code: @Override
      public DocumentTranslationRequestData updateDocumentTranslationRequest(
              String trId, DocumentTranslationRequestDataChangeSet changeSet)
              throws ServiceException {
          if (trId == null || trId.isEmpty()) {
              throw new IllegalArgumentException("Non-empty trId must be specified.");
          }
          if (changeSet == null) {
              throw new IllegalArgumentException("Non-null changeSet must be specified.");
          }
  
          RestInputDocumentTranslationRequestData restChangeSet = new RestInputDocumentTranslationRequestData(changeSet);
          Gson gson = createGson(RestInputDocumentTranslationRequestData.class.getName());
          String jsonBody = gson.toJson(restChangeSet, RestInputDocumentTranslationRequestData.class);
          DocumentTranslationRequestResponse resp = invokeApiJson(
                  "POST",
                  escapePathSegment(account.getInstanceId()) + "/v2/doc-trs/"
                          + escapePathSegment(trId),
                  jsonBody,
                  DocumentTranslationRequestResponse.class);
  
          if (resp.getStatus() == Status.ERROR) {
              throw new ServiceException(resp.getMessage());
          }
  
          return new DocumentTranslationRequestDataImpl(resp.id, resp.translationRequest);
      }
docs: /* (non-Javadoc)
  @see com.ibm.g11n.pipeline.client.ServiceClient#updateDocumentTranslationRequest(java.lang.String, com.ibm.g11n.pipeline.client.DocumentTranslationRequestDataChangeSet)