org.openanzo.glitter.expression
Interface Function

All Known Subinterfaces:

FunctionOnTerms, FunctionOnValues, FunctionOnValuesAndErrors

All Known Implementing Classes:

BinaryFunction, BooleanEq, BooleanGe, BooleanGt, BooleanLe, BooleanLt, BooleanNe, Bound, Datatype, DateTimeEq, DateTimeGe, DateTimeGt, DateTimeLe, DateTimeLt, DateTimeNe, FunctionBase, IsBlank, IsIRI, IsLiteral, Lang, LangMatches, LogicalAnd, LogicalOr, Not, NumericAdd, NumericDivide, NumericEq, NumericGe, NumericGt, NumericLe, NumericLt, NumericMultiply, NumericNe, NumericSubtract, PolymorphicEq, PolymorphicFunction, PolymorphicGe, PolymorphicGt, PolymorphicLe, PolymorphicLt, PolymorphicNe, RDFTermEq, RDFTermNe, RegEx, SameTerm, Str, StringLiteralGe, StringLiteralGt, StringLiteralLe, StringLiteralLt, UnaryFunction, UnaryMinus, UnaryPlus, XSDDouble, XSDInteger, XSDString

public interface Function

The base interface representing all SPARQL functions. SPARQL functions are identified by a URI, and either operate on evaluated values (variables bindings) or on terms (e.g. Bound). Also, while most functions return a type error if any argument is a type error, some functions may choose to operate on type error arguments.

Author:

lee

Method Summary

java.net.URI	getIdentifier()
boolean	operatesOnTypeErrors()
boolean	operatesOnValues()

Method Detail

getIdentifier

java.net.URI getIdentifier()

Returns:

The identifier for this function

operatesOnValues

boolean operatesOnValues()

Returns:

true if this function's arguments should be values evaluated in the context of the environment created from each set of bindings (solution); false if the function operates directly on the surface term (e.g. a hypothetical function isVariable would operate on terms and return false)

operatesOnTypeErrors

boolean operatesOnTypeErrors()

Returns:

true if the function can process type errors as arguments; false if the function simply propagates type errors