Package org.eclipse.rdf4j.federated.algebra

Class NJoin

java.lang.Object

org.eclipse.rdf4j.query.algebra.AbstractQueryModelNode

org.eclipse.rdf4j.federated.algebra.NTuple

org.eclipse.rdf4j.federated.algebra.NJoin

All Implemented Interfaces:

Serializable, Cloneable, QueryRef, QueryModelNode, TupleExpr, VariableScopeChange

public class NJoin
extends NTuple

A tuple expression that represents an nary-Join.

Author:

Andreas Schwarte

See Also:

• Serialized Form

Field Summary

Fields inherited from class org.eclipse.rdf4j.federated.algebra.NTuple

args, queryInfo

Constructor Summary

Constructors

Constructor	Description
NJoin(List<TupleExpr> args, QueryInfo queryInfo)	Construct an nary-tuple.

Method Summary

Modifier and Type	Method	Description
NJoin	clone()	Returns a (deep) clone of this query model node.
Set<String>	getJoinVariables(int joinIndex)	Returns the commons variables of the join with the given index.
<X extends Exception> void	visit(QueryModelVisitor<X> visitor)	Visits this node.

Methods inherited from class org.eclipse.rdf4j.federated.algebra.NTuple

getArg, getArgs, getAssuredBindingNames, getBindingNames, getNumberOfArguments, getOrder, getQueryInfo, getSupportedOrders, replaceChildNode, setOrder, visitChildren

Methods inherited from class org.eclipse.rdf4j.query.algebra.AbstractQueryModelNode

getCardinality, getCostEstimate, getParentNode, getResultSizeActual, getResultSizeEstimate, getSignature, getTotalTimeNanosActual, isCardinalitySet, isVariableScopeChange, nullEquals, replaceNodeInList, replaceWith, resetCardinality, setCardinality, setCostEstimate, setParentNode, setResultSizeActual, setResultSizeEstimate, setTotalTimeNanosActual, setVariableScopeChange, shouldCacheCardinality, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.eclipse.rdf4j.query.algebra.QueryModelNode

equals, getCostEstimate, getParentNode, getResultSizeActual, getResultSizeEstimate, getSignature, getTotalTimeNanosActual, replaceWith, setCostEstimate, setParentNode, setResultSizeActual, setResultSizeEstimate, setTotalTimeNanosActual, toString

Constructor Details

NJoin

public NJoin(List<TupleExpr> args,
 QueryInfo queryInfo)

Construct an nary-tuple. Note that the parentNode of all arguments is set to this instance.

Parameters:

args -

Method Details

visit

public <X extends Exception> void visit(QueryModelVisitor<X> visitor)
                                 throws X

Description copied from interface: QueryModelNode

Visits this node. The node reports itself to the visitor with the proper runtime type.

Specified by:

visit in interface QueryModelNode

Overrides:

visit in class NTuple

Throws:

X

clone

public NJoin clone()

Description copied from interface: QueryModelNode

Returns a (deep) clone of this query model node. This method recursively clones the entire node tree, starting from this nodes.

Specified by:

clone in interface QueryModelNode

Specified by:

clone in interface TupleExpr

Overrides:

clone in class NTuple

Returns:

A deep clone of this query model node.

getJoinVariables

public Set<String> getJoinVariables(int joinIndex)

Returns the commons variables of the join with the given index.

Parameters:

joinIndex - the join index, starting with 1

Returns:

the set of join variables