Class ToParentBlockJoinCollector

    • Constructor Detail

      • ToParentBlockJoinCollector

        public ToParentBlockJoinCollector​(Sort sort,
                                          int numParentHits,
                                          boolean trackScores,
                                          boolean trackMaxScore)
                                   throws IOException
        Throws:
        IOException
    • Method Detail

      • collect

        public void collect​(int parentDoc)
                     throws IOException
        Description copied from class: Collector
        Called once for every document matching a query, with the unbased document number.

        Note: This is called in an inner search loop. For good search performance, implementations of this method should not call Searcher.doc(int) or IndexReader.document(int) on every hit. Doing so can slow searches by an order of magnitude or more.

        Specified by:
        collect in class Collector
        Throws:
        IOException
      • acceptsDocsOutOfOrder

        public boolean acceptsDocsOutOfOrder()
        Description copied from class: Collector
        Return true if this collector does not require the matching docIDs to be delivered in int sort order (smallest to largest) to Collector.collect(int).

        Most Lucene Query implementations will visit matching docIDs in order. However, some queries (currently limited to certain cases of BooleanQuery) can achieve faster searching if the Collector allows them to deliver the docIDs out of order.

        Many collectors don't mind getting docIDs out of order, so it's important to return true here.

        Specified by:
        acceptsDocsOutOfOrder in class Collector
      • getTopGroups

        public TopGroups<Integer> getTopGroups​(ToParentBlockJoinQuery query,
                                               Sort withinGroupSort,
                                               int offset,
                                               int maxDocsPerGroup,
                                               int withinGroupOffset,
                                               boolean fillSortFields)
                                        throws IOException
        Return the TopGroups for the specified BlockJoinQuery. The groupValue of each GroupDocs will be the parent docID for that group. Note that the GroupDocs.totalHits, which would be the total number of child documents matching that parent, is not computed (will always be 0). Returns null if no groups matched.
        Throws:
        IOException