net.sf.saxon.expr
Class LocalVariableReference

java.lang.Object
  net.sf.saxon.expr.Expression
      net.sf.saxon.expr.VariableReference
          net.sf.saxon.expr.LocalVariableReference

All Implemented Interfaces:

Serializable, SourceLocator, BindingReference, EvaluableItem, SequenceIterable, InstructionInfoProvider

public class LocalVariableReference
extends VariableReference

Variable reference: a reference to a local variable. This subclass of VariableReference bypasses the Binding object to get the value directly from the relevant slot in the local stackframe.

See Also:

Serialized Form

Field Summary

Fields inherited from class net.sf.saxon.expr.Expression

EVALUATE_METHOD, ITERATE_METHOD, PROCESS_METHOD

Constructor Summary

LocalVariableReference()
Create a local variable reference.

LocalVariableReference(Binding binding)
Create a LocalVariableReference bound to a given Binding

Method Summary

ValueRepresentation	evaluateVariable(XPathContext c) Return the value of the variable
int	getSlotNumber() Get the slot number allocated to this local variable
void	refineVariableReference() Replace this VariableReference where appropriate by a more efficient implementation.
void	setSlotNumber(int slotNumber) Set the slot number for this local variable, that is, its position in the local stack frame

Methods inherited from class net.sf.saxon.expr.VariableReference

addToPathMap, computeCardinality, computeSpecialProperties, copy, equals, evaluateItem, explain, fixup, getBinding, getDisplayName, getImplementationMethod, getIntrinsicDependencies, getItemType, hashCode, isFiltered, isFlattened, isInLoop, iterate, optimize, process, promote, refineVariableReference, refineVariableType, setFiltered, setFlattened, setStaticType, toString, typeCheck

Methods inherited from class net.sf.saxon.expr.Expression

adoptChildExpression, checkPermittedContents, computeDependencies, computeStaticProperties, display, doPromotion, effectiveBooleanValue, evaluateAsString, explain, findParentOf, getCardinality, getColumnNumber, getContainer, getDependencies, getExecutable, getHostLanguage, getInstructionInfo, getLineNumber, getLocationId, getLocationProvider, getPublicId, getSlotsUsed, getSpecialProperties, getSystemId, hasLoopingSubexpression, implementsStaticTypeCheck, iterateEvents, iterateSubExpressions, markTailFunctionCalls, replaceSubExpression, setContainer, setLocationId, simplify, staticTypeCheck, suppressValidation

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

LocalVariableReference

public LocalVariableReference()

Create a local variable reference. The binding and slot number will be supplied later

LocalVariableReference

public LocalVariableReference(Binding binding)

Create a LocalVariableReference bound to a given Binding

Parameters:

binding - the binding (that is, the declaration of this local variable)

Method Detail

setSlotNumber

public void setSlotNumber(int slotNumber)

Set the slot number for this local variable, that is, its position in the local stack frame

Parameters:

slotNumber - the slot number to be used

getSlotNumber

public int getSlotNumber()

Get the slot number allocated to this local variable

Returns:

the slot number

evaluateVariable

public ValueRepresentation evaluateVariable(XPathContext c)
                                     throws XPathException

Return the value of the variable

Overrides:

evaluateVariable in class VariableReference

Parameters:

c - the XPath dynamic context

Returns:

the value of the variable

Throws:

XPathException - if any dynamic error occurs while evaluating the variable

refineVariableReference

public void refineVariableReference()

Replace this VariableReference where appropriate by a more efficient implementation.