Package net.sf.saxon.expr.flwor

Class OuterForExpression

java.lang.Object

net.sf.saxon.expr.Expression

net.sf.saxon.expr.Assignation

net.sf.saxon.expr.ForExpression

net.sf.saxon.expr.flwor.OuterForExpression

All Implemented Interfaces:

Binding, ExportAgent, LocalBinding, Locatable, IdentityComparable, Traceable

public class OuterForExpression
extends ForExpression

Expression class that implements the "outer for" clause of XQuery 3.0

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	OuterForExpression.OuterForExprElaborator	An elaborator for a "for" expression, typically written as {for $x in SEQ return R}.

Nested classes/interfaces inherited from class net.sf.saxon.expr.ForExpression

ForExpression.ForExprElaborator, ForExpression.MappingAction

Field Summary

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

hasLoopingReference, indexedVariable, references, requiredType, slotNumber, variableName

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
OuterForExpression()

Method Summary

Modifier and Type	Method	Description
protected String	allowingEmptyString()
Expression	copy(RebindingMap rebindings)	Copy an expression.
protected void	explainSpecializedAttributes(ExpressionPresenter out)
Elaborator	getElaborator()	Make an elaborator for this expression
String	getExpressionName()	Get a name identifying the kind of expression, in terms meaningful to a user.
protected int	getRangeVariableCardinality()	Get the cardinality of the range variable
SequenceIterator	iterate(XPathContext context)	Iterate over the result of the expression
Expression	optimize(ExpressionVisitor visitor, ContextItemStaticInfo contextItemType)	Optimize the expression
void	process(Outputter output, XPathContext context)	Process this expression as an instruction, writing results to the current outputter

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

checkPermittedContents, computeCardinality, export, getImplementationMethod, getIntegerBounds, getItemType, getStaticUType, getStreamerName, isVacuousExpression, markTailFunctionCalls, toShortString, toString, typeCheck, unordered

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

addReference, addToPathMap, checkForUpdatingSubexpressions, computeDependencies, evaluateVariable, getAction, getActionOp, getCost, getIntegerBoundsForVariable, getLocalSlotNumber, getNominalReferenceCount, getObjectName, getRequiredSlots, getRequiredType, getSequence, getSequenceOp, getVariableEQName, getVariableName, getVariableQName, hasVariableBinding, isAssignable, isGlobal, isIndexedVariable, isUpdatingExpression, operands, rebuildReferenceList, refineTypeInformation, removeDeadReferences, replaceVariable, setAction, setIndexedVariable, setRequiredType, setSequence, setSlotNumber, setVariableQName, suppressValidation, verifyReferences

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

adoptChildExpression, allowExtractingCommonSubexpressions, checkedOperands, computeHashCode, computeSpecialProperties, computeStaticProperties, dispatchTailCall, dynamicError, effectiveBooleanValue, equals, evaluateAsString, evaluateItem, explain, getCardinality, getConfiguration, getDependencies, getEvaluationMethod, getExtraProperty, getIntrinsicDependencies, getLocalRetainedStaticContext, getLocation, getNetCost, getPackageData, getParentExpression, getProperties, getProperty, getRetainedStaticContext, getScopingExpression, getSlotsUsed, getSpecialProperties, getStaticBaseURI, getStaticBaseURIString, getStaticType, getTracingTag, hasCompatibleStaticContext, hashCode, hasSpecialProperty, identityHashCode, implementsStaticTypeCheck, isCallOn, isEqual, isIdentical, isInstruction, isLiftable, isMultiThreaded, isStaticPropertiesKnown, isSubtreeExpression, makeElaborator, operandList, operandSparseList, optimizeChildren, prepareForStreaming, resetLocalStaticProperties, restoreParentPointers, setEvaluationMethod, setExtraProperty, setFiltered, setFlattened, setLocation, setParentExpression, setRetainedStaticContext, setRetainedStaticContextLocally, setRetainedStaticContextThoroughly, setStaticProperty, simplify, simplifyChildren, staticTypeCheck, supportsLazyEvaluation, toPattern, typeCheckChildren, typeError, 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 Details

OuterForExpression

public OuterForExpression()

Method Details

getRangeVariableCardinality

protected int getRangeVariableCardinality()

Get the cardinality of the range variable

Overrides:

getRangeVariableCardinality in class ForExpression

Returns:

the cardinality of the range variable (StaticProperty.EXACTLY_ONE). in a subclass

optimize

public Expression optimize(ExpressionVisitor visitor,
 ContextItemStaticInfo contextItemType)
                    throws XPathException

Optimize the expression

Overrides:

optimize in class ForExpression

Parameters:

visitor - an expression visitor

contextItemType - the static type of "." at the point where this expression is invoked. The parameter is set to null if it is known statically that the context item will be undefined. If the type of the context item is not known statically, the argument is set to Type.ITEM_TYPE

Returns:

the original expression, rewritten if appropriate to optimize execution

Throws:

XPathException - if an error is discovered during this phase (typically a type error)

copy

public Expression copy(RebindingMap rebindings)

Copy an expression. This makes a deep copy.

Overrides:

copy in class ForExpression

Parameters:

rebindings - the rebinding map

Returns:

the copy of the original expression

iterate

public SequenceIterator iterate(XPathContext context)
                         throws XPathException

Iterate over the result of the expression

Overrides:

iterate in class ForExpression

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

process

public void process(Outputter output,
 XPathContext context)
             throws XPathException

Process this expression as an instruction, writing results to the current outputter

Overrides:

process in class ForExpression

Parameters:

output - the destination for the result

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

Throws:

XPathException - if a dynamic error occurs

getExpressionName

public String getExpressionName()

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

Overrides:

getExpressionName in class ForExpression

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 explain() output displaying the expression.

allowingEmptyString

protected String allowingEmptyString()

Overrides:

allowingEmptyString in class ForExpression

explainSpecializedAttributes

protected void explainSpecializedAttributes(ExpressionPresenter out)

Overrides:

explainSpecializedAttributes in class ForExpression

getElaborator

public Elaborator getElaborator()

Make an elaborator for this expression

Overrides:

getElaborator in class ForExpression

Returns:

a suitable elaborator