public int validity() {
    int specifiedAttributes = 0;
    if (name != null)
      specifiedAttributes++;
    if (quality!= null)
      specifiedAttributes++;
    if (source != null)
      specifiedAttributes++;
    if (codec != null)
      specifiedAttributes++;
    if (releaseDate != null)
      specifiedAttributes++;
    if (seasonAndEpisode != null)
      specifiedAttributes++;
    return (specifiedAttributes*100/NEEDED_ATTRIBUTES);
  }