code: public RESTResponse call(RESTClient restClient){        
          
          String methodName = getMethod();
          String uri = getURI();
          StringBuilder uriBuilder = new StringBuilder(Utils.isEmpty(restClient.getApiPrefix()) ? "" : "/" + restClient.getApiPrefix());
          uriBuilder.append(substitute(uri));     
          uri = uriBuilder.toString();
          try {           
              byte[] body = getBody(methodName);                                  
              RESTResponse response = sendRequest(restClient, methodName, uri, body);
              return response;            
          } catch (Exception e) {
               throw new RuntimeException(e);
          }            
      }
docs: Call method implementation
  @param restClient
  @return RESTResponse result object