question: private static synchronized File newFile ( String localPath ) { final File localFile = new File ( localPath ) ; if ( localFile . exists ( ) ) { localFile . delete ( ) ; } else { File parentFile = localFile . getParentFile ( ) ; if ( parentFile != null && ( parentFile . isDirectory ( ) || parentFile . mkdirs ( ) ) ) { try { localFile . createNewFile ( ) ; } catch ( IOException e ) { e . printStackTrace ( ) ; } } } return localFile ; }
target:  delete file if exists, create a new file and the parent dir.