@SpringBootApplication
public class AysRestClientApplication {

private static final Logger log = LoggerFactory.getLogger(AysRestClientApplication.class);


    public static void main(String[] args) {
       ApplicationContext ctx = SpringApplication.run(AysRestClientApplication.class, args);
       RestClient cl = ctx.getBean(RestClient.class);
       cl.makeCall();
   }
}

@Service
public class GetChangesMClient {

private final RestTemplate restTemplate;
private final String url = "https://sample.org/restapi";

  public GetChangesMClient(RestTemplateBuilder restTemplateBuilder) {
    List<ClientHttpRequestInterceptor> interceptors = new ArrayList<ClientHttpRequestInterceptor>();
    interceptors.add(new HeaderRequestInterceptor("Accept", MediaType.APPLICATION_JSON_VALUE));

    this.restTemplate = restTemplateBuilder.basicAuthorization("username", "password").build();
    this.restTemplate.setInterceptors(interceptors);
}

public GetChangesMResponseTO execute(GetChangesMRequestTO request) {
    return this.restTemplate.postForObject(url, request, GetChangesMResponseTO.class);

}

}

class HeaderRequestInterceptor implements ClientHttpRequestInterceptor {

private final String headerName;
private final String headerValue;

public HeaderRequestInterceptor(String headerName, String headerValue) {
    this.headerName = headerName;
    this.headerValue = headerValue;
    System.out.println("Setting Interceptors");
}

@Override
public ClientHttpResponse intercept(HttpRequest request, byte[] body, ClientHttpRequestExecution execution) throws IOException {
    System.out.println("intercepted");
    request.getHeaders().set(headerName, headerValue);
    return execution.execute(request, body);
}

}

@Service
public class RestClient {

@Autowired
private GetChangesMClient client;

public void makeCall(){
    RequestTO request = new RequestTO();


    ResponseTO response = this.client.execute(request);

}
}