public final class Atomizer extends UnaryExpression
Modifier and Type | Class and Description |
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static class |
Atomizer.AtomizingFunction
Implement the mapping function.
|
operand
locationId, staticProperties
EVALUATE_METHOD, ITERATE_METHOD, PROCESS_METHOD
Constructor and Description |
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Atomizer(Expression sequence,
Configuration config)
Constructor
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Modifier and Type | Method and Description |
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int |
computeCardinality()
Determine the static cardinality of the expression
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int |
computeSpecialProperties()
Determine the special properties of this expression
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protected java.lang.String |
displayOperator(Configuration config)
Give a string representation of the operator for use in diagnostics
|
Item |
evaluateItem(XPathContext context)
Evaluate as an Item.
|
static ItemType |
getAtomizedItemType(Expression operand,
boolean alwaysUntyped,
TypeHierarchy th)
Compute the type that will result from atomizing the result of a given expression
|
ItemType |
getItemType(TypeHierarchy th)
Determine the data type of the items returned by the expression, if possible
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SequenceIterator |
iterate(XPathContext context)
Iterate over the sequence of values
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Expression |
simplify(StaticContext env)
Simplify an expression
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Expression |
typeCheck(StaticContext env,
ItemType contextItemType)
Type-check the expression
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display, equals, getBaseExpression, hashCode, iterateSubExpressions, optimize, promote, replaceSubExpression
adoptChildExpression, checkPermittedContents, computeDependencies, computeStaticProperties, doPromotion, dynamicError, effectiveBooleanValue, evaluateAsString, getCardinality, getColumnNumber, getConstructType, getDependencies, getExecutable, getHostLanguage, getImplementationMethod, getInstructionInfo, getIntrinsicDependencies, getLineNumber, getLocationId, getLocationProvider, getParentExpression, getPublicId, getSlotsUsed, getSpecialProperties, getSystemId, hasBadParentPointer, markTailFunctionCalls, process, resetStaticProperties, setLocationId, setParentExpression, setParentExpression, suppressValidation, typeError
public Atomizer(Expression sequence, Configuration config)
sequence
- the sequence to be atomizedconfig
- the Configuration. Used only for optimization, may be null. Atomization is faster if
it is known in advance that all nodes will be untyped.public Expression simplify(StaticContext env) throws XPathException
simplify
in interface Expression
simplify
in class UnaryExpression
env
- the static contextXPathException
- if an error is discovered during expression
rewritingpublic Expression typeCheck(StaticContext env, ItemType contextItemType) throws XPathException
typeCheck
in interface Expression
typeCheck
in class UnaryExpression
env
- the static context of the expressioncontextItemType
- 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
StaticError
- if an error is discovered during this phase
(typically a type error)XPathException
public int computeSpecialProperties()
computeSpecialProperties
in class UnaryExpression
StaticProperty.NON_CREATIVE
.public SequenceIterator iterate(XPathContext context) throws XPathException
iterate
in interface Expression
iterate
in class ComputedExpression
context
- supplies the context for evaluationXPathException
- if any dynamic error occurs evaluating the
expressionpublic Item evaluateItem(XPathContext context) throws XPathException
evaluateItem
in interface Expression
evaluateItem
in class ComputedExpression
context
- The context in which the expression is to be evaluatedXPathException
- if any dynamic error occurs evaluating the
expressionpublic ItemType getItemType(TypeHierarchy th)
getItemType
in interface Expression
getItemType
in class UnaryExpression
th
- public static final ItemType getAtomizedItemType(Expression operand, boolean alwaysUntyped, TypeHierarchy th)
operand
- the given expressionalwaysUntyped
- true if it is known that nodes will always be untypedpublic int computeCardinality()
computeCardinality
in class UnaryExpression
protected java.lang.String displayOperator(Configuration config)
displayOperator
in class UnaryExpression
config
-