public class AtomicSequenceConverter extends UnaryExpression
Modifier and Type | Class and Description |
---|---|
static class |
AtomicSequenceConverter.AtomicSequenceMappingFunction
Mapping function wrapped around a converter
|
static class |
AtomicSequenceConverter.ToStringMappingFunction
Mapping function that converts every item in a sequence to a string
|
Modifier and Type | Field and Description |
---|---|
protected Converter |
converter |
static AtomicSequenceConverter.ToStringMappingFunction |
TO_STRING_MAPPER |
EFFECTIVE_BOOLEAN_VALUE, EVALUATE_METHOD, ITEM_FEED_METHOD, ITERATE_METHOD, MAX_SEQUENCE_LENGTH, MAX_STRING_LENGTH, PROCESS_METHOD, staticProperties, UNBOUNDED_LOWER, UNBOUNDED_UPPER, UPDATE_METHOD, WATCH_METHOD
Constructor and Description |
---|
AtomicSequenceConverter(Expression sequence,
PlainType requiredItemType)
Constructor
|
Modifier and Type | Method and Description |
---|---|
Converter |
allocateConverter(Configuration config,
boolean allowNull) |
Converter |
allocateConverter(Configuration config,
boolean allowNull,
ItemType sourceType) |
int |
computeCardinality()
Determine the static cardinality of the expression
|
int |
computeHashCode()
get HashCode for comparing two expressions.
|
int |
computeSpecialProperties()
Determine the special properties of this expression
|
Expression |
copy(RebindingMap rebindings)
Copy an expression.
|
protected java.lang.String |
displayOperator(Configuration config)
Give a string representation of the operator for use in diagnostics
|
boolean |
equals(java.lang.Object other)
Is this expression the same as another expression?
|
AtomicValue |
evaluateItem(XPathContext context)
Evaluate as an Item.
|
void |
export(ExpressionPresenter destination)
Diagnostic print of expression structure.
|
Converter |
getConverter()
Get the converter used to convert the items in the sequence
|
java.lang.String |
getExpressionName()
Get a name identifying the kind of expression, in terms meaningful to a user.
|
int |
getImplementationMethod()
An implementation of Expression must provide at least one of the methods evaluateItem(), iterate(), or process().
|
ItemType |
getItemType()
Determine the data type of the items returned by the expression, if possible
|
protected OperandRole |
getOperandRole()
Get the usage (in terms of streamability analysis) of the single operand
|
PlainType |
getRequiredItemType()
Get the required item type (the target type of the conversion
|
java.lang.String |
getStreamerName()
Get the (partial) name of a class that supports streaming of this kind of expression
|
SequenceIterator |
iterate(XPathContext context)
Iterate over the sequence of values
|
Expression |
optimize(ExpressionVisitor visitor,
ContextItemStaticInfo contextInfo)
Perform optimisation of an expression and its subexpressions.
|
void |
setConverter(Converter converter) |
Expression |
simplify()
Simplify an expression
|
Expression |
typeCheck(ExpressionVisitor visitor,
ContextItemStaticInfo contextInfo)
Type-check the expression
|
getBaseExpression, getOperand, operands, setBaseExpression, toShortString, toString
addToPathMap, adoptChildExpression, allowExtractingCommonSubexpressions, checkedOperands, checkForUpdatingSubexpressions, checkPermittedContents, computeDependencies, computeStaticProperties, dynamicError, effectiveBooleanValue, evaluateAsString, evaluatePendingUpdates, explain, getCardinality, getConfiguration, getConstructType, getCost, getDependencies, getEvaluationMethod, getExtraProperty, getIntegerBounds, getInterpretedExpression, getIntrinsicDependencies, getLocalRetainedStaticContext, getLocation, getNetCost, getObjectName, getPackageData, getParentExpression, getProperties, getProperty, getRetainedStaticContext, getScopingExpression, getSlotsUsed, getSpecialProperties, getStaticBaseURI, getStaticBaseURIString, getStaticType, getStaticUType, hasCompatibleStaticContext, hashCode, hasVariableBinding, identityHashCode, implementsStaticTypeCheck, isCallOn, isCallOnSystemFunction, isIdentical, isInstruction, isLiftable, isMultiThreaded, isSameExpression, isStaticPropertiesKnown, isSubtreeExpression, isUpdatingExpression, isVacuousExpression, markTailFunctionCalls, operandList, operandSparseList, optimizeChildren, process, resetLocalStaticProperties, restoreParentPointers, setEvaluationMethod, setExtraProperty, setFiltered, setFlattened, setLocation, setParentExpression, setRetainedStaticContext, setRetainedStaticContextLocally, setRetainedStaticContextThoroughly, setStaticProperty, simplifyChildren, staticTypeCheck, suppressValidation, toPattern, typeCheckChildren, typeError, unordered, verifyParentPointers, verifyParentPointers
public static AtomicSequenceConverter.ToStringMappingFunction TO_STRING_MAPPER
protected Converter converter
public AtomicSequenceConverter(Expression sequence, PlainType requiredItemType)
sequence
- this must be a sequence of atomic values. This is not checked; a ClassCastException
will occur if the precondition is not satisfied.requiredItemType
- the item type to which all items in the sequence should be converted,public Converter allocateConverter(Configuration config, boolean allowNull)
public Converter allocateConverter(Configuration config, boolean allowNull, ItemType sourceType)
protected OperandRole getOperandRole()
UnaryExpression
getOperandRole
in class UnaryExpression
public PlainType getRequiredItemType()
public Converter getConverter()
public void setConverter(Converter converter)
public Expression simplify() throws XPathException
simplify
in class Expression
XPathException
- if an error is discovered during expression
rewritingpublic Expression typeCheck(ExpressionVisitor visitor, ContextItemStaticInfo contextInfo) throws XPathException
typeCheck
in class UnaryExpression
visitor
- an expression visitorcontextInfo
- Information available statically about the context item: whether it is (possibly)
absent; its static type; its streaming posture.XPathException
- if an error is discovered during this phase
(typically a type error)public Expression optimize(ExpressionVisitor visitor, ContextItemStaticInfo contextInfo) throws XPathException
optimize
in class UnaryExpression
visitor
- an expression visitorcontextInfo
- 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 int getImplementationMethod()
getImplementationMethod
in class Expression
Expression.ITERATE_METHOD
or Expression.EVALUATE_METHOD
or
Expression.PROCESS_METHOD
public int computeSpecialProperties()
computeSpecialProperties
in class UnaryExpression
StaticProperty.NON_CREATIVE
.public java.lang.String getStreamerName()
Expression
getStreamerName
in class Expression
public Expression copy(RebindingMap rebindings)
copy
in class Expression
rebindings
- public SequenceIterator iterate(XPathContext context) throws XPathException
iterate
in class Expression
context
- supplies the context for evaluationXPathException
- if any dynamic error occurs evaluating the
expressionpublic AtomicValue 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 ItemType getItemType()
getItemType
in class UnaryExpression
public int computeCardinality()
computeCardinality
in class UnaryExpression
StaticProperty.ALLOWS_ZERO_OR_ONE
,
StaticProperty.EXACTLY_ONE
, StaticProperty.ALLOWS_ONE_OR_MORE
,
StaticProperty.ALLOWS_ZERO_OR_MORE
public boolean equals(java.lang.Object other)
equals
in class UnaryExpression
public int computeHashCode()
computeHashCode
in class UnaryExpression
public java.lang.String getExpressionName()
getExpressionName
in class Expression
protected java.lang.String displayOperator(Configuration config)
UnaryExpression
displayOperator
in class UnaryExpression
config
- the Saxon configurationpublic void export(ExpressionPresenter destination) throws XPathException
export
in interface ExportAgent
export
in class UnaryExpression
destination
- the expression presenter used to display the structureXPathException
- if the export fails, for example if an expression is found that won't work
in the target environment.Copyright (c) 2004-2018 Saxonica Limited. All rights reserved.