com.bigdata.rdf.lexicon

Class LexPredicate

java.lang.Object

com.bigdata.bop.CoreBaseBOp

com.bigdata.bop.BOpBase

com.bigdata.bop.AbstractAccessPathOp<E>

com.bigdata.bop.ap.Predicate<BigdataValue>

com.bigdata.rdf.lexicon.LexPredicate

All Implemented Interfaces:

BOp, IPredicate<BigdataValue>, IPropertySet, Serializable, Cloneable

public class LexPredicate
extends Predicate<BigdataValue>

A lex(BigdataValue,IV) predicate used for querying the LexiconRelation's TERMS index.

Version:

$Id$

Author:

Mike Personick

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class com.bigdata.bop.ap.Predicate

Predicate.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

Constructors

Constructor and Description
LexPredicate(BOp[] args, Map<String,Object> anns) Required shallow copy constructor.
LexPredicate(BOp[] args, NV... anns) Variable argument version of the shallow copy constructor.
LexPredicate(LexPredicate op) Constructor required for com.bigdata.bop.BOpUtility#deepCopy(FilterNode).

Method Summary

Methods

Modifier and Type	Method and Description
LexPredicate	asBound(IBindingSet bindingSet) Strengthened return type.
LexPredicate	clone() Overridden to provide a fast path clone().
static LexPredicate	forwardInstance(String relationName, long timestamp, IVariableOrConstant<BigdataValue> term, IVariable<IV> var) Simplified forward lookup ctor.
IVariableOrConstant<IV>	iv() Return the IV at index position .
static LexPredicate	reverseInstance(String relationName, long timestamp, IVariable<BigdataValue> var, IVariableOrConstant<IV> term) Simplified reverse lookup ctor.
IVariableOrConstant<BigdataValue>	term() Return the BigdataValue at index position .

Methods inherited from class com.bigdata.bop.ap.Predicate

_asBound, addAccessPathFilter, addIndexLocalFilter, asBound, asBound, checkArgs, clearAnnotations, get, get, getAccessPathExpander, getAccessPathFilter, getIndexLocalFilter, getKeyOrder, getOnlyRelationName, getPartitionId, getRelationCount, getRelationName, getTimestamp, getVariableCount, getVariableCount, isFullyBound, isOptional, isRemoteAccessPath, range, setArg, setBOpId, setPartitionId, setRelationName, setTimestamp, toString, toString

Methods inherited from class com.bigdata.bop.BOpBase

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

Methods inherited from class com.bigdata.bop.CoreBaseBOp

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

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.bigdata.bop.IPredicate

equals, hashCode

Methods inherited from interface com.bigdata.bop.BOp

annotations, argIterator, args, arity, getEvaluationContext, getId, getProperty, getRequiredProperty, isController, setProperty, toArray, toArray, toShortString, toString

Methods inherited from interface cutthecrap.utils.striterators.IPropertySet

getProperty

Constructor Detail

LexPredicate

public LexPredicate(BOp[] args,
            NV... anns)

Variable argument version of the shallow copy constructor.

LexPredicate

public LexPredicate(BOp[] args,
            Map<String,Object> anns)

Required shallow copy constructor.

LexPredicate

public LexPredicate(LexPredicate op)

Constructor required for com.bigdata.bop.BOpUtility#deepCopy(FilterNode).

Method Detail

forwardInstance

public static LexPredicate forwardInstance(String relationName,
                           long timestamp,
                           IVariableOrConstant<BigdataValue> term,
                           IVariable<IV> var)

Simplified forward lookup ctor. Use this ctor to lookup an IV from a BigdataValue.

Parameters:

relationName - the namespace of the lexicon relation

timestamp - The timestamp of the view to read on. This should be the same as the timestamp associated with the view of the triple store except for a full read/write transaction. Since all writes on the lexicon are unisolated, a full read/write transaction must use the ITx.UNISOLATED view of the lexicon in order to ensure that any writes it performs will be visible.

var - The variable on which the IV will be bound when we read on the access path.

term - the term to resolve using forward lookup (term2id)

reverseInstance

public static LexPredicate reverseInstance(String relationName,
                           long timestamp,
                           IVariable<BigdataValue> var,
                           IVariableOrConstant<IV> term)

Simplified reverse lookup ctor. Use this ctor to lookup a BigdataValue from an IV.

Parameters:

relationName - the namespace of the lexicon relation

timestamp - The timestamp of the view to read on. This should be the same as the timestamp associated with the view of the triple store except for a full read/write transaction. Since all writes on the lexicon are unisolated, a full read/write transaction must use the ITx.UNISOLATED view of the lexicon in order to ensure that any writes it performs will be visible.

var - The variable on which the Value will be bound when we read on the access path.

term - the term to resolve using reverse lookup (id2term)

clone

public LexPredicate clone()

Description copied from class: Predicate

Overridden to provide a fast path clone(). This avoids a constructor lookup via reflection in favor of simply creating a new Predicate instance. However, subclasses MUST override this method. This change was introduced on 11/17/2011 when a profiler showed a 13% of all time related to a join intensive process in CoreBaseBOp.clone() using reflection to make a copy of an Predicate.asBound(IBindingSet) predicate.

Specified by:

clone in interface BOp

Overrides:

clone in class Predicate<BigdataValue>

term

public final IVariableOrConstant<BigdataValue> term()

Return the BigdataValue at index position .

iv

public final IVariableOrConstant<IV> iv()

Return the IV at index position .

asBound

public LexPredicate asBound(IBindingSet bindingSet)

Strengthened return type.

Fast path for as-bound.

This reuses the annotations map since we know that the annotations will not be changed by Predicate.asBound(IBindingSet). That provides a significant reduction in heap churn.

Specified by:

asBound in interface IPredicate<BigdataValue>

Overrides:

asBound in class Predicate<BigdataValue>

Parameters:

bindingSet - The binding set.

Returns:

The as-bound IPredicate -or- null if the IPredicate can not be unified with the IBindingSet.

See Also:

(RDR query does too much work)