com.bigdata.bop.solutions
Class JVMDistinctBindingSetsOp

java.lang.Object
  com.bigdata.bop.CoreBaseBOp
      com.bigdata.bop.BOpBase
          com.bigdata.bop.PipelineOp
              com.bigdata.bop.solutions.JVMDistinctBindingSetsOp

All Implemented Interfaces:

BOp, IPropertySet, Serializable, Cloneable

public class JVMDistinctBindingSetsOp
extends PipelineOp

A pipelined DISTINCT operator based on a hash table.

Note: This implementation is a pipelined operator which inspects each chunk of solutions as they arrive and those solutions which are distinct for each chunk are passed on. It uses a ConcurrentMap and is thread-safe. TODO Look into reconciling this class with JVMHashJoinUtility. However, note that this implementation is thread-safe and uses a ConcurrentMap. It may be better to leave things as they are since this implementation may be more efficient for the special case which it handles.

Version:

$Id: DistinctElementFilter.java 3466 2010-08-27 14:28:04Z thompsonbry $

Author:

Bryan Thompson

See Also:

Serialized Form

Nested Class Summary

static interface

JVMDistinctBindingSetsOp.Annotations

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

JVMDistinctBindingSetsOp(BOp[] args, Map<String,Object> annotations)
Required shallow copy constructor.

JVMDistinctBindingSetsOp(BOp[] args, NV... annotations)

JVMDistinctBindingSetsOp(JVMDistinctBindingSetsOp op)
Required deep copy constructor.

Method Summary

FutureTask<Void>	eval(BOpContext<IBindingSet> context) Return a FutureTask which computes the operator against the evaluation context.
int	getConcurrencyLevel()
int	getInitialCapacity()
float	getLoadFactor()
IVariable<?>[]	getVariables()

Methods inherited from class com.bigdata.bop.PipelineOp

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

Methods inherited from class com.bigdata.bop.BOpBase

_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, checkArgs, clone, equals, getEvaluationContext, getId, getProperty, getRequiredProperty, hashCode, indent, isController, toShortString, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

JVMDistinctBindingSetsOp

public JVMDistinctBindingSetsOp(JVMDistinctBindingSetsOp op)

Required deep copy constructor.

JVMDistinctBindingSetsOp

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

Required shallow copy constructor.

JVMDistinctBindingSetsOp

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

Method Detail

getInitialCapacity

public int getInitialCapacity()

See Also:

HashMapAnnotations.INITIAL_CAPACITY

getLoadFactor

public float getLoadFactor()

See Also:

HashMapAnnotations.LOAD_FACTOR

getConcurrencyLevel

public int getConcurrencyLevel()

See Also:

ConcurrentHashMapAnnotations.CONCURRENCY_LEVEL

getVariables

public IVariable<?>[] getVariables()

See Also:

DistinctAnnotations.VARIABLES

eval

public FutureTask<Void> eval(BOpContext<IBindingSet> context)

Description copied from class: PipelineOp

Return a FutureTask which computes the operator against the evaluation context. The caller is responsible for executing the FutureTask (this gives them the ability to hook the completion of the computation).

Specified by:

eval in class PipelineOp

Parameters:

context - The evaluation context.

Returns:

The FutureTask which will compute the operator's evaluation.