org.eclipse.rdf4j.query.algebra.evaluation.federation

Interface FederatedServiceResolver

All Known Subinterfaces:

EvaluationStrategy

All Known Implementing Classes:

AbstractFederatedServiceResolver, DelegateFederatedServiceResolver, EvaluationStrategyImpl, ExtendedEvaluationStrategy, FederatedServiceResolverBase, FederatedServiceResolverImpl, FederationEvalStrategy, FederationStrategy, LimitedSizeEvaluationStrategy, SailFederationEvalStrategy, SimpleEvaluationStrategy, SparqlFederationEvalStrategy, SPARQLServiceResolver, StrictEvaluationStrategy, TupleFunctionEvaluationStrategy

public interface FederatedServiceResolver

The FederatedServiceResolver is used to manage a set of FederatedService instances, which are used to evaluate SERVICE expressions for particular service Urls.

Lookup can be done via the serviceUrl using the method getService(String).

Author:

Andreas Schwarte, James Leigh

Method Summary

Modifier and Type	Method and Description
FederatedService	getService(String serviceUrl) Retrieve the FederatedService registered for serviceUrl.

Method Detail

getService

FederatedService getService(String serviceUrl)
                     throws QueryEvaluationException

Retrieve the FederatedService registered for serviceUrl. If there is no service registered for serviceUrl, a new SPARQLFederatedService is created and registered.

Parameters:

serviceUrl - locator for the federation service

Returns:

the FederatedService, created fresh if necessary

Throws:

QueryEvaluationException - If there was an exception generated while retrieving the service.