code: public MwsCall newCall(String servicePath, String operationName) {
          if (!frozen) {
              freeze();
          }
          ServiceEndpoint sep = getServiceEndpoint(servicePath);
          // in future use sep+config to determine MwsCall implementation.
          return new MwsAQCall(this, sep, operationName);
      }
docs: Create a new request.
  <p>
  After first call to this method connection parameters can no longer be
  updated.
  
  @param servicePath
  @param operationName
  
  @return A new request.