org.apache.lucene.search.join

Class ParentChildrenBlockJoinQuery

java.lang.Object

org.apache.lucene.search.Query

org.apache.lucene.search.join.ParentChildrenBlockJoinQuery

public class ParentChildrenBlockJoinQuery
extends Query

A query that returns all the matching child documents for a specific parent document indexed together in the same block. The provided child query determines which matching child doc is being returned.

Field Summary

Fields

Modifier and Type	Field and Description
private Query	childQuery
private int	parentDocId
private BitSetProducer	parentFilter

Constructor Summary

Constructors

Constructor and Description
ParentChildrenBlockJoinQuery(BitSetProducer parentFilter, Query childQuery, int parentDocId) Creates a ParentChildrenBlockJoinQuery instance

Method Summary

Modifier and Type	Method and Description
Weight	createWeight(IndexSearcher searcher, ScoreMode scoreMode, float boost) Expert: Constructs an appropriate Weight implementation for this query.
boolean	equals(java.lang.Object obj) Override and implement query instance equivalence properly in a subclass.
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.
java.lang.String	toString(java.lang.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

Field Detail

parentFilter

private final BitSetProducer parentFilter

childQuery

private final Query childQuery

parentDocId

private final int parentDocId

Constructor Detail

ParentChildrenBlockJoinQuery

public ParentChildrenBlockJoinQuery(BitSetProducer parentFilter,
                                    Query childQuery,
                                    int parentDocId)

Creates a ParentChildrenBlockJoinQuery instance

Parameters:

parentFilter - A filter identifying parent documents.

childQuery - A child query that determines which child docs are matching

parentDocId - The top level doc id of that parent to return children documents for

Method Detail

equals

public boolean equals(java.lang.Object obj)

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 java.lang.String toString(java.lang.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

Overrides:

visit in class Query

Parameters:

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

rewrite

public Query rewrite(IndexReader reader)
              throws java.io.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:

java.io.IOException

createWeight

public Weight createWeight(IndexSearcher searcher,
                           ScoreMode scoreMode,
                           float boost)
                    throws java.io.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.

Overrides:

createWeight in class Query

scoreMode - How the produced scorers will be consumed.

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

Throws:

java.io.IOException