net.sf.saxon.instruct
Class LocalParam

java.lang.Object
  net.sf.saxon.expr.Expression
      net.sf.saxon.instruct.Instruction
          net.sf.saxon.instruct.GeneralVariable
              net.sf.saxon.instruct.LocalParam

All Implemented Interfaces:

Serializable, SourceLocator, Binding, Container, EvaluableItem, SequenceIterable, TailCallReturner, InstructionInfoProvider

public final class LocalParam
extends GeneralVariable

The compiled form of an xsl:param element in the stylesheet or an external variable in a Query.
The xsl:param element in XSLT has mandatory attribute name and optional attribute select. It can also be specified as required="yes" or required="no". In standard XQuery external variables are always required, and no default value can be specified; but Saxon provides an extension pragma that allows a query to specify a default.

See Also:

Serialized Form

Field Summary

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

EVALUATE_METHOD, ITERATE_METHOD, PROCESS_METHOD

Constructor Summary

LocalParam()

Method Summary

ValueRepresentation	evaluateVariable(XPathContext c) Evaluate the variable
int	getInstructionNameCode() Get the name of this instruction for diagnostic and tracing purposes
Iterator	iterateSubExpressions() Get all the XPath expressions associated with this instruction (in XSLT terms, the expression present on attributes of the instruction, as distinct from the child instructions in a sequence construction)
TailCall	processLeavingTail(XPathContext context) Process the local parameter declaration
boolean	replaceSubExpression(Expression original, Expression replacement) Replace one subexpression by a replacement subexpression
void	setConversion(Expression convertor) Define a conversion that is to be applied to the supplied parameter value.

Methods inherited from class net.sf.saxon.instruct.GeneralVariable

display, evaluateItem, getCardinality, getItemType, getLocalSlotNumber, getNameCode, getRequiredType, getSelectExpression, getSelectValue, getSlotNumber, getVariableFingerprint, getVariableName, init, isAssignable, isGlobal, isImplicitlyRequiredParam, isRequiredParam, isTunnelParam, iterate, optimize, setAssignable, setImplicitlyRequiredParam, setNameCode, setReferenceCount, setRequiredParam, setRequiredType, setSelectExpression, setSlotNumber, setTunnel, setVariableName, simplify, typeCheck

Methods inherited from class net.sf.saxon.instruct.Instruction

appendItem, computeCardinality, computeSpecialProperties, createsNewNodes, evaluateAsString, getImplementationMethod, getInstructionInfo, getSourceLocator, isXSLT, process, promote

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

adoptChildExpression, checkPermittedContents, computeDependencies, computeStaticProperties, doPromotion, effectiveBooleanValue, getColumnNumber, getContainingProcedure, getDependencies, getExecutable, getHostLanguage, getIntrinsicDependencies, getLineNumber, getLocationId, getLocationProvider, getParentExpression, getPublicId, getSlotsUsed, getSpecialProperties, getSystemId, hasBadParentPointer, markTailFunctionCalls, resetStaticProperties, setLocationId, setParentExpression, setParentExpression, suppressValidation

Methods inherited from class java.lang.Object

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

Methods inherited from interface javax.xml.transform.SourceLocator

getColumnNumber, getLineNumber, getPublicId, getSystemId

Constructor Detail

LocalParam

public LocalParam()

Method Detail

setConversion

public void setConversion(Expression convertor)

Define a conversion that is to be applied to the supplied parameter value.

Parameters:

convertor -

getInstructionNameCode

public int getInstructionNameCode()

Get the name of this instruction for diagnostic and tracing purposes

Overrides:

getInstructionNameCode in class GeneralVariable

iterateSubExpressions

public Iterator iterateSubExpressions()

Get all the XPath expressions associated with this instruction (in XSLT terms, the expression present on attributes of the instruction, as distinct from the child instructions in a sequence construction)

Overrides:

iterateSubExpressions in class GeneralVariable

Returns:

an iterator containing the sub-expressions of this expression

replaceSubExpression

public boolean replaceSubExpression(Expression original,
                                    Expression replacement)

Replace one subexpression by a replacement subexpression

Specified by:

replaceSubExpression in interface Container

Overrides:

replaceSubExpression in class GeneralVariable

Parameters:

original - the original subexpression

replacement - the replacement subexpression

Returns:

true if the original subexpression is found

processLeavingTail

public TailCall processLeavingTail(XPathContext context)
                            throws XPathException

Process the local parameter declaration

Specified by:

processLeavingTail in interface TailCallReturner

Specified by:

processLeavingTail in class Instruction

Parameters:

context - The dynamic context of the transformation, giving access to the current node, the current variables, etc.

Returns:

null if the instruction has completed execution; or a TailCall indicating a function call or template call that is delegated to the caller, to be made after the stack has been unwound so as to save stack space.

Throws:

XPathException

evaluateVariable

public ValueRepresentation evaluateVariable(XPathContext c)

Evaluate the variable