Class TermInSetQuery

  • All Implemented Interfaces:

    public class TermInSetQuery
    extends Query
    implements Accountable
    Specialization for a disjunction over many terms that behaves like a ConstantScoreQuery over a BooleanQuery containing only BooleanClause.Occur.SHOULD clauses.

    For instance in the following example, both q1 and q2 would yield the same scores:

     Query q1 = new TermInSetQuery("field", new BytesRef("foo"), new BytesRef("bar"));
     BooleanQuery bq = new BooleanQuery();
     bq.add(new TermQuery(new Term("field", "foo")), Occur.SHOULD);
     bq.add(new TermQuery(new Term("field", "bar")), Occur.SHOULD);
     Query q2 = new ConstantScoreQuery(bq);

    When there are few terms, this query executes like a regular disjunction. However, when there are many terms, instead of merging iterators on the fly, it will populate a bit set with matching docs and return a Scorer over this bit set.

    NOTE: This query produces scores that are equal to its boost

    • Method Detail

      • rewrite

        public Query rewrite​(IndexReader reader)
                      throws IOException
        Description copied from class: Query
        Expert: called to re-write queries into primitive queries. For example, a PrefixQuery will be rewritten into a BooleanQuery that consists of TermQuerys.

        Callers are expected to call rewrite multiple times if necessary, until the rewritten query is the same as the original query.

        rewrite in class Query
        See Also:
      • visit

        public void visit​(QueryVisitor visitor)
        Description copied from class: Query
        Recurse through the query tree, visiting any child queries
        Specified by:
        visit in class Query
        visitor - a QueryVisitor to be called by each query in the tree
      • equals

        public boolean equals​(Object other)
        Description copied from class: Query
        Override and implement query instance equivalence properly in a subclass. This is required so that QueryCache works properly.

        Typically a query will be equal to another only if it's an instance of the same class and its document-filtering properties are identical that other instance. Utility methods are provided for certain repetitive code.

        Specified by:
        equals in class Query
        See Also:
        Query.sameClassAs(Object), Query.classHash()
      • hashCode

        public int hashCode()
        Description copied from class: Query
        Override and implement query hash code properly in a subclass. This is required so that QueryCache works properly.
        Specified by:
        hashCode in class Query
        See Also:
      • getTermData

        public PrefixCodedTerms getTermData()
        Returns the terms wrapped in a PrefixCodedTerms.
      • toString

        public String toString​(String defaultField)
        Description copied from class: Query
        Prints a query to a string, with field assumed to be the default field and omitted.
        Specified by:
        toString in class Query
      • ramBytesUsed

        public long ramBytesUsed()
        Description copied from interface: Accountable
        Return the memory usage of this object in bytes. Negative values are illegal.
        Specified by:
        ramBytesUsed in interface Accountable
      • createWeight

        public Weight createWeight​(IndexSearcher searcher,
                                   ScoreMode scoreMode,
                                   float boost)
                            throws IOException
        Description copied from class: Query
        Expert: Constructs an appropriate Weight implementation for this query.

        Only implemented by primitive queries, which re-write to themselves.

        createWeight in class Query
        scoreMode - How the produced scorers will be consumed.
        boost - The boost that is propagated by the parent queries.