Package com.complexible.stardog.plan.eval.service

Interface Service

public interface Service

Interface representing a Service that is capable of providing results due to the evaluation of a SPARQL query.

Since:
3.0
Author:
Michael Grove

  • Method Summary

    Modifier and Type
    Method
    Description
    default boolean
    answersSparqlQueries()
    Are queries against this service SPARQL queries? If so, we can perform reasoning, etc.
    boolean
    canEvaluate(IRI iri)
    Return whether or not the Service can answer
    default boolean
    customTermReplacement()
    If this returns true, the service is expected to override replaceQueryTerms(PlanNodeVarReplacer, ServicePlanNode) to implement custom logic of replacing query terms.
    default BooleanSupplier
    getAvailability(IRI serviceIri)
    Return a BooleanSupplier that indicates whether the service is available (not closed) and therefore still valid for use in the cache The purpose of using a BooleanSupplier rather than just calling an availability method is to account for the possibility that a Service may delegate to different virtual graphs over time.
    default boolean
    isAccessibleFrom(String database, IRI serviceIri)
     
    default com.complexible.stardog.plan.PlanNode
    replaceQueryTerms(com.complexible.stardog.plan.util.PlanNodeVarReplacer replacer, com.complexible.stardog.plan.ServicePlanNode serviceNode)
    Replaces query terms in the given ServicePlanNode.
    default boolean
    respectsNamedGraphSecurity()
    Is the service restricted to graphs accessible according to the named graph security constraints?
    default boolean
    supportsConstantReplacement()
    Does this service create queries which support constant replacement? If so, caching with constant canonicalization is performed.
    default com.complexible.stardog.plan.PlanNode
    translate(com.complexible.stardog.plan.eval.ExecutionContext theExecutionContext, IRI iri, com.complexible.stardog.plan.PlanNode body, com.complexible.stardog.plan.QueryTerm context, IntFunction<String> varNames, Function<String,Integer> varAllocator, boolean silent)
     
    com.complexible.stardog.plan.PlanNode
    translate(com.complexible.stardog.plan.eval.ExecutionContext theExecutionContext, IRI iri, com.complexible.stardog.plan.PlanNode body, IntFunction<String> varNames, Function<String,Integer> varAllocator, boolean silent)
    Translate a query fragment to a call to this service
    default com.complexible.stardog.plan.PlanNode
    translate(com.complexible.stardog.plan.optimizer.OptimizationContext theOptimizationContext, IRI iri, com.complexible.stardog.plan.PlanNode body, com.complexible.stardog.plan.QueryTerm context, IntFunction<String> varNames, Function<String,Integer> varAllocator, boolean silent)
     
    default com.complexible.stardog.plan.PlanNode
    translate(com.complexible.stardog.plan.optimizer.OptimizationContext theOptimizationContext, IRI iri, com.complexible.stardog.plan.PlanNode body, IntFunction<String> varNames, Function<String,Integer> varAllocator, boolean silent)
    Translate a query fragment to a call to this service.

  • Method Details

    • canEvaluate

      boolean canEvaluate(IRI iri)
      Return whether or not the Service can answer
      Parameters:
      iri - the IRI of the service
      Returns:
      true if this service can evaluate the query, false otherwise

    • translate

      com.complexible.stardog.plan.PlanNode translate(com.complexible.stardog.plan.eval.ExecutionContext theExecutionContext, IRI iri, com.complexible.stardog.plan.PlanNode body, IntFunction<String> varNames, Function<String,Integer> varAllocator, boolean silent)
      Translate a query fragment to a call to this service

    • translate

      default com.complexible.stardog.plan.PlanNode translate(com.complexible.stardog.plan.eval.ExecutionContext theExecutionContext, IRI iri, com.complexible.stardog.plan.PlanNode body, com.complexible.stardog.plan.QueryTerm context, IntFunction<String> varNames, Function<String,Integer> varAllocator, boolean silent)

    • translate

      default com.complexible.stardog.plan.PlanNode translate(com.complexible.stardog.plan.optimizer.OptimizationContext theOptimizationContext, IRI iri, com.complexible.stardog.plan.PlanNode body, IntFunction<String> varNames, Function<String,Integer> varAllocator, boolean silent)
      Translate a query fragment to a call to this service. We may also pass the Optimization context here. This allows for applying optimizations after translation (see e.g., VirtualGraphService)

    • translate

      default com.complexible.stardog.plan.PlanNode translate(com.complexible.stardog.plan.optimizer.OptimizationContext theOptimizationContext, IRI iri, com.complexible.stardog.plan.PlanNode body, com.complexible.stardog.plan.QueryTerm context, IntFunction<String> varNames, Function<String,Integer> varAllocator, boolean silent)

    • respectsNamedGraphSecurity

      default boolean respectsNamedGraphSecurity()
      Is the service restricted to graphs accessible according to the named graph security constraints?

    • supportsConstantReplacement

      default boolean supportsConstantReplacement()
      Does this service create queries which support constant replacement? If so, caching with constant canonicalization is performed. If not, the service body will be added to the cache without canonicalization.

    • customTermReplacement

      default boolean customTermReplacement()
      If this returns true, the service is expected to override replaceQueryTerms(PlanNodeVarReplacer, ServicePlanNode) to implement custom logic of replacing query terms.

    • replaceQueryTerms

      default com.complexible.stardog.plan.PlanNode replaceQueryTerms(com.complexible.stardog.plan.util.PlanNodeVarReplacer replacer, com.complexible.stardog.plan.ServicePlanNode serviceNode)
      Replaces query terms in the given ServicePlanNode. Most services would simply delegate to the PlanNodeVarReplacer but some may require custom logic for inlining constants etc.

    • answersSparqlQueries

      default boolean answersSparqlQueries()
      Are queries against this service SPARQL queries? If so, we can perform reasoning, etc.

    • getAvailability

      default BooleanSupplier getAvailability(IRI serviceIri)
      Return a BooleanSupplier that indicates whether the service is available (not closed) and therefore still valid for use in the cache The purpose of using a BooleanSupplier rather than just calling an availability method is to account for the possibility that a Service may delegate to different virtual graphs over time. The BooleanSupplier will return the availability of the virtual graph that handled this serviceIri at the time this method is called, not when BooleanSupplier.getAsBoolean() is called. Important for plan cache invalidation.

    • isAccessibleFrom

      default boolean isAccessibleFrom(String database, IRI serviceIri)