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

Class PriorityStream

java.lang.Object

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

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

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 PriorityStream
extends TupleStream
implements Expressible

The priority function wraps two topics that represent high priority and low priority task queues. Each time the priority function is called it will check to see if there are any high priority tasks in the queue. If there are high priority tasks, then the high priority queue will be read until it returns the EOF Tuple.

If there are no tasks in the high priority queue, then the lower priority task queue will be opened and read until the EOF Tuple is returned.

The scheduler is designed to be wrapped by the executor function and a daemon function can be used to call the executor iteratively.

Since:

6.4.0

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 interface org.apache.solr.common.MapWriter

EMPTY

Constructor Summary

Constructors

Constructor	Description
PriorityStream(StreamExpression expression, StreamFactory factory)

Method Summary

Modifier and Type	Method	Description
List<TupleStream>	children()
void	close()
int	getCost()
StreamComparator	getStreamSort()
void	open()
Tuple	read()
void	setStreamContext(StreamContext streamContext)
Explanation	toExplanation(StreamFactory factory)	Returns an explanation about the stream object
StreamExpression	toExpression(StreamFactory factory)

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.common.MapWriter

jsonStr, toMap, write

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

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

Constructor Details

PriorityStream

public PriorityStream(StreamExpression expression,
 StreamFactory factory)
               throws IOException

Throws:

IOException

Method Details

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 streamContext)

Specified by:

setStreamContext in class TupleStream

children

public List<TupleStream> children()

Specified by:

children 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 AutoCloseable

Specified by:

close in interface Closeable

Specified by:

close in class TupleStream

Throws:

IOException

read

public Tuple read()
           throws IOException

Specified by:

read in class TupleStream

Throws:

IOException

getStreamSort

public StreamComparator getStreamSort()

Specified by:

getStreamSort in class TupleStream

getCost

public int getCost()

Overrides:

getCost in class TupleStream