public boolean has(String url){
  final File transcriptDir=getTranscriptDir();
  if (transcriptDir == null)   return false;
  String hash=Sha1Util.SHA1(url);
  File file=new File(transcriptDir,hash);
  return file.exists();
}

public boolean has ( String url ) { final File transcriptDir = getTranscriptDir ( ) ; if ( transcriptDir == null ) return false ; String hash = Sha1Util . SHA1 ( url ) ; File file = new File ( transcriptDir , hash ) ; return file . exists ( ) ; }
this function checks if the file exists for that link
