org.openrdf.query.algebra
Class Slice

java.lang.Object
  org.openrdf.query.algebra.QueryModelNodeBase
      org.openrdf.query.algebra.UnaryTupleOperator
          org.openrdf.query.algebra.Slice

All Implemented Interfaces:

Cloneable, QueryModelNode, TupleExpr

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 onan offset and limit value (both optional).

Author:

Arjohn Kampman

Field Summary

Fields inherited from class org.openrdf.query.algebra.UnaryTupleOperator

arg

Constructor Summary

Slice()

Slice(TupleExpr arg)

Slice(TupleExpr arg, int offset, int limit)

Method Summary

Slice	clone() Returns a (deep) clone of this query model node.
int	getLimit()
int	getOffset()
String	getSignature() Default implementation of QueryModelNode.getSignature() that prints the name of the node's class.
boolean	hasLimit() Checks whether the row selection has a (valid) limit.
boolean	hasOffset() Checks whether the row selection has a (valid) offset.
void	setLimit(int limit)
void	setOffset(int offset)
<X extends Exception> void	visit(QueryModelVisitor<X> visitor) Visits this node.

Methods inherited from class org.openrdf.query.algebra.UnaryTupleOperator

getArg, getBindingNames, replaceChildNode, setArg, visitChildren

Methods inherited from class org.openrdf.query.algebra.QueryModelNodeBase

getParentNode, replaceWith, setParentNode, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.openrdf.query.algebra.QueryModelNode

getParentNode, replaceWith, setParentNode, toString

Constructor Detail

Slice

public Slice()

Slice

public Slice(TupleExpr arg)

Slice

public Slice(TupleExpr arg,
             int offset,
             int limit)

Method Detail

getOffset

public int getOffset()

setOffset

public void setOffset(int offset)

hasOffset

public boolean hasOffset()

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

Returns:

true when offset > 0

getLimit

public int getLimit()

setLimit

public void setLimit(int 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 extends Exception

Description copied from interface: QueryModelNode

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

Throws:

X extends Exception

getSignature

public String getSignature()

Description copied from class: QueryModelNodeBase

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

Specified by:

getSignature in interface QueryModelNode

Overrides:

getSignature in class QueryModelNodeBase

Returns:

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

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.