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

Class AbstractFederatedServiceResolver

java.lang.Object

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

All Implemented Interfaces:

FederatedServiceResolver

Direct Known Subclasses:

DelegateFederatedServiceResolver, SPARQLServiceResolver

public abstract class AbstractFederatedServiceResolver
extends Object
implements FederatedServiceResolver

Base class for FederatedServiceResolver which takes care for lifecycle management of produced FederatedServices.

Specific implementation can implement createService(String).

Author:

Andreas Schwarte

Field Summary

Fields

Modifier and Type	Field	Description
protected Map<String,FederatedService>	endpointToService	Map service URL to the corresponding initialized FederatedService

Constructor Summary

Constructors

Constructor	Description
AbstractFederatedServiceResolver()

Method Summary

Modifier and Type	Method	Description
protected abstract FederatedService	createService(String serviceUrl)	Create a new FederatedService for the given serviceUrl.
FederatedService	getService(String serviceUrl)	Retrieve the FederatedService registered for serviceUrl.
boolean	hasService(String serviceUrl)	Verify if a registered FederatedService exists for the given serviceUrul.
void	registerService(String serviceUrl, FederatedService service)	Register the specified service to evaluate SERVICE expressions for the given url.
void	shutDown()
void	unregisterAll()
void	unregisterService(String serviceUrl)	Unregister a service registered to serviceURl

Methods inherited from class java.lang.Object

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

Field Details

endpointToService

protected Map<String,FederatedService> endpointToService

Map service URL to the corresponding initialized FederatedService

Constructor Details

AbstractFederatedServiceResolver

public AbstractFederatedServiceResolver()

Method Details

registerService

public void registerService(String serviceUrl,
 FederatedService service)

Register the specified service to evaluate SERVICE expressions for the given url.

Parameters:

serviceUrl -

service -

unregisterService

public void unregisterService(String serviceUrl)

Unregister a service registered to serviceURl

Parameters:

serviceUrl -

getService

public FederatedService getService(String serviceUrl)
                            throws QueryEvaluationException

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

Specified by:

getService in interface FederatedServiceResolver

Parameters:

serviceUrl - locator for the federation service

Returns:

the FederatedService, created fresh if necessary

Throws:

QueryEvaluationException

hasService

public boolean hasService(String serviceUrl)

Verify if a registered FederatedService exists for the given serviceUrul.

Parameters:

serviceUrl - locator for the federation service.

Returns:

true iff the FederatedService has been registered, false otherwise.

createService

protected abstract FederatedService createService(String serviceUrl)
                                           throws QueryEvaluationException

Create a new FederatedService for the given serviceUrl. This method is invoked, if no FederatedService has been created yet for the serviceUrl.

Parameters:

serviceUrl - the service IRI

Returns:

a non-null FederatedService

Throws:

QueryEvaluationException

unregisterAll

public void unregisterAll()

shutDown

public void shutDown()