 1 matching bean

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