com.atlassian.greenhopper.service.lucene
Class LeftJoinQuery

java.lang.Object
  org.apache.lucene.search.Query
      com.atlassian.greenhopper.service.lucene.AbstractBitsetQuery
          com.atlassian.greenhopper.service.lucene.LeftJoinQuery

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable

public class LeftJoinQuery
extends AbstractBitsetQuery

TODO FIXUP this doco A query that performs a join between two indexes (left and right). This query can be used on the left index, and it selects documents in the left that match documents on the right. Documents on the left/right are "matched" using a fields with common values.

Specifically, this query will match documents in leftIndex, where leftdoc.leftField == rightdoc.rightField, and rightdoc is in rightDocIds;

This implementation doesn't do anything smart wrt to scoring at the moment.

Performance will be expected to be O(l+r); l is the number of Terms that match on the left, r is the number of terms that match on the right.

In the case where there is a 1-1 between left and right, best-case becomes O(1)

Author:

Matt Quail

See Also:

Serialized Form

Field Summary

Fields inherited from class com.atlassian.greenhopper.service.lucene.AbstractBitsetQuery

score

Constructor Summary

LeftJoinQuery(java.lang.String leftField, org.apache.lucene.index.IndexReader rightReader, java.lang.String rightField, java.util.BitSet rightDocIds)

LeftJoinQuery(java.lang.String leftField, RightJoinEnum rightEnum)

Method Summary

protected java.util.BitSet	computeBitset(org.apache.lucene.index.IndexReader reader)
protected java.lang.String	getFilterExplanation()
static BitSetRightJoinEnum	makeBitsetRightJoin(java.util.BitSet rightDocIds, org.apache.lucene.index.IndexReader rightReader, java.lang.String rightField)
static DocumentRightJoinEnum	makeDocumentRightEnum(java.util.BitSet rightDocIds, org.apache.lucene.index.IndexReader rightReader, java.lang.String rightField)
static RightJoinEnum	makeRightEnum(java.util.BitSet rightDocIds, org.apache.lucene.index.IndexReader rightReader, java.lang.String rightField)
java.lang.String	toString(java.lang.String field)

Methods inherited from class com.atlassian.greenhopper.service.lucene.AbstractBitsetQuery

getSimilarity, rewrite

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

clone, combine, createWeight, equals, extractTerms, getBoost, hashCode, mergeBooleanQueries, setBoost, toString, weight

Methods inherited from class java.lang.Object

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

Constructor Detail

LeftJoinQuery

public LeftJoinQuery(java.lang.String leftField,
                     org.apache.lucene.index.IndexReader rightReader,
                     java.lang.String rightField,
                     java.util.BitSet rightDocIds)

Parameters:

leftField - the match field on the left

rightReader - the Reader for the left index

rightField - the match field on the right

rightDocIds - the documents on the right to consider

LeftJoinQuery

public LeftJoinQuery(java.lang.String leftField,
                     RightJoinEnum rightEnum)

Method Detail

makeRightEnum

public static RightJoinEnum makeRightEnum(java.util.BitSet rightDocIds,
                                          org.apache.lucene.index.IndexReader rightReader,
                                          java.lang.String rightField)

makeBitsetRightJoin

public static BitSetRightJoinEnum makeBitsetRightJoin(java.util.BitSet rightDocIds,
                                                      org.apache.lucene.index.IndexReader rightReader,
                                                      java.lang.String rightField)

makeDocumentRightEnum

public static DocumentRightJoinEnum makeDocumentRightEnum(java.util.BitSet rightDocIds,
                                                          org.apache.lucene.index.IndexReader rightReader,
                                                          java.lang.String rightField)

computeBitset

protected java.util.BitSet computeBitset(org.apache.lucene.index.IndexReader reader)
                                  throws java.io.IOException

Specified by:

computeBitset in class AbstractBitsetQuery

Throws:

java.io.IOException

getFilterExplanation

protected java.lang.String getFilterExplanation()

Specified by:

getFilterExplanation in class AbstractBitsetQuery

toString

public java.lang.String toString(java.lang.String field)

Specified by:

toString in class org.apache.lucene.search.Query