}

    protected void processSystemError(final Object... objs) {
        final Throwable t = (Throwable) objs[0];
        if (logger.isErrorEnabled()) {
            logger.error("System Error.", t);
        }
    }

    protected void processNoRule(final Object... objs) {
        // CrawlerContext crawlerContext = (CrawlerContext) objs[0];
        // UrlQueue<?> urlQueue = (UrlQueue<?>) objs[1];

        }
        for (final String name : loggerNames) {
            if (loggerName.startsWith(name)) {
                final Level sourceLevel = event.getLevel();
                if (sourceLevel != Level.ERROR) {
                    return event;
                }
                return new Log4jLogEvent.Builder(event).setLevel(Level.WARN).build();
            }
        }
        return event;
    }

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.codelibs.fess.Constants;
import org.codelibs.fess.app.web.base.FessSearchAction;
import org.codelibs.fess.app.web.error.ErrorAction;
import org.codelibs.fess.util.DocumentUtil;
import org.lastaflute.web.Execute;
import org.lastaflute.web.response.ActionResponse;
import org.lastaflute.web.response.StreamResponse;

                CopyUtil.copy(in, out);
            } catch (final ClientAbortException e) {
                logger.debug("Client aborts this request.", e);
            } catch (final IOException e) {
                logger.error("Failed to read {} from {}", path, filePath);
                throw new WebApiException(HttpServletResponse.SC_INTERNAL_SERVER_ERROR, e);
            }
        } else {
            try {

            if (logger.isDebugEnabled()) {
                logger.error("IndexUpdater is terminated.", e);
            } else if (logger.isInfoEnabled()) {
                logger.info("IndexUpdater is terminated.");
            }
            forceStop();
        } catch (final Throwable t) {
            if (ComponentUtil.available()) {
                logger.error("IndexUpdater is terminated.", t);

                try {
                    CloseableUtil.closeQuietly(p.getErrorStream());
                } catch (final Exception e) {
                    logger.warn("Could not close a process error stream.", e);
                }
            });
            CommonPoolUtil.execute(() -> {
                try {
                    CloseableUtil.closeQuietly(p.getOutputStream());

    }

    protected void handleFileUploadException(final FileUploadException e) throws ServletException {
        // suppress logging because it can be caught by logging filter
        //log.error("Failed to parse multipart request", e);
        throw new ServletException("Failed to upload the file.", e);
    }

    // ===================================================================================

    /** The key of the message: Error Count */
    public static final String LABELS_ERROR_COUNT = "{labels.errorCount}";

    /** The key of the message: Error Log */
    public static final String LABELS_ERROR_LOG = "{labels.errorLog}";

    /** The key of the message: Error Name */
    public static final String LABELS_ERROR_NAME = "{labels.errorName}";

                            } else if (logger.isWarnEnabled()) {
                                logger.warn(msg);
                            } else if (logger.isErrorEnabled()) {
                                logger.error(msg);
                            }
                        }
                    } catch (final Exception e) {
                        logger.warn(e.getLocalizedMessage());
                    }

                }
            }

            @Override
            public void onFailure(final Exception e) {
                logger.error(() -> "Failed to refresh " + stream(indices).get(stream -> stream.collect(Collectors.joining(", "))), e);
            }
        });

    }

    public void flush(final String... indices) {