com.bigdata.bop.join

Class HashIndexOp

java.lang.Object

com.bigdata.bop.CoreBaseBOp

com.bigdata.bop.BOpBase

com.bigdata.bop.PipelineOp

com.bigdata.bop.join.HashIndexOpBase

com.bigdata.bop.join.HashIndexOp

All Implemented Interfaces:

BOp, ISingleThreadedOp, IPropertySet, Serializable, Cloneable

Direct Known Subclasses:

PipelinedHashIndexAndSolutionSetJoinOp

public class HashIndexOp
extends HashIndexOpBase

Operator builds a hash index from the source solutions. Once all source solutions have been indexed, the source solutions are output on the default sink. The set of variables to be copied to the sink may be restricted by an annotation.

The main use case for building a hash index is to execute a sub-group or sub-select. In both cases, the HashIndexOp is generated before we enter the sub-plan. All solutions from the hash index are then flowed into the sub-plan. Solutions emitted by the sub-plan are then re-integrated into the parent using a SolutionSetHashJoinOp.

There are two concrete implementations of this operator. One for the HTree and one for the JVM ConcurrentHashMap. Both hash index build operators have the same general logic, but differ in their specifics. Those differences are mostly encapsulated by the IHashJoinUtility interface. They also have somewhat different annotations, primarily because the HTree version needs access to the lexicon to setup its ivCache.

This operator is NOT thread-safe. It relies on the query engine to provide synchronization. The operator MUST be run on the query controller.

Author:

Bryan Thompson

See Also:

SolutionSetHashJoinOp, Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	HashIndexOp.Annotations
protected static class	HashIndexOp.ChunkTask

Nested classes/interfaces inherited from class com.bigdata.bop.join.HashIndexOpBase

HashIndexOpBase.ChunkTaskBase

Field Summary

Fields inherited from class com.bigdata.bop.CoreBaseBOp

DEFAULT_INITIAL_CAPACITY

Fields inherited from interface com.bigdata.bop.BOp

NOANNS, NOARGS

Constructor Summary

Constructors

Constructor and Description
HashIndexOp(BOp[] args, Map<String,Object> annotations) Shallow copy constructor.
HashIndexOp(BOp[] args, NV... annotations)
HashIndexOp(HashIndexOp op) Deep copy constructor.

Method Summary

Methods

Modifier and Type	Method and Description
protected HashIndexOpBase.ChunkTaskBase	createChunkTask(BOpContext<IBindingSet> context)

Methods inherited from class com.bigdata.bop.join.HashIndexOpBase

eval, newStats

Methods inherited from class com.bigdata.bop.PipelineOp

assertAtOnceJavaHeapOp, assertMaxParallelOne, getChunkCapacity, getChunkOfChunksCapacity, getChunkTimeout, getMaxMemory, getMaxParallel, isAtOnceEvaluation, isBlockedEvaluation, isLastPassRequested, isPipelinedEvaluation, isReorderSolutions, isSharedState

Methods inherited from class com.bigdata.bop.BOpBase

__replaceArg, _clearProperty, _set, _setProperty, annotations, annotationsCopy, annotationsEqual, annotationsRef, argIterator, args, argsCopy, arity, clearAnnotations, clearProperty, deepCopy, deepCopy, get, getProperty, setArg, setProperty, setUnboundProperty, toArray, toArray

Methods inherited from class com.bigdata.bop.CoreBaseBOp

annotationsEqual, annotationsToString, annotationsToString, annotationValueToString, checkArgs, clone, equals, getEvaluationContext, getId, getProperty, getRequiredProperty, hashCode, indent, isController, mutation, shortenName, toShortString, toString, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

HashIndexOp

public HashIndexOp(HashIndexOp op)

Deep copy constructor.

HashIndexOp

public HashIndexOp(BOp[] args,
           Map<String,Object> annotations)

Shallow copy constructor.

Parameters:

args -

annotations -

HashIndexOp

public HashIndexOp(BOp[] args,
           NV... annotations)

Method Detail

createChunkTask

protected HashIndexOpBase.ChunkTaskBase createChunkTask(BOpContext<IBindingSet> context)

Specified by:

createChunkTask in class HashIndexOpBase