Class Idref

java.lang.Object

net.sf.saxon.expr.ComputedExpression

net.sf.saxon.expr.FunctionCall

net.sf.saxon.functions.SystemFunction

net.sf.saxon.functions.Idref

All Implemented Interfaces:

Serializable, SourceLocator, Container, Expression, InstructionInfoProvider

public class Idref
extends SystemFunction

See Also:

• Serialized Form

Field Summary

Fields inherited from class SystemFunction

operation

Fields inherited from class FunctionCall

argument

Fields inherited from class ComputedExpression

locationId, staticProperties

Fields inherited from interface Expression

EVALUATE_METHOD, ITERATE_METHOD, PROCESS_METHOD

Constructor Summary

Constructors

Constructor	Description
Idref()

Method Summary

Modifier and Type	Method	Description
void	checkArguments(StaticContext env)	Method called during static type checking
int	computeSpecialProperties()	Get the static properties of this expression (other than its type).
SequenceIterator	iterate(XPathContext context)	Enumerate the results of the expression
Expression	preEvaluate(StaticContext env)	preEvaluate: this method suppresses compile-time evaluation by doing nothing
Expression	simplify(StaticContext env)	Simplify: add a second implicit argument, the context document

Methods inherited from class SystemFunction

addContextDocumentArgument, computeCardinality, display, getDetails, getErrorCodeForTypeErrors, getItemType, getRequiredType, main, makeSystemFunction, setDetails, useContextItemAsDefault

Methods inherited from class FunctionCall

checkArgumentCount, getArguments, getDisplayName, getFunctionNameCode, getNumberOfArguments, iterateSubExpressions, optimize, promote, replaceSubExpression, setArguments, setFunctionNameCode, simplifyArguments, typeCheck

Methods inherited from class ComputedExpression

adoptChildExpression, checkPermittedContents, computeDependencies, computeStaticProperties, doPromotion, dynamicError, effectiveBooleanValue, evaluateAsString, evaluateItem, getCardinality, getColumnNumber, getConstructType, getDependencies, getExecutable, getHostLanguage, getImplementationMethod, getInstructionInfo, getIntrinsicDependencies, getLineNumber, getLocationId, getLocationProvider, getParentExpression, getPublicId, getSlotsUsed, getSpecialProperties, getSystemId, hasBadParentPointer, markTailFunctionCalls, process, resetStaticProperties, setLocationId, setParentExpression, setParentExpression, suppressValidation, typeError

Methods inherited from class Object

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

Constructor Details

Idref

public Idref()

Method Details

simplify

public Expression simplify(StaticContext env)
                    throws XPathException

Simplify: add a second implicit argument, the context document

Specified by:

simplify in interface Expression

Overrides:

simplify in class FunctionCall

Parameters:

env - the static context

Returns:

the simplified expression

Throws:

XPathException - if an error is discovered during expression rewriting

checkArguments

public void checkArguments(StaticContext env)
                    throws XPathException

Description copied from class: SystemFunction

Method called during static type checking

Overrides:

checkArguments in class SystemFunction

Throws:

XPathException

computeSpecialProperties

public int computeSpecialProperties()

Get the static properties of this expression (other than its type). The result is bit-signficant. These properties are used for optimizations. In general, if property bit is set, it is true, but if it is unset, the value is unknown.

Overrides:

computeSpecialProperties in class SystemFunction

preEvaluate

public Expression preEvaluate(StaticContext env)

preEvaluate: this method suppresses compile-time evaluation by doing nothing

Overrides:

preEvaluate in class FunctionCall

iterate

public SequenceIterator iterate(XPathContext context)
                         throws XPathException

Enumerate the results of the expression

Specified by:

iterate in interface Expression

Overrides:

iterate in class ComputedExpression

Parameters:

context - supplies the context for evaluation

Returns:

a SequenceIterator that can be used to iterate over the result of the expression

Throws:

XPathException - if any dynamic error occurs evaluating the expression