http://lucene.apache.org/lucene-parent/lucene-queries: Lucene Queries Module (The Apache Software Foundation) 
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 * (the "License"); you may not use this file except in compliance with
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 *
 *     http://www.apache.org/licenses/LICENSE-2.0
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package org.apache.lucene.queries.intervals;

import org.apache.lucene.search.MatchesIterator;


An extension of MatchesIterator that allows the gaps from a wrapped IntervalIterator to be reported. This is necessary because MatchesIterator.getSubMatches() returns the submatches of all nested matches as a flat iterator, but IntervalIterator.gaps() only returns the gaps between its immediate sub-matches, so we can't calculate the latter using the former. 
/**
 * An extension of MatchesIterator that allows the gaps from a wrapped
 * IntervalIterator to be reported.
 *
 * This is necessary because {@link MatchesIterator#getSubMatches()} returns
 * the submatches of all nested matches as a flat iterator, but
 * {@link IntervalIterator#gaps()} only returns the gaps between its immediate
 * sub-matches, so we can't calculate the latter using the former.
 */
interface IntervalMatchesIterator extends MatchesIterator {

  
The number of top-level gaps inside the current match

/**
   * The number of top-level gaps inside the current match
   */
  int gaps();

}