Class ConstantScoreQuery

A query that wraps another query or a filter and simply returns a constant score equal to the query boost for every document that matches the filter or query. For queries it therefore simply strips of all scores and returns a constant one.

Inheritance
object
Query
ConstantScoreQuery
Inherited Members
Namespace: Lucene.Net.Search
Assembly: Lucene.Net.dll
Syntax
public class ConstantScoreQuery : Query

Constructors

ConstantScoreQuery(Filter)

Wraps a Filter as a Query. The hits will get a constant score dependent on the boost factor of this query. If you simply want to strip off scores from a Query, no longer use new ConstantScoreQuery(new QueryWrapperFilter(query)), instead use ConstantScoreQuery(Query)!

Declaration
public ConstantScoreQuery(Filter filter)
Parameters
Type Name Description
Filter filter
Exceptions
Type Condition
ArgumentNullException

if filter is null.

ConstantScoreQuery(Query)

Strips off scores from the passed in Query. The hits will get a constant score dependent on the boost factor of this query.

Declaration
public ConstantScoreQuery(Query query)
Parameters
Type Name Description
Query query
Exceptions
Type Condition
ArgumentNullException

if query is null.

Fields

m_filter

A query that wraps another query or a filter and simply returns a constant score equal to the query boost for every document that matches the filter or query. For queries it therefore simply strips of all scores and returns a constant one.

Declaration
protected readonly Filter m_filter
Field Value
Type Description
Filter

m_query

A query that wraps another query or a filter and simply returns a constant score equal to the query boost for every document that matches the filter or query. For queries it therefore simply strips of all scores and returns a constant one.

Declaration
protected readonly Query m_query
Field Value
Type Description
Query

Properties

Filter

Returns the encapsulated filter, returns null if a query is wrapped.

Declaration
public virtual Filter Filter { get; }
Property Value
Type Description
Filter

Query

Returns the encapsulated query, returns null if a filter is wrapped.

Declaration
public virtual Query Query { get; }
Property Value
Type Description
Query

Methods

CreateWeight(IndexSearcher)

Expert: Constructs an appropriate Weight implementation for this query.

Only implemented by primitive queries, which re-write to themselves.
Declaration
public override Weight CreateWeight(IndexSearcher searcher)
Parameters
Type Name Description
IndexSearcher searcher
Returns
Type Description
Weight
Overrides

Equals(object)

Determines whether the specified object is equal to the current object.

Declaration
public override bool Equals(object o)
Parameters
Type Name Description
object o
Returns
Type Description
bool

true if the specified object is equal to the current object; otherwise, false.
Overrides

ExtractTerms(ISet<Term>)

Expert: adds all terms occurring in this query to the terms set. Only works if this query is in its rewritten (Rewrite(IndexReader)) form.

Declaration
public override void ExtractTerms(ISet<Term> terms)
Parameters
Type Name Description
ISet<Term> terms
Overrides
Exceptions
Type Condition
InvalidOperationException

If this query is not yet rewritten

GetHashCode()

Serves as the default hash function.

Declaration
public override int GetHashCode()
Returns
Type Description
int

A hash code for the current object.
Overrides

Rewrite(IndexReader)

Expert: called to re-write queries into primitive queries. For example, a PrefixQuery will be rewritten into a BooleanQuery that consists of TermQuerys.

Declaration
public override Query Rewrite(IndexReader reader)
Parameters
Type Name Description
IndexReader reader
Returns
Type Description
Query
Overrides

ToString(string)

Prints a query to a string, with field assumed to be the default field and omitted.

Declaration
public override string ToString(string field)
Parameters
Type Name Description
string field
Returns
Type Description
string
Overrides