Class BoostingQuery

  • All Implemented Interfaces:
    Serializable, Cloneable

    public class BoostingQuery
    extends org.apache.lucene.search.Query
    The BoostingQuery class can be used to effectively demote results that match a given query. Unlike the "NOT" clause, this still selects documents that contain undesirable terms, but reduces their overall score: Query balancedQuery = new BoostingQuery(positiveQuery, negativeQuery, 0.01f); In this scenario the positiveQuery contains the mandatory, desirable criteria which is used to select all matching documents, and the negativeQuery contains the undesirable elements which are simply used to lessen the scores. Documents that match the negativeQuery have their score multiplied by the supplied "boost" parameter, so this should be less than 1 to achieve a demoting effect This code was originally made available here: [WWW] http://marc.theaimsgroup.com/?l=lucene-user&m=108058407130459&w=2 and is documented here: http://wiki.apache.org/lucene-java/CommunityContributions
    See Also:
    Serialized Form
    • Constructor Summary

      Constructors 
      Constructor Description
      BoostingQuery​(org.apache.lucene.search.Query match, org.apache.lucene.search.Query context, float boost)  
    • Constructor Detail

      • BoostingQuery

        public BoostingQuery​(org.apache.lucene.search.Query match,
                             org.apache.lucene.search.Query context,
                             float boost)
    • Method Detail

      • rewrite

        public org.apache.lucene.search.Query rewrite​(org.apache.lucene.index.IndexReader reader)
                                               throws IOException
        Overrides:
        rewrite in class org.apache.lucene.search.Query
        Throws:
        IOException
      • hashCode

        public int hashCode()
        Overrides:
        hashCode in class org.apache.lucene.search.Query
      • equals

        public boolean equals​(Object obj)
        Overrides:
        equals in class org.apache.lucene.search.Query
      • toString

        public String toString​(String field)
        Specified by:
        toString in class org.apache.lucene.search.Query