public class Minimax extends CollatingFunction
?????? | ????? |
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static int |
MAX |
static int |
MIN |
stringCollator
operation
argument
EVALUATE_METHOD, ITERATE_METHOD, locationId, PROCESS_METHOD, staticProperties
?????? |
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Minimax() |
?????? | ????? |
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void |
checkArguments(ExpressionVisitor visitor)
Static analysis: prevent sorting of the argument
|
int |
computeCardinality()
Determine the cardinality of the function.
|
Item |
evaluateItem(XPathContext context)
Evaluate the function
|
ItemType |
getItemType(TypeHierarchy th)
Determine the item type of the value returned by the function
|
boolean |
isIgnoreNaN()
Test whether NaN values are to be ignored
|
static AtomicValue |
minimax(SequenceIterator iter,
int operation,
AtomicComparer atomicComparer,
boolean ignoreNaN,
XPathContext context)
Static method to evaluate the minimum or maximum of a sequence
|
Expression |
optimize(ExpressionVisitor visitor,
ItemType contextItemType)
Perform optimisation of an expression and its subexpressions.
|
void |
setIgnoreNaN(boolean ignore)
Indicate whether NaN values should be ignored.
|
copy, getAtomicComparer, getCollator, getExpressionBaseURI, getStringCollator
addContextDocumentArgument, addDocToPathMap, computeSpecialProperties, getDetails, getErrorCodeForTypeErrors, getRequiredType, makeSystemFunction, setDetails, useContextItemAsDefault
addExternalFunctionCallToPathMap, checkArgumentCount, equals, explain, getArguments, getDisplayName, getFunctionName, getNumberOfArguments, hashCode, iterateSubExpressions, preEvaluate, promote, replaceSubExpression, setArguments, setFunctionName, simplify, simplifyArguments, toString, typeCheck
addToPathMap, adoptChildExpression, checkForUpdatingSubexpressions, checkPermittedContents, computeDependencies, computeStaticProperties, display, doPromotion, dynamicError, effectiveBooleanValue, evaluateAsString, evaluatePendingUpdates, explain, findParentOf, getCardinality, getColumnNumber, getColumnNumber, getConstructType, getContainer, getDependencies, getExecutable, getHostLanguage, getImplementationMethod, getIntrinsicDependencies, getLineNumber, getLineNumber, getLocationId, getLocationProvider, getObjectName, getProperties, getProperty, getPublicId, getSlotsUsed, getSpecialProperties, getSystemId, getSystemId, hasLoopingSubexpression, implementsStaticTypeCheck, isUpdatingExpression, iterate, iterateEvents, markTailFunctionCalls, process, resetLocalStaticProperties, setContainer, setFiltered, setFlattened, setLocationId, staticTypeCheck, suppressValidation, typeError
public void setIgnoreNaN(boolean ignore)
ignore
- true if NaN values are to be ignored when computing the min or max.public boolean isIgnoreNaN()
public void checkArguments(ExpressionVisitor visitor) throws XPathException
checkArguments
??? CollatingFunction
visitor
- the expression visitorXPathException
public int computeCardinality()
computeCardinality
??? SystemFunction
StaticProperty.ALLOWS_ZERO_OR_ONE
,
StaticProperty.EXACTLY_ONE
, StaticProperty.ALLOWS_ONE_OR_MORE
,
StaticProperty.ALLOWS_ZERO_OR_MORE
public Expression optimize(ExpressionVisitor visitor, ItemType contextItemType) throws XPathException
This method is called after all references to functions and variables have been resolved to the declaration of the function or variable, and after all type checking has been done.
optimize
??? SystemFunction
visitor
- an expression visitorcontextItemType
- 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
XPathException
- if an error is discovered during this phase
(typically a type error)public ItemType getItemType(TypeHierarchy th)
getItemType
??? SystemFunction
th
- the type hierarchy cachepublic Item evaluateItem(XPathContext context) throws XPathException
evaluateItem
???? EvaluableItem
evaluateItem
??? Expression
context
- The context in which the expression is to be evaluatedXPathException
- if any dynamic error occurs evaluating the
expressionpublic static AtomicValue minimax(SequenceIterator iter, int operation, AtomicComparer atomicComparer, boolean ignoreNaN, XPathContext context) throws XPathException
iter
- Iterator over the input sequenceoperation
- either MIN
or MAX
atomicComparer
- an AtomicComparer used to compare valuesignoreNaN
- true if NaN values are to be ignoredcontext
- dynamic evaluation contextXPathException
- typically if non-comparable values are found in the sequence