com.saxonica.expr
Class OuterForExpression

java.lang.Object
  extended by net.sf.saxon.expr.Expression
      extended by net.sf.saxon.expr.Assignation
          extended by net.sf.saxon.expr.ForExpression
              extended by com.saxonica.expr.OuterForExpression
All Implemented Interfaces:
Serializable, SourceLocator, LocationProvider, SaxonLocator, Binding, InstructionInfo, Locator

public class OuterForExpression
extends ForExpression

Expression class that implements the "outer for" clause of XQuery 1.1

See Also:
Serialized Form

Nested Class Summary
 
Nested classes/interfaces inherited from class net.sf.saxon.expr.ForExpression
ForExpression.EventMappingAction, ForExpression.MappingAction
 
Field Summary
 
Fields inherited from class net.sf.saxon.expr.ForExpression
positionVariable
 
Fields inherited from class net.sf.saxon.expr.Assignation
action, requiredType, sequence, slotNumber, variableName
 
Fields inherited from class net.sf.saxon.expr.Expression
EFFECTIVE_BOOLEAN_VALUE, EVALUATE_METHOD, EVENT_FEED_METHOD, ITEM_FEED_METHOD, ITERATE_METHOD, locationId, MAX_SEQUENCE_LENGTH, MAX_STRING_LENGTH, PROCESS_METHOD, PUSH_SELECTION, staticProperties, UNBOUNDED_LOWER, UNBOUNDED_UPPER, WATCH_METHOD
 
Constructor Summary
OuterForExpression()
           
 
Method Summary
 Expression copy()
          Copy an expression.
 void evaluatePendingUpdates(XPathContext context, PendingUpdateList pul)
          Evaluate an updating expression, adding the results to a Pending Update List.
protected  void explainSpecializedAttributes(ExpressionPresenter out)
           
protected  int getRangeVariableCardinality()
          Get the cardinality of the range variable
 SequenceIterator iterate(XPathContext context)
          Iterate over the result of the expression
 EventIterator iterateEvents(XPathContext context)
          Deliver the result of the expression as a sequence of events.
 Expression optimize(ExpressionVisitor visitor, ExpressionVisitor.ContextItemType contextItemType)
          Optimize the expression
 void process(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, explain, extendBindingList, getConstructType, getExpressionName, getImplementationMethod, getIntegerBounds, getItemType, getPositionVariable, getPositionVariableName, getRequiredSlots, hasLoopingSubexpression, hasVariableBinding, isVacuousExpression, markTailFunctionCalls, setPositionVariable, setSlotNumber, toString, typeCheck
 
Methods inherited from class net.sf.saxon.expr.Assignation
addReference, addToPathMap, checkForUpdatingSubexpressions, evaluateVariable, getAction, getIntegerBoundsForVariable, getLocalSlotNumber, getNominalReferenceCount, getObjectName, getRequiredType, getSequence, getVariableName, getVariableQName, isAssignable, isGlobal, isIndexedVariable, isUpdatingExpression, iterateSubExpressions, promote, promoteWhereClause, refineTypeInformation, replaceSubExpression, replaceVariable, setAction, setIndexedVariable, setRequiredType, setSequence, setVariableQName, simplify, suppressValidation
 
Methods inherited from class net.sf.saxon.expr.Expression
adoptChildExpression, computeDependencies, computeSpecialProperties, computeStaticProperties, doPromotion, dynamicError, effectiveBooleanValue, evaluateAsString, evaluateItem, explain, getCardinality, getColumnNumber, getColumnNumber, getContainer, getDependencies, getEvaluationMethod, getExecutable, getHostLanguage, getIntrinsicDependencies, getLineNumber, getLineNumber, getLocationId, getLocationProvider, getProperties, getProperty, getPublicId, getSlotsUsed, getSpecialProperties, getSystemId, getSystemId, implementsStaticTypeCheck, isSubtreeExpression, iterateSameFocusSubExpressions, resetLocalStaticProperties, setContainer, setEvaluationMethod, setFiltered, setFlattened, setLocationId, staticTypeCheck, typeError
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Constructor Detail

OuterForExpression

public OuterForExpression()
Method Detail

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,
                           ExpressionVisitor.ContextItemType 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()
Copy an expression. This makes a deep copy.

Overrides:
copy in class ForExpression
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

iterateEvents

public EventIterator iterateEvents(XPathContext context)
                            throws XPathException
Deliver the result of the expression as a sequence of events.

Overrides:
iterateEvents in class ForExpression
Parameters:
context - The dynamic evaluation context
Returns:
the result of the expression as an iterator over a sequence of PullEvent objects
Throws:
XPathException - if a dynamic error occurs during expression evaluation

process

public void process(XPathContext context)
             throws XPathException
Process this expression as an instruction, writing results to the current outputter

Overrides:
process in class ForExpression
Parameters:
context - The dynamic context, giving access to the current node, the current variables, etc.
Throws:
XPathException - if a dynamic error occurs

evaluatePendingUpdates

public void evaluatePendingUpdates(XPathContext context,
                                   PendingUpdateList pul)
                            throws XPathException
Evaluate an updating expression, adding the results to a Pending Update List. The default implementation of this method, which is used for non-updating expressions, throws an UnsupportedOperationException

Overrides:
evaluatePendingUpdates in class ForExpression
Parameters:
context - the XPath dynamic evaluation context
pul - the pending update list to which the results should be written
Throws:
XPathException - if evaluation fails

explainSpecializedAttributes

protected void explainSpecializedAttributes(ExpressionPresenter out)
Overrides:
explainSpecializedAttributes in class ForExpression


Copyright (c) 2004-2011 Saxonica Limited. All rights reserved.