net.sf.saxon.expr.flwor

Class OrderByClausePush

java.lang.Object

net.sf.saxon.expr.flwor.TuplePush

net.sf.saxon.expr.flwor.OrderByClausePush

All Implemented Interfaces:

Sortable

public class OrderByClausePush
extends TuplePush
implements Sortable

Represents the tuple stream delivered by an "order by" clause. This sorts the tuple stream supplied as its input, and outputs the same tuples but in sorted order.

Field Summary

Fields

Modifier and Type	Field and Description
protected AtomicComparer[]	comparers

Constructor Summary

Constructors

Constructor and Description
OrderByClausePush(TuplePush destination, TupleExpression tupleExpr, OrderByClause orderBy, XPathContext context)

Method Summary

Modifier and Type	Method and Description
void	close() Close the tuple stream, indicating that no more tuples will be delivered
int	compare(int a, int b) Compare two objects within this Sortable, identified by their position.
void	processTuple(XPathContext context) Process the next tuple.
void	swap(int a, int b) Swap two objects within this Sortable, identified by their position.

Methods inherited from class java.lang.Object

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

Field Detail

comparers

protected AtomicComparer[] comparers

Constructor Detail

OrderByClausePush

public OrderByClausePush(TuplePush destination,
                         TupleExpression tupleExpr,
                         OrderByClause orderBy,
                         XPathContext context)

Method Detail

processTuple

public void processTuple(XPathContext context)
                  throws XPathException

Process the next tuple.

Specified by:

processTuple in class TuplePush

Parameters:

context - the dynamic evaluation context

Throws:

XPathException - if a dynamic error occurs

compare

public int compare(int a,
                   int b)

Compare two objects within this Sortable, identified by their position.

Specified by:

compare in interface Sortable

Returns:

<0 if obj[a]<obj[b], 0 if obj[a]=obj[b], >0 if obj[a]>obj[b]

swap

public void swap(int a,
                 int b)

Swap two objects within this Sortable, identified by their position.

Specified by:

swap in interface Sortable

close

public void close()
           throws XPathException

Close the tuple stream, indicating that no more tuples will be delivered

Overrides:

close in class TuplePush

Throws:

XPathException - if a dynamic error occurs