BoostingQuery

Class Overview

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multiplied by the supplied "boost" parameter, so this should be less than 1 to achieve a demoting effect This code was originally made available here: [WWW] http://marc.theaimsgroup.com/?l=lucene-user&m=108058407130459&w=2 and is documented here: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

Summary

[Expand] Inherited Methods
From class org.apache.lucene.search.Query Object clone() Returns a clone of this query. Query combine(Query[] queries) Expert: called when re-writing queries under MultiSearcher. Weight createWeight(Searcher searcher) Expert: Constructs an appropriate Weight implementation for this query. boolean equals(Object obj) void extractTerms(Set<Term> terms) Expert: adds all terms occurring in this query to the terms set. float getBoost() Gets the boost for this clause. @Deprecated Similarity getSimilarity(Searcher searcher) This method is deprecated. Instead of using "runtime" subclassing/delegation, subclass the Weight instead. int hashCode() static Query mergeBooleanQueries(BooleanQuery... queries) Expert: merges the clauses of a set of BooleanQuery's into a single BooleanQuery. Query rewrite(IndexReader reader) Expert: called to re-write queries into primitive queries. void setBoost(float b) Sets the boost for this query clause to b. String toString() Prints a query to a string. abstract String toString(String field) Prints a query to a string, with field assumed to be the default field and omitted. Weight weight(Searcher searcher) Expert: Constructs and initializes a Weight for a top-level query.
From class java.lang.Object Object clone() boolean equals(Object arg0) void finalize() final Class<?> getClass() int hashCode() final void notify() final void notifyAll() String toString() final void wait() final void wait(long arg0, int arg1) final void wait(long arg0)