Package org.apache.lucene.facet.enhancements.association

Class AssociationsPayloadIterator

  • public class AssociationsPayloadIterator
extends Object
    Allows easy iteration over the associations payload, decoding and breaking it to (ordinal, value) pairs, stored in a hash.
    WARNING: This API is experimental and might change in incompatible ways in the next release.

    • Field Detail

      • ASSOCIATION_POSTING_TERM

        public static final org.apache.lucene.index.Term ASSOCIATION_POSTING_TERM
        Default Term for associations

      • NO_ASSOCIATION

        public static final long NO_ASSOCIATION
        The long-special-value returned for ordinals which have no associated int value. It is not in the int range of values making it a valid mark.
        See Also:
        Constant Field Values

    • Constructor Detail

      • AssociationsPayloadIterator

        public AssociationsPayloadIterator​(org.apache.lucene.index.IndexReader reader,
                                   String field)
                            throws IOException
        Construct a new association-iterator, initializing the inner payload iterator, with the supplied term and checking whether there are any associations within the given index
        Parameters:
        reader - a reader containing the postings to be iterated
        field - the field containing the relevant associations list term
        Throws:
        IOException

    • Method Detail

      • setNextDoc

        public boolean setNextDoc​(int docId)
                   throws IOException
        Skipping to the next document, fetching its associations & populating the map.
        Parameters:
        docId - document id to be skipped to
        Returns:
        true if the document contains associations and they were fetched correctly. false otherwise.
        Throws:
        IOException - on error

      • getAssociation

        public long getAssociation​(int ordinal)
        Get int association value for the given ordinal.
        The return is either an int value casted as long if the ordinal has an associated value. Otherwise the returned value would be NO_ASSOCIATION which is 'pure long' value (e.g not in the int range of values)
        Parameters:
        ordinal - for which the association value is requested
        Returns:
        the associated int value (encapsulated in a long) if the ordinal had an associated value, or NO_ASSOCIATION otherwise

      • getAssociatedOrdinals

        public IntIterator getAssociatedOrdinals()
        Get an iterator over the ordinals which has an association for the document set by setNextDoc(int).

      • hashCode

        public int hashCode()
        Overrides:
        hashCode in class Object