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

Class JoinStream

java.lang.Object

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

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

All Implemented Interfaces:

Closeable, Serializable, AutoCloseable, Expressible, MapSerializable, MapWriter

Direct Known Subclasses:

BiJoinStream

public abstract class JoinStream
extends TupleStream
implements Expressible

Defines a JoinStream which can hold N streams, all joined with the same equalitor

See Also:

Serialized Form

Nested Class Summary

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

MapWriter.EntryWriter

Field Summary

Fields

Modifier and Type	Field and Description
protected StreamEqualitor	eq

Constructor Summary

Constructors

Constructor and Description
JoinStream(StreamEqualitor eq, TupleStream first, TupleStream second, TupleStream... others)
JoinStream(StreamExpression expression, StreamFactory factory)

Method Summary

Modifier and Type	Method and Description
List<TupleStream>	children()
void	close()
int	getCost()
PushBackStream	getStream(int idx)
protected boolean	isValidTupleOrder()
protected Tuple	loadEqualTupleGroup(PushBackStream stream, LinkedList<Tuple> group, StreamComparator groupComparator) Given the stream, start from beginning and load group with all tuples that are equal to the first in stream (including the first one in the stream).
void	open()
void	setStreamContext(StreamContext context)
Explanation	toExplanation(StreamFactory factory) Returns an explanation about the stream object
StreamExpression	toExpression(StreamFactory factory)
protected abstract void	validateTupleOrder()

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

getShards, getSlices, getStreamNodeId, getStreamSort, read, 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.common.MapWriter

toMap

Field Detail

eq

protected StreamEqualitor eq

Constructor Detail

JoinStream

public JoinStream(StreamEqualitor eq,
                  TupleStream first,
                  TupleStream second,
                  TupleStream... others)

JoinStream

public JoinStream(StreamExpression expression,
                  StreamFactory factory)
           throws IOException

Throws:

IOException

Method Detail

validateTupleOrder

protected abstract void validateTupleOrder()
                                    throws IOException

Throws:

IOException

toExpression

public StreamExpression toExpression(StreamFactory factory)
                              throws IOException

Specified by:

toExpression in interface Expressible

Throws:

IOException

toExplanation

public Explanation toExplanation(StreamFactory factory)
                          throws IOException

Description copied from interface: Expressible

Returns an explanation about the stream object

Specified by:

toExplanation in interface Expressible

Specified by:

toExplanation in class TupleStream

Parameters:

factory - Stream factory for this, contains information about the function name

Returns:

Explanation about this stream object containing explanations of any child stream objects

Throws:

IOException - throw on any error

setStreamContext

public void setStreamContext(StreamContext context)

Specified by:

setStreamContext in class TupleStream

open

public void open()
          throws IOException

Specified by:

open in class TupleStream

Throws:

IOException

close

public void close()
           throws IOException

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Specified by:

close in class TupleStream

Throws:

IOException

children

public List<TupleStream> children()

Specified by:

children in class TupleStream

getStream

public PushBackStream getStream(int idx)

isValidTupleOrder

protected boolean isValidTupleOrder()

loadEqualTupleGroup

protected Tuple loadEqualTupleGroup(PushBackStream stream,
                                    LinkedList<Tuple> group,
                                    StreamComparator groupComparator)
                             throws IOException

Given the stream, start from beginning and load group with all tuples that are equal to the first in stream (including the first one in the stream). All matched tuples are removed from the stream. Result is at least one tuple will be read from the stream and 0 or more tuples will exist in the group. If the first tuple is EOF then the group will have 0 items. Else it will have at least one item. The first group member is returned.

Parameters:

group - - should be empty

Throws:

IOException

getCost

public int getCost()

Overrides:

getCost in class TupleStream