checks if the given file is being persisted . concode_field_sep Set<Long> mPersistedFiles concode_elem_sep Object mLock concode_elem_sep UnderFileSystem mUfs concode_elem_sep BlockWorker mBlockWorker concode_elem_sep RateLimiter mPersistenceRateLimiter concode_elem_sep Map<Long,Map<Long,Long>> mPersistingInProgressFiles concode_elem_sep Logger LOG concode_field_sep String prepareUfsFilePath concode_elem_sep void clearPersistedFiles concode_elem_sep boolean fileExistsInUfs concode_elem_sep boolean needPersistence concode_elem_sep void persistFile concode_elem_sep void addPersistedFile concode_elem_sep boolean isFilePersisted concode_elem_sep void lockBlocks concode_elem_sep List<Long> getPersistedFiles