public void checkAndNotify(){
  for (  FileAlterationListener listener : listeners) {
    listener.onStart(this);
  }
  File rootFile=rootEntry.getFile();
  if (rootFile.exists()) {
    checkAndNotify(rootEntry,rootEntry.getChildren(),listFiles(rootFile));
  }
 else   if (rootEntry.isExists()) {
    checkAndNotify(rootEntry,rootEntry.getChildren(),FileUtils.EMPTY_FILE_ARRAY);
  }
 else {
  }
  for (  FileAlterationListener listener : listeners) {
    listener.onStop(this);
  }
}

public void checkAndNotify ( ) { for ( FileAlterationListener listener : listeners ) { listener . onStart ( this ) ; } File rootFile = rootEntry . getFile ( ) ; if ( rootFile . exists ( ) ) { checkAndNotify ( rootEntry , rootEntry . getChildren ( ) , listFiles ( rootFile ) ) ; } else if ( rootEntry . isExists ( ) ) { checkAndNotify ( rootEntry , rootEntry . getChildren ( ) , FileUtils . EMPTY_FILE_ARRAY ) ; } else { } for ( FileAlterationListener listener : listeners ) { listener . onStop ( this ) ; } }
check whether the file and its chlidren have been created , modified or deleted .
