org.openrdf.query.algebra
Class Group

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

All Implemented Interfaces:

Cloneable, QueryModelNode, TupleExpr

public class Group
extends UnaryTupleOperator

A tuple operator that groups tuples that have a specific set of equivalent variable bindings, and that can apply aggregate functions on the grouped results.

Author:

David Huynh, Arjohn Kampman

Field Summary

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

arg

Constructor Summary

Group(TupleExpr arg)

Group(TupleExpr arg, Iterable<String> groupBindingNames)

Group(TupleExpr arg, Iterable<String> groupBindingNames, Iterable<GroupElem> groupElements)

Method Summary

void	addGroupBindingName(String bindingName)
void	addGroupElement(GroupElem groupElem)
Group	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.
Set<String>	getAggregateBindingNames()
Set<String>	getAssuredBindingNames() Gets the names of the bindings that are guaranteed to be present in the results produced by this tuple expression.
Set<String>	getBindingNames() Gets the names of the bindings that are, or can be, returned by this tuple expression when it is evaluated.
Set<String>	getGroupBindingNames()
List<GroupElem>	getGroupElements()
String	getSignature() Default implementation of QueryModelNode.getSignature() that prints the name of the node's class.
int	hashCode()
void	replaceChildNode(QueryModelNode current, QueryModelNode replacement) Default implementation of QueryModelNode.replaceChildNode(QueryModelNode, QueryModelNode) that throws an IllegalArgumentException indicating that current is not a child node of this node.
void	setGroupBindingNames(Iterable<String> bindingNames)
void	setGroupElements(Iterable<GroupElem> elements)
<X extends Exception> void	visit(QueryModelVisitor<X> visitor) Visits this node.
<X extends Exception> void	visitChildren(QueryModelVisitor<X> visitor) Dummy implementation of QueryModelNode.visitChildren(org.openrdf.query.algebra.QueryModelVisitor) that does nothing.

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

getArg, setArg

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

getParentNode, nullEquals, replaceNodeInList, replaceWith, setParentNode, toString

Methods inherited from class java.lang.Object

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

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

getParentNode, replaceWith, setParentNode, toString

Constructor Detail

Group

public Group(TupleExpr arg)

Group

public Group(TupleExpr arg,
             Iterable<String> groupBindingNames)

Group

public Group(TupleExpr arg,
             Iterable<String> groupBindingNames,
             Iterable<GroupElem> groupElements)

Method Detail

getGroupBindingNames

public Set<String> getGroupBindingNames()

addGroupBindingName

public void addGroupBindingName(String bindingName)

setGroupBindingNames

public void setGroupBindingNames(Iterable<String> bindingNames)

getGroupElements

public List<GroupElem> getGroupElements()

addGroupElement

public void addGroupElement(GroupElem groupElem)

setGroupElements

public void setGroupElements(Iterable<GroupElem> elements)

getAggregateBindingNames

public Set<String> getAggregateBindingNames()

getBindingNames

public Set<String> getBindingNames()

Description copied from interface: TupleExpr

Gets the names of the bindings that are, or can be, returned by this tuple expression when it is evaluated.

Specified by:

getBindingNames in interface TupleExpr

Overrides:

getBindingNames in class UnaryTupleOperator

Returns:

A set of binding names.

getAssuredBindingNames

public Set<String> getAssuredBindingNames()

Description copied from interface: TupleExpr

Gets the names of the bindings that are guaranteed to be present in the results produced by this tuple expression.

Specified by:

getAssuredBindingNames in interface TupleExpr

Overrides:

getAssuredBindingNames in class UnaryTupleOperator

Returns:

A set of binding names.

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

visitChildren

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

Description copied from class: QueryModelNodeBase

Dummy implementation of QueryModelNode.visitChildren(org.openrdf.query.algebra.QueryModelVisitor) that does nothing. Subclasses should override this method when they have child nodes.

Specified by:

visitChildren in interface QueryModelNode

Overrides:

visitChildren in class UnaryTupleOperator

Throws:

X extends Exception

replaceChildNode

public void replaceChildNode(QueryModelNode current,
                             QueryModelNode replacement)

Description copied from class: QueryModelNodeBase

Default implementation of QueryModelNode.replaceChildNode(QueryModelNode, QueryModelNode) that throws an IllegalArgumentException indicating that current is not a child node of this node.

Specified by:

replaceChildNode in interface QueryModelNode

Overrides:

replaceChildNode in class UnaryTupleOperator

Parameters:

current - The current child node.

replacement - The new child node.

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 Group 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.

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).