Package org.apache.solr.client.solrj.io.stream

Class OuterHashJoinStream

java.lang.Object

org.apache.solr.client.solrj.io.stream.TupleStream

org.apache.solr.client.solrj.io.stream.HashJoinStream

org.apache.solr.client.solrj.io.stream.OuterHashJoinStream

All Implemented Interfaces:

Closeable, Serializable, AutoCloseable, Expressible, org.apache.solr.common.MapSerializable, org.apache.solr.common.MapWriter, org.apache.solr.common.NavigableObject, org.noggit.JSONWriter.Writable

public class OuterHashJoinStream
extends HashJoinStream
implements Expressible

Takes two streams (fullStream and hashStream) and joins them similar to an LeftOuterJoinStream. The difference in a OuterHashJoinStream is that the tuples in the hashStream will all be read and hashed when this stream is opened. This provides a few optimizations iff the hashStream has a relatively small number of documents. The difference between this and a HashJoinStream is that a tuple in the fullStream will be returned even if it doesn't have any matching tuples in the hashStream. You are expected to provide a set of fields for which the hash will be calculated from. If a tuple from the hashStream does not contain a value (ie, null) for one of the fields the hash is being computed on then that tuple will not be considered a match to anything. If a tuple from the fullStream does not contain a value (ie, null) for one of the fields the hash is being computed on then that tuple will be returned without any joined tuples from the hashStream

Since:

6.0.0

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.solr.client.solrj.io.stream.TupleStream

TupleStream.IgnoreException

Nested classes/interfaces inherited from interface org.apache.solr.common.MapWriter

org.apache.solr.common.MapWriter.EntryWriter

Field Summary

Fields inherited from class org.apache.solr.client.solrj.io.stream.HashJoinStream

fullStream, hashedTuples, hashStream, leftHashOn, rightHashOn, workingFullHash, workingFullTuple, workngHashSetIdx

Fields inherited from interface org.apache.solr.common.MapWriter

EMPTY

Constructor Summary

Constructors

Constructor	Description
OuterHashJoinStream(StreamExpression expression, StreamFactory factory)
OuterHashJoinStream(TupleStream fullStream, TupleStream hashStream, List<String> hashOn)

Method Summary

Modifier and Type	Method	Description
Tuple	read()
StreamExpression	toExpression(StreamFactory factory)

Methods inherited from class org.apache.solr.client.solrj.io.stream.HashJoinStream

children, close, computeHash, getCost, getStreamSort, open, setStreamContext, toExplanation

Methods inherited from class org.apache.solr.client.solrj.io.stream.TupleStream

getShards, getShards, getStreamNodeId, writeMap

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.apache.solr.client.solrj.io.stream.expr.Expressible

toExplanation

Methods inherited from interface org.apache.solr.common.MapWriter

append, jsonStr, toMap, write

Methods inherited from interface org.apache.solr.common.NavigableObject

_forEachEntry, _forEachEntry, _forEachEntry, _get, _get, _getStr, _getStr, _size

Constructor Detail

OuterHashJoinStream

public OuterHashJoinStream(TupleStream fullStream,
                           TupleStream hashStream,
                           List<String> hashOn)
                    throws IOException

Throws:

IOException

OuterHashJoinStream

public OuterHashJoinStream(StreamExpression expression,
                           StreamFactory factory)
                    throws IOException

Throws:

IOException

Method Detail

toExpression

public StreamExpression toExpression(StreamFactory factory)
                              throws IOException

Specified by:

toExpression in interface Expressible

Overrides:

toExpression in class HashJoinStream

Throws:

IOException

read

public Tuple read()
           throws IOException

Overrides:

read in class HashJoinStream

Throws:

IOException