public class Average extends Aggregate implements CallableExpression
operation
argument
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 and Description |
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Average() |
Modifier and Type | Method and Description |
---|---|
static AtomicValue |
average(SequenceIterator iter,
XPathContext context,
SourceLocator location)
Calculate average
|
SequenceIterator |
call(SequenceIterator[] arguments,
XPathContext context)
Evaluate the expression
|
int |
computeCardinality()
Determine the cardinality of the function.
|
Item |
evaluateItem(XPathContext context)
Evaluate the function
|
int |
getImplementationMethod()
An implementation of Expression must provide at least one of the methods evaluateItem(), iterate(), or process().
|
ItemType |
getItemType(TypeHierarchy th)
Determine the item type of the value returned by the function
|
checkArguments
addContextDocumentArgument, addDocToPathMap, computeSpecialProperties, copy, equals, getDetails, getErrorCodeForTypeErrors, getOperation, getRequiredType, makeSystemFunction, optimize, setDetails, useContextItemAsDefault
addExternalFunctionCallToPathMap, checkArgumentCount, explain, getArguments, getDisplayName, getExpressionName, getFunctionName, getNumberOfArguments, hashCode, iterateSubExpressions, preEvaluate, promote, replaceSubExpression, setArguments, setFunctionName, simplify, simplifyArguments, toString, typeCheck
addToPathMap, adoptChildExpression, checkForUpdatingSubexpressions, checkPermittedContents, computeDependencies, computeStaticProperties, doPromotion, dynamicError, effectiveBooleanValue, evaluateAsString, evaluatePendingUpdates, explain, getCardinality, getColumnNumber, getColumnNumber, getConstructType, getContainer, getDependencies, getEvaluationMethod, getExecutable, getHostLanguage, getIntegerBounds, getIntrinsicDependencies, getLineNumber, getLineNumber, getLocationId, getLocationProvider, getObjectName, getProperties, getProperty, getPublicId, getSlotsUsed, getSpecialProperties, getSystemId, getSystemId, hasLoopingSubexpression, hasVariableBinding, implementsStaticTypeCheck, isSubtreeExpression, isUpdatingExpression, isVacuousExpression, iterate, iterateEvents, iterateSameFocusSubExpressions, markTailFunctionCalls, process, resetLocalStaticProperties, setContainer, setEvaluationMethod, setFiltered, setFlattened, setLocationId, staticTypeCheck, suppressValidation, typeError
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
getArguments
public int getImplementationMethod()
SystemFunction
getImplementationMethod
in class SystemFunction
Expression.ITERATE_METHOD
or Expression.EVALUATE_METHOD
or
Expression.PROCESS_METHOD
public ItemType getItemType(TypeHierarchy th)
getItemType
in class SystemFunction
th
- the type hierarchy cachepublic int computeCardinality()
computeCardinality
in class SystemFunction
StaticProperty.ALLOWS_ZERO_OR_ONE
,
StaticProperty.EXACTLY_ONE
, StaticProperty.ALLOWS_ONE_OR_MORE
,
StaticProperty.ALLOWS_ZERO_OR_MORE
public Item evaluateItem(XPathContext context) throws XPathException
evaluateItem
in class Expression
context
- The context in which the expression is to be evaluatedXPathException
- if any dynamic error occurs evaluating the
expressionpublic static AtomicValue average(SequenceIterator iter, XPathContext context, SourceLocator location) throws XPathException
iter
- iterator over the items to be totalledcontext
- the XPath dynamic contextlocation
- location of the expression in the source for diagnosticsXPathException
public SequenceIterator call(SequenceIterator[] arguments, XPathContext context) throws XPathException
CallableExpression
call
in interface CallableExpression
arguments
- the values of the arguments, supplied as SequenceIteratorscontext
- the dynamic evaluation contextXPathException
- if a dynamic error occurs during the evaluation of the expression