final Path path = Paths.get(LaServletContextUtil.getServletContext().getRealPath(key));
                        if (Files.isRegularFile(path)) {
                            return Files.getLastModifiedTime(path).toMillis();
                        }
                    } catch (final Exception e) {
                        logger.debug("Failed to access {}", key, e);
                    }

        }

        @Override
        public FileVisitResult visitFile(final Path file, final BasicFileAttributes attrs) throws IOException {
            if (ComponentUtil.getSystemHelper().getCurrentTimeAsLong() - Files.getLastModifiedTime(file).toMillis() > expiry) {
                deletedFileList.add(file);
                if (deletedFileList.size() > maxPurgeSize) {
                    deleteFiles();
                }
            }