Package org.eclipse.rdf4j.federated.evaluation

Class SparqlTripleSource

java.lang.Object

org.eclipse.rdf4j.federated.evaluation.TripleSourceBase

org.eclipse.rdf4j.federated.evaluation.SparqlTripleSource

All Implemented Interfaces:

TripleSource

public class SparqlTripleSource
extends TripleSourceBase

A triple source to be used for (remote) SPARQL endpoints.

This triple source supports the SparqlEndpointConfiguration for defining whether ASK queries are to be used for source selection.

The query result of TripleSourceBase.getStatements(String, BindingSet, FilterValueExpr, QueryInfo) is wrapped in a ConsumingIteration to avoid blocking behavior..

Author:

Andreas Schwarte

Nested Class Summary

Nested classes/interfaces inherited from class org.eclipse.rdf4j.federated.evaluation.TripleSourceBase

TripleSourceBase.ConnectionOperation<T>, TripleSourceBase.ResultHolder<T>

Field Summary

Fields inherited from class org.eclipse.rdf4j.federated.evaluation.TripleSourceBase

endpoint, federationContext, monitoringService

Method Summary

Modifier and Type	Method	Description
CloseableIteration<Statement>	getStatements(Resource subj, IRI pred, Value obj, QueryInfo queryInfo, Resource... contexts)	Return the statements matching the given pattern as a Statement iteration.
CloseableIteration<BindingSet>	getStatements(StatementPattern stmt, BindingSet bindings, FilterValueExpr filterExpr, QueryInfo queryInfo)	Evaluate the query expression on the provided endpoint.
CloseableIteration<BindingSet>	getStatements(TupleExpr preparedQuery, BindingSet bindings, FilterValueExpr filterExpr, QueryInfo queryInfo)	Evaluate the prepared query in its internal representation on the provided endpoint.
boolean	hasStatements(ExclusiveTupleExpr expr, BindingSet bindings)	Check if the repository can return results for the given ExclusiveTupleExpr, e.g.
boolean	hasStatements(Resource subj, IRI pred, Value obj, QueryInfo queryInfo, Resource... contexts)	Check if the repository can return results for the given triple pattern represented by subj, pred and obj
boolean	hasStatements(StatementPattern stmt, BindingSet bindings, QueryInfo queryInfo, Dataset dataset)	Check if the provided statement can return results.
String	toString()
boolean	usePreparedQuery(StatementPattern stmt, QueryInfo queryInfo)

Methods inherited from class org.eclipse.rdf4j.federated.evaluation.TripleSourceBase

applyMaxExecutionTimeUpperBound, configureInference, getStatements, getStatements, monitorRemoteRequest, withConnection

Methods inherited from class java.lang.Object

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

Method Details

getStatements

public CloseableIteration<BindingSet> getStatements(StatementPattern stmt,
 BindingSet bindings,
 FilterValueExpr filterExpr,
 QueryInfo queryInfo)
                                             throws RepositoryException,
MalformedQueryException,
QueryEvaluationException

Description copied from interface: TripleSource

Evaluate the query expression on the provided endpoint.

Parameters:

stmt - the stmt expression to evaluate

bindings - the bindings to use

filterExpr - the filter expression to apply or null if there is no filter or if it is evaluated already

Returns:

the resulting iteration

Throws:

RepositoryException

MalformedQueryException

QueryEvaluationException

hasStatements

public boolean hasStatements(Resource subj,
 IRI pred,
 Value obj,
 QueryInfo queryInfo,
 Resource... contexts)
                      throws RepositoryException

Description copied from interface: TripleSource

Check if the repository can return results for the given triple pattern represented by subj, pred and obj

Specified by:

hasStatements in interface TripleSource

Overrides:

hasStatements in class TripleSourceBase

Parameters:

subj -

pred -

obj -

queryInfo -

contexts -

Returns:

whether the source can provide results

Throws:

RepositoryException

hasStatements

public boolean hasStatements(StatementPattern stmt,
 BindingSet bindings,
 QueryInfo queryInfo,
 Dataset dataset)
                      throws RepositoryException,
MalformedQueryException,
QueryEvaluationException

Description copied from interface: TripleSource

Check if the provided statement can return results.

Parameters:

stmt -

bindings - a binding set. in case no bindings are present, an EmptyBindingSet can be used (i.e. never null)

queryInfo -

dataset -

Returns:

whether the source can return results

Throws:

RepositoryException

MalformedQueryException

QueryEvaluationException

hasStatements

public boolean hasStatements(ExclusiveTupleExpr expr,
 BindingSet bindings)
                      throws RepositoryException,
MalformedQueryException,
QueryEvaluationException

Description copied from interface: TripleSource

Check if the repository can return results for the given ExclusiveTupleExpr, e.g. for an ExclusiveGroup with a list of Statements.

Specified by:

hasStatements in interface TripleSource

Overrides:

hasStatements in class TripleSourceBase

Parameters:

bindings -

Returns:

whether the repository can return results

Throws:

RepositoryException

MalformedQueryException

QueryEvaluationException

usePreparedQuery

public boolean usePreparedQuery(StatementPattern stmt,
 QueryInfo queryInfo)

Parameters:

stmt -

queryInfo -

Returns:

true if a prepared query is to be used preferably, false otherwise

getStatements

public CloseableIteration<BindingSet> getStatements(TupleExpr preparedQuery,
 BindingSet bindings,
 FilterValueExpr filterExpr,
 QueryInfo queryInfo)
                                             throws RepositoryException,
MalformedQueryException,
QueryEvaluationException

Description copied from interface: TripleSource

Evaluate the prepared query in its internal representation on the provided endpoint.

Parameters:

preparedQuery - a prepared query to evaluate

bindings - the bindings to use

filterExpr - the filter expression to apply or null if there is no filter or if it is evaluated already

Returns:

the resulting iteration

Throws:

RepositoryException

MalformedQueryException

QueryEvaluationException

getStatements

public CloseableIteration<Statement> getStatements(Resource subj,
 IRI pred,
 Value obj,
 QueryInfo queryInfo,
 Resource... contexts)
                                            throws RepositoryException,
MalformedQueryException,
QueryEvaluationException

Description copied from interface: TripleSource

Return the statements matching the given pattern as a Statement iteration.

Parameters:

subj -

pred -

obj -

contexts -

Returns:

the resulting iteration

Throws:

RepositoryException

MalformedQueryException

QueryEvaluationException

toString

public String toString()

Overrides:

toString in class Object