logger.warn("Failed to process a request.", e);
                throwValidationErrorApi(messages -> messages.addErrorsCrudFailedToCreateCrudTable(GLOBAL, buildThrowableMessage(e)));
            }
            return entity;
        }).orElseGet(() -> {
            throwValidationErrorApi(messages -> messages.addErrorsCrudFailedToCreateInstance(GLOBAL));
            return null;
        });

 *    either peer may not have been transmitted to the other.
 *
 * Note that the state progression is independent for each peer. Arriving at a gracefully-closed
 * state indicates that a peer has sent all of its outgoing messages and received all of its
 * incoming messages. But it does not guarantee that the other peer will successfully receive all of
 * its incoming messages.
 */
interface WebSocket {

                logger.warn("Failed to process a request.", e);
                throwValidationError(messages -> messages.addErrorsFailedToUploadMappingFile(GLOBAL),
                        () -> redirectWith(getClass(), moreUrl("uploadpage/" + form.dictId)));
            }
            saveInfo(messages -> messages.addSuccessUploadMappingFile(GLOBAL));

            try {
                failureUrlService.delete(entity);
                saveInfo(messages -> messages.addSuccessCrudDeleteCrudTable(GLOBAL));
            } catch (final Exception e) {
                logger.warn("Failed to process a request.", e);
                throwValidationErrorApi(messages -> messages.addErrorsCrudFailedToDeleteCrudTable(GLOBAL, buildThrowableMessage(e)));
            }
        }).orElse(() -> {

            try {
                crawlingInfoService.delete(entity);
                saveInfo(messages -> messages.addSuccessCrudDeleteCrudTable(GLOBAL));
            } catch (final Exception e) {
                logger.warn("Failed to process a request.", e);
                throwValidationErrorApi(messages -> messages.addErrorsCrudFailedToDeleteCrudTable(GLOBAL, buildThrowableMessage(e)));
            }
        }).orElse(() -> {

            if (logger.isDebugEnabled()) {
                logger.debug("Invalid offset: {}", form.offset, e);
            }
            throwValidationError(messages -> messages.addErrorsResultSizeExceeded(GLOBAL), this::asListHtml);
        }

        throwValidationError(messages -> messages.addErrorsInvalidQueryUnknown(GLOBAL), this::asListHtml);
        return null; // ignore
    }

    /**

                logger.warn("Failed to print a thread dump.", e);
                throwValidationError(messages -> messages.addErrorsFailedToPrintThreadDump(GLOBAL), this::asListHtml);
            }
        }).orElse(() -> {
            throwValidationError(messages -> messages.addErrorsCrudCouldNotFindCrudTable(GLOBAL, id), this::asListHtml);
        });
        return redirect(getClass());
    }

                logger.warn("Failed to add {}", entity, e);
                throwValidationError(messages -> messages.addErrorsCrudFailedToCreateCrudTable(GLOBAL, buildThrowableMessage(e)),
                        this::asEditHtml);
            }
        }).orElse(() -> {
            throwValidationError(messages -> messages.addErrorsCrudFailedToCreateInstance(GLOBAL), this::asEditHtml);
        });
        return redirect(getClass());

        body.dictId = dictId;
        validateApi(body, messages -> {});
        body.crudMode = CrudMode.CREATE;
        final StopwordsItem entity = createStopwordsItem(body, () -> {
            throwValidationErrorApi(messages -> messages.addErrorsCrudFailedToCreateInstance(GLOBAL));
            return null;
        }).orElseGet(() -> {
            throwValidationErrorApi(messages -> messages.addErrorsCrudFailedToCreateInstance(GLOBAL));

                logger.warn("Failed to process a request.", e);
                throwValidationErrorApi(messages -> messages.addErrorsCrudFailedToUpdateCrudTable(GLOBAL, buildThrowableMessage(e)));
            }
            return entity;
        }).orElseGet(() -> {
            throwValidationErrorApi(messages -> messages.addErrorsCrudCouldNotFindCrudTable(GLOBAL, body.id));
            return null;
        });