Package net.sf.saxon.expr

Class GlobalVariableReference

java.lang.Object

net.sf.saxon.expr.Expression

net.sf.saxon.expr.VariableReference

net.sf.saxon.expr.GlobalVariableReference

All Implemented Interfaces:

BindingReference, ComponentInvocation, ExportAgent, Locatable, IdentityComparable, Traceable

public class GlobalVariableReference
extends VariableReference
implements ComponentInvocation

A reference to a global variable

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	GlobalVariableReference.GlobalVariableReferenceElaborator	Elaborator for a global variable reference, for example $globalVar.

Field Summary

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

binding, constantValue, staticType

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

EFFECTIVE_BOOLEAN_VALUE, EVALUATE_METHOD, ITEM_FEED_METHOD, ITERATE_METHOD, MAX_COST, MAX_SEQUENCE_LENGTH, MAX_STRING_LENGTH, PROCESS_METHOD, staticProperties, UNBOUNDED_LOWER, UNBOUNDED_UPPER, UPDATE_METHOD, WATCH_METHOD

Constructor Summary

Constructors

Constructor	Description
GlobalVariableReference(GlobalVariable var)
GlobalVariableReference(StructuredQName name)

Method Summary

Modifier and Type	Method	Description
Expression	copy(RebindingMap rebindings)	Create a clone copy of this VariableReference
GroundedValue	evaluateVariable(XPathContext c)	Evaluate this variable
void	export(ExpressionPresenter out)	Diagnostic print of expression structure.
int	getBindingSlot()	Get the binding slot to be used.
Elaborator	getElaborator()	Make an elaborator for this expression
java.lang.String	getExpressionName()	Get a name identifying the kind of expression, in terms meaningful to a user.
Component	getFixedTarget()	Get the target component if this is known in advance, that is, if the target component is private or final, or in some other cases such as xsl:original.
java.util.Set<Expression>	getPreconditions()
SymbolicName	getSymbolicName()	Get the symbolic name of the component that this invocation references
Component	getTarget()
void	setBindingSlot(int slot)	Set the binding slot to be used.
void	setTarget(Component target)

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

addToPathMap, computeCardinality, computeHashCode, computeSpecialProperties, copyFrom, equals, evaluateItem, fixup, getBinding, getDisplayName, getEQName, getImplementationMethod, getIntegerBounds, getIntrinsicDependencies, getItemType, getNetCost, getScopingExpression, getStaticUType, getStreamerName, getVariableName, isFiltered, isFlattened, isInLoop, iterate, optimize, process, recomputeInLoop, refineVariableType, setFiltered, setFlattened, setInLoop, setStaticType, setVariableName, supportsLazyEvaluation, toShortString, toString, typeCheck

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

adoptChildExpression, allowExtractingCommonSubexpressions, checkedOperands, checkForUpdatingSubexpressions, checkPermittedContents, computeDependencies, computeStaticProperties, dispatchTailCall, dynamicError, effectiveBooleanValue, evaluateAsString, explain, getCardinality, getConfiguration, getCost, getDependencies, getEvaluationMethod, getExtraProperty, getLocalRetainedStaticContext, getLocation, getObjectName, getPackageData, getParentExpression, getProperties, getProperty, getRetainedStaticContext, getSlotsUsed, getSpecialProperties, getStaticBaseURI, getStaticBaseURIString, getStaticType, getTracingTag, hasCompatibleStaticContext, hashCode, hasSpecialProperty, hasVariableBinding, identityHashCode, implementsStaticTypeCheck, isCallOn, isEqual, isIdentical, isInstruction, isLiftable, isMultiThreaded, isStaticPropertiesKnown, isSubtreeExpression, isUpdatingExpression, isVacuousExpression, makeElaborator, markTailFunctionCalls, operandList, operands, operandSparseList, optimizeChildren, prepareForStreaming, resetLocalStaticProperties, restoreParentPointers, setEvaluationMethod, setExtraProperty, setLocation, setParentExpression, setRetainedStaticContext, setRetainedStaticContextLocally, setRetainedStaticContextThoroughly, setStaticProperty, simplify, simplifyChildren, staticTypeCheck, suppressValidation, toPattern, typeCheckChildren, typeError, unordered, verifyParentPointers, withLocation

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface net.sf.saxon.trace.Traceable

gatherProperties

Constructor Detail

GlobalVariableReference

public GlobalVariableReference(StructuredQName name)

GlobalVariableReference

public GlobalVariableReference(GlobalVariable var)

Method Detail

copy

public Expression copy(RebindingMap rebindings)

Description copied from class: VariableReference

Create a clone copy of this VariableReference

Specified by:

copy in class VariableReference

Parameters:

rebindings - variables that need to switch to new bindings

Returns:

the cloned copy

setBindingSlot

public void setBindingSlot(int slot)

Set the binding slot to be used. This is the offset within the binding vector of the containing component where the actual target component is to be found. The target template is not held directly in the invocation instruction/expression itself because it can be overridden in a using package.

Specified by:

setBindingSlot in interface ComponentInvocation

Parameters:

slot - the offset in the binding vector of the containing package where the target component can be found.

getBindingSlot

public int getBindingSlot()

Get the binding slot to be used. This is the offset within the binding vector of the containing component where the actual target component is to be found.

Specified by:

getBindingSlot in interface ComponentInvocation

Returns:

the offset in the binding vector of the containing package where the target component can be found.

getSymbolicName

public SymbolicName getSymbolicName()

Get the symbolic name of the component that this invocation references

Specified by:

getSymbolicName in interface ComponentInvocation

Returns:

the symbolic name of the target component

setTarget

public void setTarget(Component target)

getTarget

public Component getTarget()

getFixedTarget

public Component getFixedTarget()

Description copied from interface: ComponentInvocation

Get the target component if this is known in advance, that is, if the target component is private or final, or in some other cases such as xsl:original. Otherwise, return null.

Specified by:

getFixedTarget in interface ComponentInvocation

Returns:

the bound component if the binding has been fixed

evaluateVariable

public GroundedValue evaluateVariable(XPathContext c)
                               throws XPathException

Evaluate this variable

Overrides:

evaluateVariable in class VariableReference

Parameters:

c - the XPath dynamic context

Returns:

the value of the variable

Throws:

XPathException - if any error occurs

export

public void export(ExpressionPresenter out)
            throws XPathException

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

Specified by:

export in interface ExportAgent

Overrides:

export in class VariableReference

Parameters:

out - the expression presenter used to display the structure

Throws:

XPathException - if the export fails, for example if an expression is found that won't work in the target environment.

getPreconditions

public java.util.Set<Expression> getPreconditions()

getExpressionName

public java.lang.String getExpressionName()

Get a name identifying the kind of expression, in terms meaningful to a user.

Overrides:

getExpressionName in class VariableReference

Returns:

a name identifying the kind of expression, in terms meaningful to a user. The name will always be in the form of a lexical XML QName, and should match the name used in export() output displaying the expression.

getElaborator

public Elaborator getElaborator()

Make an elaborator for this expression

Overrides:

getElaborator in class Expression

Returns:

a suitable elaborator