Review

class MultiTermQueryWrapperFilter {
  /**
   * Expert: Return the number of unique terms visited during execution of the filter.
   * If there are many of them, you may consider using another filter type
   * or optimize your total term count in index.
   * <p>This method is not thread safe, be sure to only call it when no filter is running!
   * If you re-use the same filter instance for another
   * search, be sure to first reset the term counter
   * with {@link #clearTotalNumberOfTerms}.
   * @see #clearTotalNumberOfTerms
   */
  public int getTotalNumberOfTerms() {
    return query.getTotalNumberOfTerms();
  }

}