Package org.apache.lucene.search

Class DocValuesFieldExistsQuery

java.lang.Object

org.apache.lucene.search.Query

org.apache.lucene.search.DocValuesFieldExistsQuery

public final class DocValuesFieldExistsQuery
extends Query

A Query that matches documents that have a value for a given field as reported by doc values iterators.

Constructor Summary

Constructors

Constructor	Description
DocValuesFieldExistsQuery(String field)	Create a query that will match documents which have a value for the given field.

Method Summary

Modifier and Type	Method	Description
Weight	createWeight(IndexSearcher searcher, ScoreMode scoreMode, float boost)	Expert: Constructs an appropriate Weight implementation for this query.
boolean	equals(Object other)	Override and implement query instance equivalence properly in a subclass.
static DocIdSetIterator	getDocValuesDocIdSetIterator(String field, LeafReader reader)	Returns a DocIdSetIterator from the given field or null if the field doesn't exist in the reader or if the reader has no doc values for the field.
String	getField()
int	hashCode()	Override and implement query hash code properly in a subclass.
Query	rewrite(IndexReader reader)	Expert: called to re-write queries into primitive queries.
String	toString(String field)	Prints a query to a string, with field assumed to be the default field and omitted.
void	visit(QueryVisitor visitor)	Recurse through the query tree, visiting any child queries

Methods inherited from class org.apache.lucene.search.Query

classHash, sameClassAs, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Details

DocValuesFieldExistsQuery

public DocValuesFieldExistsQuery(String field)

Create a query that will match documents which have a value for the given field.

Method Details

getField

public String getField()

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:

• Query.equals(Object)

toString

public String toString(String field)

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

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

Parameters:

visitor - a QueryVisitor to be called by each query in the tree

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.

Overrides:

rewrite in class Query

Throws:

IOException

createWeight

public Weight createWeight(IndexSearcher searcher,
 ScoreMode scoreMode,
 float boost)

Description copied from class: Query

Expert: Constructs an appropriate Weight implementation for this query.

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

Overrides:

createWeight in class Query

scoreMode - How the produced scorers will be consumed.

boost - The boost that is propagated by the parent queries.

getDocValuesDocIdSetIterator

public static DocIdSetIterator getDocValuesDocIdSetIterator(String field,
 LeafReader reader)
                                                     throws IOException

Returns a DocIdSetIterator from the given field or null if the field doesn't exist in the reader or if the reader has no doc values for the field.

Throws:

IOException