Package org.apache.lucene.search

Class FieldComparator.TermValComparator

  • Enclosing class:
    FieldComparator<T>
    public static final class FieldComparator.TermValComparator
extends FieldComparator<BytesRef>
    Sorts by field's natural Term sort order. All comparisons are done using BytesRef.compareTo, which is slow for medium to large result sets but possibly very fast for very small results sets.

    • Method Detail

      • compare

        public int compare​(int slot1,
                   int slot2)
        Description copied from class: FieldComparator
        Compare hit at slot1 with hit at slot2.
        Specified by:
        compare in class FieldComparator<BytesRef>
        Parameters:
        slot1 - first slot to compare
        slot2 - second slot to compare
        Returns:
        any N < 0 if slot2's value is sorted after slot1, any N > 0 if the slot2's value is sorted before slot1 and 0 if they are equal

      • compareBottom

        public int compareBottom​(int doc)
        Description copied from class: FieldComparator
        Compare the bottom of the queue with this doc. This will only invoked after setBottom has been called. This should return the same result as FieldComparator.compare(int,int)} as if bottom were slot1 and the new document were slot 2.

        For a search that hits many results, this method will be the hotspot (invoked by far the most frequently).

        Specified by:
        compareBottom in class FieldComparator<BytesRef>
        Parameters:
        doc - that was hit
        Returns:
        any N < 0 if the doc's value is sorted after the bottom entry (not competitive), any N > 0 if the doc's value is sorted before the bottom entry and 0 if they are equal.

      • copy

        public void copy​(int slot,
                 int doc)
        Description copied from class: FieldComparator
        This method is called when a new hit is competitive. You should copy any state associated with this document that will be required for future comparisons, into the specified slot.
        Specified by:
        copy in class FieldComparator<BytesRef>
        Parameters:
        slot - which slot to copy the hit to
        doc - docID relative to current reader

      • setNextReader

        public FieldComparator<BytesRef> setNextReader​(AtomicReaderContext context)
                                        throws java.io.IOException
        Description copied from class: FieldComparator
        Set a new AtomicReaderContext. All subsequent docIDs are relative to the current reader (you must add docBase if you need to map it to a top-level docID).
        Specified by:
        setNextReader in class FieldComparator<BytesRef>
        Parameters:
        context - current reader context
        Returns:
        the comparator to use for this segment; most comparators can just return "this" to reuse the same comparator across segments
        Throws:
        java.io.IOException - if there is a low-level IO error

      • compareValues

        public int compareValues​(BytesRef val1,
                         BytesRef val2)
        Description copied from class: FieldComparator
        Returns -1 if first is less than second. Default impl to assume the type implements Comparable and invoke .compareTo; be sure to override this method if your FieldComparator's type isn't a Comparable or if your values may sometimes be null
        Overrides:
        compareValues in class FieldComparator<BytesRef>

      • compareTop

        public int compareTop​(int doc)
        Description copied from class: FieldComparator
        Compare the top value with this doc. This will only invoked after setTopValue has been called. This should return the same result as FieldComparator.compare(int,int)} as if topValue were slot1 and the new document were slot 2. This is only called for searches that use searchAfter (deep paging).
        Specified by:
        compareTop in class FieldComparator<BytesRef>
        Parameters:
        doc - that was hit
        Returns:
        any N < 0 if the doc's value is sorted after the bottom entry (not competitive), any N > 0 if the doc's value is sorted before the bottom entry and 0 if they are equal.