net.sf.saxon.expr.flwor

Class OrderByClause

java.lang.Object

net.sf.saxon.expr.flwor.Clause

net.sf.saxon.expr.flwor.OrderByClause

public class OrderByClause
extends Clause

This class represents an "order by" clause in a FLWOR expression

Field Summary

Fields

Modifier and Type	Field and Description
static OperandRole	SORT_KEYS_ROLE

Fields inherited from class net.sf.saxon.expr.flwor.Clause

COUNT, FOR, GROUPBYCLAUSE, LET, ORDERBYCLAUSE, TRACE, WHERE, WINDOW

Constructor Summary

Constructors

Constructor and Description
OrderByClause(FLWORExpression flwor, SortKeyDefinition[] sortKeys, TupleExpression tupleExpression)

Method Summary

Modifier and Type	Method and Description
void	addToPathMap(PathMap pathMap, PathMap.PathMapNodeSet pathMapNodeSet) Collect information about the navigation paths followed by this clause, for document projection purposes
boolean	containsNonInlineableVariableReference(Binding binding) Determine whether the clause contains a reference to a local variable binding that cannot be inlined
OrderByClause	copy(FLWORExpression flwor, RebindingMap rebindings) Create a copy of this clause
AtomicValue	evaluateSortKey(int n, XPathContext c) Callback for evaluating the sort keys
void	explain(ExpressionPresenter out) Diagnostic print of expression structure.
AtomicComparer[]	getAtomicComparers()
int	getClauseKey() Get a keyword identifying what kind of clause this is
TuplePull	getPullStream(TuplePull base, XPathContext context) Get a tuple stream that implements the functionality of this clause, taking its input from another tuple stream which this clause modifies
TuplePush	getPushStream(TuplePush destination, XPathContext context) Get a push-mode tuple stream that implements the functionality of this clause, supplying its output to another tuple stream
SortKeyDefinitionList	getSortKeyDefinitions()
TupleExpression	getTupleExpression()
void	processOperands(OperandProcessor processor) Process the subexpressions of this clause
java.lang.String	toString()
void	typeCheck(ExpressionVisitor visitor, ContextItemStaticInfo contextInfo) Type-check the expression

Methods inherited from class net.sf.saxon.expr.flwor.Clause

gatherVariableReferences, getConfiguration, getLocation, getPackageData, getRangeVariables, isRepeated, optimize, refineVariableType, setLocation, setPackageData, setRepeated, toShortString

Methods inherited from class java.lang.Object

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

Field Detail

SORT_KEYS_ROLE

public static final OperandRole SORT_KEYS_ROLE

Constructor Detail

OrderByClause

public OrderByClause(FLWORExpression flwor,
                     SortKeyDefinition[] sortKeys,
                     TupleExpression tupleExpression)

Method Detail

getClauseKey

public int getClauseKey()

Description copied from class: Clause

Get a keyword identifying what kind of clause this is

Specified by:

getClauseKey in class Clause

Returns:

the kind of clause

containsNonInlineableVariableReference

public boolean containsNonInlineableVariableReference(Binding binding)

Description copied from class: Clause

Determine whether the clause contains a reference to a local variable binding that cannot be inlined

Overrides:

containsNonInlineableVariableReference in class Clause

Parameters:

binding - the binding for the local variable in question

Returns:

true if this clause uses the variable in a way that does not permit inlining

copy

public OrderByClause copy(FLWORExpression flwor,
                          RebindingMap rebindings)

Description copied from class: Clause

Create a copy of this clause

Specified by:

copy in class Clause

Parameters:

flwor - the new FLWORExpression to contain the copied clause

Returns:

the copied clause

getSortKeyDefinitions

public SortKeyDefinitionList getSortKeyDefinitions()

getAtomicComparers

public AtomicComparer[] getAtomicComparers()

getTupleExpression

public TupleExpression getTupleExpression()

getPullStream

public TuplePull getPullStream(TuplePull base,
                               XPathContext context)

Get a tuple stream that implements the functionality of this clause, taking its input from another tuple stream which this clause modifies

Specified by:

getPullStream in class Clause

Parameters:

base - the input tuple stream

context - XQuery dynamic context

Returns:

the output tuple stream

getPushStream

public TuplePush getPushStream(TuplePush destination,
                               XPathContext context)

Get a push-mode tuple stream that implements the functionality of this clause, supplying its output to another tuple stream

Specified by:

getPushStream in class Clause

Parameters:

destination - the output tuple stream

context - XQuery dynamic context

Returns:

the push tuple stream that implements the functionality of this clause of the FLWOR expression

processOperands

public void processOperands(OperandProcessor processor)
                     throws XPathException

Process the subexpressions of this clause

Specified by:

processOperands in class Clause

Parameters:

processor - the expression processor used to process the subexpressions

Throws:

XPathException - if any error is detected

typeCheck

public void typeCheck(ExpressionVisitor visitor,
                      ContextItemStaticInfo contextInfo)
               throws XPathException

Type-check the expression

Overrides:

typeCheck in class Clause

Parameters:

visitor - the ExpressionVisitor, providing access to static context information

contextInfo - static information about the dynamic context

Throws:

XPathException - if any error is detected

addToPathMap

public void addToPathMap(PathMap pathMap,
                         PathMap.PathMapNodeSet pathMapNodeSet)

Description copied from class: Clause

Collect information about the navigation paths followed by this clause, for document projection purposes

Specified by:

addToPathMap in class Clause

Parameters:

pathMap - the path map in which the data is to be collected

pathMapNodeSet - the path map node set representing the paths to the context item

explain

public void explain(ExpressionPresenter out)
             throws XPathException

Diagnostic print of expression structure. The abstract expression tree is written to the supplied output destination.

Specified by:

explain in class Clause

Parameters:

out - the expression presenter used to display the structure

Throws:

XPathException

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

evaluateSortKey

public AtomicValue evaluateSortKey(int n,
                                   XPathContext c)
                            throws XPathException

Callback for evaluating the sort keys

Parameters:

n - identifies the sort key to be evaluated

c - the dynamic context for evaluation of the sort key

Returns:

the value of the sort key

Throws:

XPathException - if evaluation of the sort key fails