If you're using Spring Boot 1.4.0 or later as the basis of your annotation-driven, Spring doesn't provides a single auto-configured RestTemplate bean. From their documentation:
https://docs.spring.io/spring-boot/docs/1.4.0.RELEASE/reference/html/boot-features-restclient.html
If you need to call remote REST services from your application, you can use Spring Frameworkâs RestTemplate class. Since RestTemplate instances often need to be customized before being used, Spring Boot does not provide any single auto-configured RestTemplate bean. It does, however, auto-configure a RestTemplateBuilder which can be used to create RestTemplate instances when needed. The auto-configured RestTemplateBuilder will ensure that sensible HttpMessageConverters are applied to RestTemplate instances.