Class StatementPatternQueryEvaluationStep

java.lang.Object
org.eclipse.rdf4j.query.algebra.evaluation.impl.evaluationsteps.StatementPatternQueryEvaluationStep
All Implemented Interfaces:
QueryEvaluationStep

public class StatementPatternQueryEvaluationStep extends Object implements QueryEvaluationStep
Evaluate the StatementPattern - taking care of graph/datasets - avoiding redoing work every call of evaluate if possible.
  • Constructor Details

  • Method Details

    • evaluate

      Specified by:
      evaluate in interface QueryEvaluationStep
    • filterContextOrEqualVariables

      protected static Predicate<Statement> filterContextOrEqualVariables(StatementPattern statementPattern, Value subjValue, Value predValue, Value objValue, Resource[] contexts)
      Generate a predicate that tests for Named contexts are matched by retrieving all statements from the store and filtering out the statements that do not have a context. Or the same variable might have been used multiple times in this StatementPattern, verify value equality in those cases.
    • extractContextsFromDatasets

      protected static Function<Value,Resource[]> extractContextsFromDatasets(Var contextVar, boolean emptyGraph, Set<IRI> graphs)
      Parameters:
      statementPattern -
      contextValue -
      Returns:
      the contexts that are valid for this statement pattern or null