If the goal is to have a reusable RestTemplate which is in general useful for attaching the same header to a series of similar request a org.springframework.boot.web.client.RestTemplateCustomizer
parameter can be used with a RestTemplateBuilder
:
String accessToken= "<the oauth 2 token>";
RestTemplate restTemplate = new RestTemplateBuilder(rt-> rt.getInterceptors().add((request, body, execution) -> {
request.getHeaders().add("Authorization", "Bearer "+accessToken);
return execution.execute(request, body);
})).build();