private List<File> getAllDestFiles(File dest) {
        List<File> files = new ArrayList<File>();
        if (dest != null && dest.exists()) {
            listDestFiles(files, dest);
        }
        return files;
    }
private List < File > getAllDestFiles ( File dest ) { List < File > files = new ArrayList < File > ( ) ; if ( dest != null && dest . exists ( ) ) { listDestFiles ( files , dest ) ; } return files ; }
@param dest
@return