Package org.eclipse.rdf4j.query.algebra

Class Slice

java.lang.Object

org.eclipse.rdf4j.query.algebra.AbstractQueryModelNode

org.eclipse.rdf4j.query.algebra.UnaryTupleOperator

org.eclipse.rdf4j.query.algebra.Slice

All Implemented Interfaces:

Serializable, Cloneable, GraphPatternGroupable, QueryModelNode, TupleExpr, VariableScopeChange

public class Slice
extends UnaryTupleOperator

The SLICE operator, as defined in SPARQL Query Language for RDF. The SLICE operator selects specific results from the underlying tuple expression based on an offset and limit value (both optional).

Author:

Arjohn Kampman

See Also:

• Serialized Form

Field Summary

Fields inherited from class org.eclipse.rdf4j.query.algebra.UnaryTupleOperator

arg

Constructor Summary

Constructors

Constructor	Description
Slice()
Slice(TupleExpr arg)
Slice(TupleExpr arg, long offset2, long limit2)

Method Summary

Modifier and Type	Method	Description
Slice	clone()	Returns a (deep) clone of this query model node.
boolean	equals(Object other)	Returns true if this query model node and its children are recursively equal to o and its children.
long	getLimit()
long	getOffset()
String	getSignature()	Default implementation of QueryModelNode.getSignature() that prints the name of the node's class.
int	hashCode()
boolean	hasLimit()	Checks whether the row selection has a (valid) limit.
boolean	hasOffset()	Checks whether the row selection has a (valid) offset.
void	setLimit(long limit)
void	setOffset(long offset)
<X extends Exception> void	visit(QueryModelVisitor<X> visitor)	Visits this node.

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

getArg, getAssuredBindingNames, getBindingNames, replaceChildNode, setArg, visitChildren

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

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

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

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

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

Constructor Details

Slice

public Slice()

Slice

public Slice(TupleExpr arg)

Slice

public Slice(TupleExpr arg,
 long offset2,
 long limit2)

Method Details

getOffset

public long getOffset()

setOffset

public void setOffset(long offset)

hasOffset

public boolean hasOffset()

Checks whether the row selection has a (valid) offset.

Returns:

true when offset > 0

getLimit

public long getLimit()

setLimit

public void setLimit(long limit)

hasLimit

public boolean hasLimit()

Checks whether the row selection has a (valid) limit.

Returns:

true when offset >= 0

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.

Throws:

X

getSignature

public String getSignature()

Description copied from class: AbstractQueryModelNode

Default implementation of QueryModelNode.getSignature() that prints the name of the node's class.

Specified by:

getSignature in interface QueryModelNode

Overrides:

getSignature in class AbstractQueryModelNode

Returns:

The node's signature, e.g. SLICE (offset=10, limit=10).

equals

public boolean equals(Object other)

Description copied from interface: QueryModelNode

Returns true if this query model node and its children are recursively equal to o and its children.

Specified by:

equals in interface QueryModelNode

Overrides:

equals in class UnaryTupleOperator

hashCode

public int hashCode()

Overrides:

hashCode in class UnaryTupleOperator

clone

public Slice 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 UnaryTupleOperator

Returns:

A deep clone of this query model node.