org.eclipse.rdf4j.federated.optimizer

Class DefaultFedXCostModel

java.lang.Object

org.eclipse.rdf4j.federated.optimizer.DefaultFedXCostModel

All Implemented Interfaces:

FedXCostModel

public class DefaultFedXCostModel
extends Object
implements FedXCostModel

Default implementation of the FedXCostModel

Author:

Andreas Schwarte

Field Summary

Fields

Modifier and Type	Field and Description
static DefaultFedXCostModel	INSTANCE

Constructor Summary

Constructors

Constructor and Description
DefaultFedXCostModel()

Method Summary

Modifier and Type	Method and Description
double	estimateCost(TupleExpr tupleExpr, Set<String> joinVars) Return the estimated cost for the given TupleExpr

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

INSTANCE

public static DefaultFedXCostModel INSTANCE

Constructor Detail

DefaultFedXCostModel

public DefaultFedXCostModel()

Method Detail

estimateCost

public double estimateCost(TupleExpr tupleExpr,
                           Set<String> joinVars)

Description copied from interface: FedXCostModel

Return the estimated cost for the given TupleExpr

Specified by:

estimateCost in interface FedXCostModel

Returns:

the cost associated to the tupleExpr