SvcABean.java

@Autowired
TokenString tokenString;
public CompletableFuture<String> callBAsync() { 
 return supplyAsync(() -> { 
    logger.info("calling B");
    RestTemplate restTemplate = new RestTemplate();
    HttpHeaders headers = new HttpHeaders();
    headers.set("Authorization", "bearer "+tokenString.getValue());
    HttpEntity entity = new HttpEntity(headers);
    ResponseEntity re = restTemplate.exchange(
          <SERVICE_B_ADDRESS>, 
          HttpMethod.GET, 
          entity, 
          String.class);
    return re.getStatusCode().equals(HttpStatus.OK) ? 
          "ok" : "not ok";
 });
}