org.openrdf.query.algebra.evaluation.impl

Class EvaluationStrategyImpl

java.lang.Object

org.openrdf.query.algebra.evaluation.impl.EvaluationStrategyImpl

All Implemented Interfaces:

EvaluationStrategy

Direct Known Subclasses:

FederationStrategy, LimitedSizeEvaluationStrategy, RdbmsEvaluation

public class EvaluationStrategyImpl
extends Object
implements EvaluationStrategy

Evaluates the TupleExpr and ValueExpr using Iterators and common tripleSource API.

Author:

James Leigh, Arjohn Kampman, David Huynh, Andreas Schwarte

Field Summary

Fields

Modifier and Type	Field and Description
protected Dataset	dataset
protected TripleSource	tripleSource

Constructor Summary

Constructors

Constructor and Description
EvaluationStrategyImpl(TripleSource tripleSource)
EvaluationStrategyImpl(TripleSource tripleSource, Dataset dataset)

Method Summary

Modifier and Type	Method and Description
Value	evaluate(And node, BindingSet bindings)
CloseableIteration<BindingSet,QueryEvaluationException>	evaluate(ArbitraryLengthPath alp, BindingSet bindings)
CloseableIteration<BindingSet,QueryEvaluationException>	evaluate(BinaryTupleOperator expr, BindingSet bindings)
CloseableIteration<BindingSet,QueryEvaluationException>	evaluate(BindingSetAssignment bsa, BindingSet bindings)
Value	evaluate(BNodeGenerator node, BindingSet bindings)
Value	evaluate(Bound node, BindingSet bindings)
Value	evaluate(Coalesce node, BindingSet bindings)
Value	evaluate(CompareAll node, BindingSet bindings)
Value	evaluate(CompareAny node, BindingSet bindings)
Value	evaluate(Compare node, BindingSet bindings)
Value	evaluate(Datatype node, BindingSet bindings)
CloseableIteration<BindingSet,QueryEvaluationException>	evaluate(DescribeOperator operator, BindingSet bindings)
CloseableIteration<BindingSet,QueryEvaluationException>	evaluate(Difference difference, BindingSet bindings)
CloseableIteration<BindingSet,QueryEvaluationException>	evaluate(Distinct distinct, BindingSet bindings)
CloseableIteration<BindingSet,QueryEvaluationException>	evaluate(EmptySet emptySet, BindingSet bindings)
Value	evaluate(Exists node, BindingSet bindings)
CloseableIteration<BindingSet,QueryEvaluationException>	evaluate(Extension extension, BindingSet bindings)
CloseableIteration<BindingSet,QueryEvaluationException>	evaluate(ExternalSet external, BindingSet bindings)
CloseableIteration<BindingSet,QueryEvaluationException>	evaluate(Filter filter, BindingSet bindings)
Value	evaluate(FunctionCall node, BindingSet bindings) Evaluates a function.
CloseableIteration<BindingSet,QueryEvaluationException>	evaluate(Group node, BindingSet bindings)
Value	evaluate(If node, BindingSet bindings)
Value	evaluate(In node, BindingSet bindings)
CloseableIteration<BindingSet,QueryEvaluationException>	evaluate(Intersection intersection, BindingSet bindings)
URI	evaluate(IRIFunction node, BindingSet bindings) Creates a URI from the operand value (a plain literal or a URI).
Value	evaluate(IsBNode node, BindingSet bindings) Determines whether the operand (a variable) contains a BNode.
Value	evaluate(IsLiteral node, BindingSet bindings) Determines whether the operand (a variable) contains a Literal.
Value	evaluate(IsNumeric node, BindingSet bindings) Determines whether the operand (a variable) contains a numeric datatyped literal, i.e.
Value	evaluate(IsResource node, BindingSet bindings) Determines whether the operand (a variable) contains a Resource.
Value	evaluate(IsURI node, BindingSet bindings) Determines whether the operand (a variable) contains a URI.
CloseableIteration<BindingSet,QueryEvaluationException>	evaluate(Join join, BindingSet bindings)
Value	evaluate(Label node, BindingSet bindings)
Value	evaluate(Lang node, BindingSet bindings)
Value	evaluate(LangMatches node, BindingSet bindings)
CloseableIteration<BindingSet,QueryEvaluationException>	evaluate(LeftJoin leftJoin, BindingSet bindings)
Value	evaluate(Like node, BindingSet bindings) Determines whether the two operands match according to the like operator.
Value	evaluate(ListMemberOperator node, BindingSet bindings)
Value	evaluate(LocalName node, BindingSet bindings)
Value	evaluate(MathExpr node, BindingSet bindings)
CloseableIteration<BindingSet,QueryEvaluationException>	evaluate(MultiProjection multiProjection, BindingSet bindings)
Value	evaluate(Namespace node, BindingSet bindings)
Value	evaluate(Not node, BindingSet bindings)
Value	evaluate(Or node, BindingSet bindings)
CloseableIteration<BindingSet,QueryEvaluationException>	evaluate(Order node, BindingSet bindings)
CloseableIteration<BindingSet,QueryEvaluationException>	evaluate(Projection projection, BindingSet bindings)
CloseableIteration<BindingSet,QueryEvaluationException>	evaluate(Reduced reduced, BindingSet bindings)
Value	evaluate(Regex node, BindingSet bindings) Determines whether the two operands match according to the regex operator.
Value	evaluate(SameTerm node, BindingSet bindings)
CloseableIteration<BindingSet,QueryEvaluationException>	evaluate(Service service, BindingSet bindings)
CloseableIteration<BindingSet,QueryEvaluationException>	evaluate(SingletonSet singletonSet, BindingSet bindings)
CloseableIteration<BindingSet,QueryEvaluationException>	evaluate(Slice slice, BindingSet bindings)
CloseableIteration<BindingSet,QueryEvaluationException>	evaluate(StatementPattern sp, BindingSet bindings)
Value	evaluate(Str node, BindingSet bindings)
CloseableIteration<BindingSet,QueryEvaluationException>	evaluate(TupleExpr expr, BindingSet bindings) Evaluates the tuple expression against the supplied triple source with the specified set of variable bindings as input.
CloseableIteration<BindingSet,QueryEvaluationException>	evaluate(UnaryTupleOperator expr, BindingSet bindings)
CloseableIteration<BindingSet,QueryEvaluationException>	evaluate(Union union, BindingSet bindings)
Value	evaluate(ValueConstant valueConstant, BindingSet bindings)
Value	evaluate(ValueExpr expr, BindingSet bindings) Gets the value of this expression.
Value	evaluate(Var var, BindingSet bindings)
CloseableIteration<BindingSet,QueryEvaluationException>	evaluate(ZeroLengthPath zlp, BindingSet bindings)
protected long	getLimit(QueryModelNode node) Returns the limit of the current variable bindings before any further projection.
protected Value	getVarValue(Var var, BindingSet bindings)
protected ZeroLengthPathIteration	getZeroLengthPathIterator(BindingSet bindings, Var subjectVar, Var objVar, Var contextVar, Value subj, Value obj)
protected boolean	isReducedOrDistinct(QueryModelNode node)
boolean	isTrue(ValueExpr expr, BindingSet bindings) Evaluates the boolean expression on the supplied TripleSource object.

Methods inherited from class java.lang.Object

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

Field Detail

tripleSource

protected final TripleSource tripleSource

dataset

protected final Dataset dataset

Constructor Detail

EvaluationStrategyImpl

public EvaluationStrategyImpl(TripleSource tripleSource)

EvaluationStrategyImpl

public EvaluationStrategyImpl(TripleSource tripleSource,
                              Dataset dataset)

Method Detail

evaluate

public CloseableIteration<BindingSet,QueryEvaluationException> evaluate(TupleExpr expr,
                                                                        BindingSet bindings)
                                                                 throws QueryEvaluationException

Description copied from interface: EvaluationStrategy

Evaluates the tuple expression against the supplied triple source with the specified set of variable bindings as input.

Specified by:

evaluate in interface EvaluationStrategy

Parameters:

expr - The Tuple Expression to evaluate

bindings - The variables bindings to use for evaluating the expression, if applicable.

Returns:

A closeable iterator over the variable binding sets that match the tuple expression.

Throws:

QueryEvaluationException

evaluate

public CloseableIteration<BindingSet,QueryEvaluationException> evaluate(ArbitraryLengthPath alp,
                                                                        BindingSet bindings)
                                                                 throws QueryEvaluationException

Throws:

QueryEvaluationException

evaluate

public CloseableIteration<BindingSet,QueryEvaluationException> evaluate(ZeroLengthPath zlp,
                                                                        BindingSet bindings)
                                                                 throws QueryEvaluationException

Throws:

QueryEvaluationException

getZeroLengthPathIterator

protected ZeroLengthPathIteration getZeroLengthPathIterator(BindingSet bindings,
                                                            Var subjectVar,
                                                            Var objVar,
                                                            Var contextVar,
                                                            Value subj,
                                                            Value obj)

evaluate

public CloseableIteration<BindingSet,QueryEvaluationException> evaluate(Service service,
                                                                        BindingSet bindings)
                                                                 throws QueryEvaluationException

Throws:

QueryEvaluationException

evaluate

public CloseableIteration<BindingSet,QueryEvaluationException> evaluate(DescribeOperator operator,
                                                                        BindingSet bindings)
                                                                 throws QueryEvaluationException

Throws:

QueryEvaluationException

evaluate

public CloseableIteration<BindingSet,QueryEvaluationException> evaluate(StatementPattern sp,
                                                                        BindingSet bindings)
                                                                 throws QueryEvaluationException

Throws:

QueryEvaluationException

getVarValue

protected Value getVarValue(Var var,
                            BindingSet bindings)

evaluate

public CloseableIteration<BindingSet,QueryEvaluationException> evaluate(UnaryTupleOperator expr,
                                                                        BindingSet bindings)
                                                                 throws QueryEvaluationException

Throws:

QueryEvaluationException

evaluate

public CloseableIteration<BindingSet,QueryEvaluationException> evaluate(BindingSetAssignment bsa,
                                                                        BindingSet bindings)
                                                                 throws QueryEvaluationException

Throws:

QueryEvaluationException

evaluate

public CloseableIteration<BindingSet,QueryEvaluationException> evaluate(Projection projection,
                                                                        BindingSet bindings)
                                                                 throws QueryEvaluationException

Throws:

QueryEvaluationException

evaluate

public CloseableIteration<BindingSet,QueryEvaluationException> evaluate(MultiProjection multiProjection,
                                                                        BindingSet bindings)
                                                                 throws QueryEvaluationException

Throws:

QueryEvaluationException

evaluate

public CloseableIteration<BindingSet,QueryEvaluationException> evaluate(Filter filter,
                                                                        BindingSet bindings)
                                                                 throws QueryEvaluationException

Throws:

QueryEvaluationException

evaluate

public CloseableIteration<BindingSet,QueryEvaluationException> evaluate(Slice slice,
                                                                        BindingSet bindings)
                                                                 throws QueryEvaluationException

Throws:

QueryEvaluationException

evaluate

public CloseableIteration<BindingSet,QueryEvaluationException> evaluate(Extension extension,
                                                                        BindingSet bindings)
                                                                 throws QueryEvaluationException

Throws:

QueryEvaluationException

evaluate

public CloseableIteration<BindingSet,QueryEvaluationException> evaluate(Distinct distinct,
                                                                        BindingSet bindings)
                                                                 throws QueryEvaluationException

Throws:

QueryEvaluationException

evaluate

public CloseableIteration<BindingSet,QueryEvaluationException> evaluate(Reduced reduced,
                                                                        BindingSet bindings)
                                                                 throws QueryEvaluationException

Throws:

QueryEvaluationException

evaluate

public CloseableIteration<BindingSet,QueryEvaluationException> evaluate(Group node,
                                                                        BindingSet bindings)
                                                                 throws QueryEvaluationException

Throws:

QueryEvaluationException

evaluate

public CloseableIteration<BindingSet,QueryEvaluationException> evaluate(Order node,
                                                                        BindingSet bindings)
                                                                 throws QueryEvaluationException

Throws:

QueryEvaluationException

evaluate

public CloseableIteration<BindingSet,QueryEvaluationException> evaluate(BinaryTupleOperator expr,
                                                                        BindingSet bindings)
                                                                 throws QueryEvaluationException

Throws:

QueryEvaluationException

evaluate

public CloseableIteration<BindingSet,QueryEvaluationException> evaluate(Join join,
                                                                        BindingSet bindings)
                                                                 throws QueryEvaluationException

Throws:

QueryEvaluationException

evaluate

public CloseableIteration<BindingSet,QueryEvaluationException> evaluate(LeftJoin leftJoin,
                                                                        BindingSet bindings)
                                                                 throws QueryEvaluationException

Throws:

QueryEvaluationException

evaluate

public CloseableIteration<BindingSet,QueryEvaluationException> evaluate(Union union,
                                                                        BindingSet bindings)
                                                                 throws QueryEvaluationException

Throws:

QueryEvaluationException

evaluate

public CloseableIteration<BindingSet,QueryEvaluationException> evaluate(Intersection intersection,
                                                                        BindingSet bindings)
                                                                 throws QueryEvaluationException

Throws:

QueryEvaluationException

evaluate

public CloseableIteration<BindingSet,QueryEvaluationException> evaluate(Difference difference,
                                                                        BindingSet bindings)
                                                                 throws QueryEvaluationException

Throws:

QueryEvaluationException

evaluate

public CloseableIteration<BindingSet,QueryEvaluationException> evaluate(SingletonSet singletonSet,
                                                                        BindingSet bindings)
                                                                 throws QueryEvaluationException

Throws:

QueryEvaluationException

evaluate

public CloseableIteration<BindingSet,QueryEvaluationException> evaluate(EmptySet emptySet,
                                                                        BindingSet bindings)
                                                                 throws QueryEvaluationException

Throws:

QueryEvaluationException

evaluate

public CloseableIteration<BindingSet,QueryEvaluationException> evaluate(ExternalSet external,
                                                                        BindingSet bindings)
                                                                 throws QueryEvaluationException

Throws:

QueryEvaluationException

evaluate

public Value evaluate(ValueExpr expr,
                      BindingSet bindings)
               throws ValueExprEvaluationException,
                      QueryEvaluationException

Description copied from interface: EvaluationStrategy

Gets the value of this expression.

Specified by:

evaluate in interface EvaluationStrategy

bindings - The variables bindings to use for evaluating the expression, if applicable.

Returns:

The Value that this expression evaluates to, or null if the expression could not be evaluated.

Throws:

ValueExprEvaluationException

QueryEvaluationException

evaluate

public Value evaluate(Var var,
                      BindingSet bindings)
               throws ValueExprEvaluationException,
                      QueryEvaluationException

Throws:

ValueExprEvaluationException

QueryEvaluationException

evaluate

public Value evaluate(ValueConstant valueConstant,
                      BindingSet bindings)
               throws ValueExprEvaluationException,
                      QueryEvaluationException

Throws:

ValueExprEvaluationException

QueryEvaluationException

evaluate

public Value evaluate(BNodeGenerator node,
                      BindingSet bindings)
               throws ValueExprEvaluationException,
                      QueryEvaluationException

Throws:

ValueExprEvaluationException

QueryEvaluationException

evaluate

public Value evaluate(Bound node,
                      BindingSet bindings)
               throws QueryEvaluationException

Throws:

QueryEvaluationException

evaluate

public Value evaluate(Str node,
                      BindingSet bindings)
               throws ValueExprEvaluationException,
                      QueryEvaluationException

Throws:

ValueExprEvaluationException

QueryEvaluationException

evaluate

public Value evaluate(Label node,
                      BindingSet bindings)
               throws ValueExprEvaluationException,
                      QueryEvaluationException

Throws:

ValueExprEvaluationException

QueryEvaluationException

evaluate

public Value evaluate(Lang node,
                      BindingSet bindings)
               throws ValueExprEvaluationException,
                      QueryEvaluationException

Throws:

ValueExprEvaluationException

QueryEvaluationException

evaluate

public Value evaluate(Datatype node,
                      BindingSet bindings)
               throws ValueExprEvaluationException,
                      QueryEvaluationException

Throws:

ValueExprEvaluationException

QueryEvaluationException

evaluate

public Value evaluate(Namespace node,
                      BindingSet bindings)
               throws ValueExprEvaluationException,
                      QueryEvaluationException

Throws:

ValueExprEvaluationException

QueryEvaluationException

evaluate

public Value evaluate(LocalName node,
                      BindingSet bindings)
               throws ValueExprEvaluationException,
                      QueryEvaluationException

Throws:

ValueExprEvaluationException

QueryEvaluationException

evaluate

public Value evaluate(IsResource node,
                      BindingSet bindings)
               throws ValueExprEvaluationException,
                      QueryEvaluationException

Determines whether the operand (a variable) contains a Resource.

Returns:

true if the operand contains a Resource, false otherwise.

Throws:

ValueExprEvaluationException

QueryEvaluationException

evaluate

public Value evaluate(IsURI node,
                      BindingSet bindings)
               throws ValueExprEvaluationException,
                      QueryEvaluationException

Determines whether the operand (a variable) contains a URI.

Returns:

true if the operand contains a URI, false otherwise.

Throws:

ValueExprEvaluationException

QueryEvaluationException

evaluate

public Value evaluate(IsBNode node,
                      BindingSet bindings)
               throws ValueExprEvaluationException,
                      QueryEvaluationException

Determines whether the operand (a variable) contains a BNode.

Returns:

true if the operand contains a BNode, false otherwise.

Throws:

ValueExprEvaluationException

QueryEvaluationException

evaluate

public Value evaluate(IsLiteral node,
                      BindingSet bindings)
               throws ValueExprEvaluationException,
                      QueryEvaluationException

Determines whether the operand (a variable) contains a Literal.

Returns:

true if the operand contains a Literal, false otherwise.

Throws:

ValueExprEvaluationException

QueryEvaluationException

evaluate

public Value evaluate(IsNumeric node,
                      BindingSet bindings)
               throws ValueExprEvaluationException,
                      QueryEvaluationException

Determines whether the operand (a variable) contains a numeric datatyped literal, i.e. a literal with datatype xsd:float, xsd:double, xsd:decimal, or a derived datatype of xsd:decimal.

Returns:

true if the operand contains a numeric datatyped literal, false otherwise.

Throws:

ValueExprEvaluationException

QueryEvaluationException

evaluate

public URI evaluate(IRIFunction node,
                    BindingSet bindings)
             throws ValueExprEvaluationException,
                    QueryEvaluationException

Creates a URI from the operand value (a plain literal or a URI).

Parameters:

node - represents an invocation of the SPARQL IRI function

bindings - used to generate the value that the URI is based on

Returns:

a URI generated from the given arguments

Throws:

ValueExprEvaluationException

QueryEvaluationException

evaluate

public Value evaluate(Regex node,
                      BindingSet bindings)
               throws ValueExprEvaluationException,
                      QueryEvaluationException

Determines whether the two operands match according to the regex operator.

Returns:

true if the operands match according to the regex operator, false otherwise.

Throws:

ValueExprEvaluationException

QueryEvaluationException

evaluate

public Value evaluate(LangMatches node,
                      BindingSet bindings)
               throws ValueExprEvaluationException,
                      QueryEvaluationException

Throws:

ValueExprEvaluationException

QueryEvaluationException

evaluate

public Value evaluate(Like node,
                      BindingSet bindings)
               throws ValueExprEvaluationException,
                      QueryEvaluationException

Determines whether the two operands match according to the like operator. The operator is defined as a string comparison with the possible use of an asterisk (*) at the end and/or the start of the second operand to indicate substring matching.

Returns:

true if the operands match according to the like operator, false otherwise.

Throws:

ValueExprEvaluationException

QueryEvaluationException

evaluate

public Value evaluate(FunctionCall node,
                      BindingSet bindings)
               throws ValueExprEvaluationException,
                      QueryEvaluationException

Evaluates a function.

Throws:

ValueExprEvaluationException

QueryEvaluationException

evaluate

public Value evaluate(And node,
                      BindingSet bindings)
               throws ValueExprEvaluationException,
                      QueryEvaluationException

Throws:

ValueExprEvaluationException

QueryEvaluationException

evaluate

public Value evaluate(Or node,
                      BindingSet bindings)
               throws ValueExprEvaluationException,
                      QueryEvaluationException

Throws:

ValueExprEvaluationException

QueryEvaluationException

evaluate

public Value evaluate(Not node,
                      BindingSet bindings)
               throws ValueExprEvaluationException,
                      QueryEvaluationException

Throws:

ValueExprEvaluationException

QueryEvaluationException

evaluate

public Value evaluate(SameTerm node,
                      BindingSet bindings)
               throws ValueExprEvaluationException,
                      QueryEvaluationException

Throws:

ValueExprEvaluationException

QueryEvaluationException

evaluate

public Value evaluate(Coalesce node,
                      BindingSet bindings)
               throws ValueExprEvaluationException

Throws:

ValueExprEvaluationException

evaluate

public Value evaluate(Compare node,
                      BindingSet bindings)
               throws ValueExprEvaluationException,
                      QueryEvaluationException

Throws:

ValueExprEvaluationException

QueryEvaluationException

evaluate

public Value evaluate(MathExpr node,
                      BindingSet bindings)
               throws ValueExprEvaluationException,
                      QueryEvaluationException

Throws:

ValueExprEvaluationException

QueryEvaluationException

evaluate

public Value evaluate(If node,
                      BindingSet bindings)
               throws QueryEvaluationException

Throws:

QueryEvaluationException

evaluate

public Value evaluate(In node,
                      BindingSet bindings)
               throws ValueExprEvaluationException,
                      QueryEvaluationException

Throws:

ValueExprEvaluationException

QueryEvaluationException

evaluate

public Value evaluate(ListMemberOperator node,
                      BindingSet bindings)
               throws ValueExprEvaluationException,
                      QueryEvaluationException

Throws:

ValueExprEvaluationException

QueryEvaluationException

evaluate

public Value evaluate(CompareAny node,
                      BindingSet bindings)
               throws ValueExprEvaluationException,
                      QueryEvaluationException

Throws:

ValueExprEvaluationException

QueryEvaluationException

evaluate

public Value evaluate(CompareAll node,
                      BindingSet bindings)
               throws ValueExprEvaluationException,
                      QueryEvaluationException

Throws:

ValueExprEvaluationException

QueryEvaluationException

evaluate

public Value evaluate(Exists node,
                      BindingSet bindings)
               throws ValueExprEvaluationException,
                      QueryEvaluationException

Throws:

ValueExprEvaluationException

QueryEvaluationException

isTrue

public boolean isTrue(ValueExpr expr,
                      BindingSet bindings)
               throws QueryEvaluationException

Description copied from interface: EvaluationStrategy

Evaluates the boolean expression on the supplied TripleSource object.

Specified by:

isTrue in interface EvaluationStrategy

bindings - The variables bindings to use for evaluating the expression, if applicable.

Returns:

The result of the evaluation.

Throws:

ValueExprEvaluationException - If the value expression could not be evaluated, for example when comparing two incompatible operands. When thrown, the result of the boolean expression is neither true nor false, but unknown.

QueryEvaluationException

isReducedOrDistinct

protected boolean isReducedOrDistinct(QueryModelNode node)

getLimit

protected long getLimit(QueryModelNode node)

Returns the limit of the current variable bindings before any further projection.