org.eclipse.rdf4j.query.parser.sparql

Class GraphPattern

java.lang.Object

org.eclipse.rdf4j.query.parser.sparql.GraphPattern

public class GraphPattern
extends Object

A graph pattern consisting of (required and optional) tuple expressions, binding assignments and boolean constraints.

Author:

Arjohn Kampman

Constructor Summary

Constructors

Constructor and Description
GraphPattern() Creates a new graph pattern.
GraphPattern(GraphPattern parent) Creates a new graph pattern that inherits the context and scope from a parent graph pattern.

Method Summary

Modifier and Type	Method and Description
void	addConstraint(ValueExpr constraint)
void	addConstraints(Collection<ValueExpr> constraints)
void	addOptionalTE(TupleExpr te, List<ValueExpr> constraints) add the supplied tuple expression as an optional expression, with a list of constraints that hold as conditions.
void	addRequiredSP(Var subjVar, Var predVar, Var objVar)
void	addRequiredTE(TupleExpr te)
TupleExpr	buildTupleExpr() Builds a combined tuple expression from the tuple expressions and constraints in this graph pattern.
void	clear() Removes all tuple expressions and constraints.
List<ValueExpr>	getConstraints()
Var	getContextVar()
List<Map.Entry<TupleExpr,List<ValueExpr>>>	getOptionalTEs() Retrieves the optional tuple expressions as a list of tuples with the tuple expression as the key and the list of value expressions as the value.
List<TupleExpr>	getRequiredTEs()
StatementPattern.Scope	getStatementPatternScope()
List<ValueExpr>	removeAllConstraints()
void	setContextVar(Var contextVar)
void	setStatementPatternScope(StatementPattern.Scope spScope)

Methods inherited from class java.lang.Object

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

Constructor Detail

GraphPattern

public GraphPattern()

Creates a new graph pattern.

GraphPattern

public GraphPattern(GraphPattern parent)

Creates a new graph pattern that inherits the context and scope from a parent graph pattern.

Method Detail

setContextVar

public void setContextVar(Var contextVar)

getContextVar

public Var getContextVar()

setStatementPatternScope

public void setStatementPatternScope(StatementPattern.Scope spScope)

getStatementPatternScope

public StatementPattern.Scope getStatementPatternScope()

addRequiredTE

public void addRequiredTE(TupleExpr te)

addRequiredSP

public void addRequiredSP(Var subjVar,
                          Var predVar,
                          Var objVar)

getRequiredTEs

public List<TupleExpr> getRequiredTEs()

addOptionalTE

public void addOptionalTE(TupleExpr te,
                          List<ValueExpr> constraints)

add the supplied tuple expression as an optional expression, with a list of constraints that hold as conditions.

Parameters:

te - a tuple expression

constraints - a list of constraints that form a condition for the LeftJoin to be formed from the optional TE.

getOptionalTEs

public List<Map.Entry<TupleExpr,List<ValueExpr>>> getOptionalTEs()

Retrieves the optional tuple expressions as a list of tuples with the tuple expression as the key and the list of value expressions as the value.

Returns:

a list of Map entries.

addConstraint

public void addConstraint(ValueExpr constraint)

addConstraints

public void addConstraints(Collection<ValueExpr> constraints)

getConstraints

public List<ValueExpr> getConstraints()

removeAllConstraints

public List<ValueExpr> removeAllConstraints()

clear

public void clear()

Removes all tuple expressions and constraints.

buildTupleExpr

public TupleExpr buildTupleExpr()

Builds a combined tuple expression from the tuple expressions and constraints in this graph pattern.

Returns:

A tuple expression for this graph pattern.