com.saxonica.config

Class JavaExtensionLibrary.UnresolvedExtensionFunctionCall

java.lang.Object

net.sf.saxon.expr.Expression

net.sf.saxon.expr.FunctionCall

com.saxonica.config.JavaExtensionLibrary.UnresolvedExtensionFunctionCall

All Implemented Interfaces:

Callable, ExportAgent, Locatable, IdentityComparable

Enclosing class:

JavaExtensionLibrary

public class JavaExtensionLibrary.UnresolvedExtensionFunctionCall
extends FunctionCall
implements Callable

Inner class representing an unresolved extension function call. This arises when there is insufficient static type information available at the time the function call is parsed to determine which of several candidate Java methods to invoke. The function call cannot be executed; it must be resolved to an actual Java method during the analysis phase.

Field Summary

Fields inherited from class net.sf.saxon.expr.Expression

EFFECTIVE_BOOLEAN_VALUE, EVALUATE_METHOD, ITEM_FEED_METHOD, ITERATE_METHOD, MAX_COST, MAX_SEQUENCE_LENGTH, MAX_STRING_LENGTH, PROCESS_METHOD, staticProperties, UNBOUNDED_LOWER, UNBOUNDED_UPPER, UPDATE_METHOD, WATCH_METHOD

Constructor Summary

Constructors

Constructor and Description
UnresolvedExtensionFunctionCall(StructuredQName functionName, java.lang.Class theClass, java.util.List<java.lang.reflect.AccessibleObject> candidateMethods, Expression[] staticArgs, Configuration config, boolean debug)

Method Summary

Modifier and Type	Method and Description
Sequence<?>	call(XPathContext context, Sequence[] arguments) Evaluate the expression
protected int	computeCardinality() Compute the static cardinality of this expression
Expression	copy(RebindingMap rebindings) Copy an expression.
StructuredQName	getFunctionName() Get the qualified of the function being called
ItemType	getItemType() Determine the data type of the expression, if possible.
Function	getTargetFunction(XPathContext context) Get the target function to be called
Expression	resolve(SequenceType[] argTypes)
Expression	typeCheck(ExpressionVisitor visitor, ContextItemStaticInfo contextInfo) Type-check the expression.

Methods inherited from class net.sf.saxon.expr.FunctionCall

addExternalFunctionCallToPathMap, adjustRequiredType, checkArgumentCount, checkArguments, checkFunctionCall, computeHashCode, equals, evaluateArguments, export, getArg, getArguments, getArity, getDisplayName, getExpressionName, getImplementationMethod, getNetCost, getOperanda, iterate, operands, optimize, pluralArguments, preEvaluate, preEvaluateIfConstant, setArg, setArguments, setOperanda, setOperanda, simplifyArguments, toShortString, toString

Methods inherited from class net.sf.saxon.expr.Expression

addToPathMap, adoptChildExpression, allowExtractingCommonSubexpressions, checkedOperands, checkForUpdatingSubexpressions, checkPermittedContents, computeDependencies, computeSpecialProperties, computeStaticProperties, dynamicError, effectiveBooleanValue, evaluateAsString, evaluateItem, evaluatePendingUpdates, explain, getCardinality, getConfiguration, getConstructType, getCost, getDependencies, getEvaluationMethod, getExtraProperty, getIntegerBounds, getInterpretedExpression, getIntrinsicDependencies, getLocalRetainedStaticContext, getLocation, getObjectName, getPackageData, getParentExpression, getProperties, getProperty, getRetainedStaticContext, getScopingExpression, getSlotsUsed, getSpecialProperties, getStaticBaseURI, getStaticBaseURIString, getStaticType, getStaticUType, getStreamerName, hasCompatibleStaticContext, hashCode, hasSpecialProperty, hasVariableBinding, identityHashCode, implementsStaticTypeCheck, isCallOn, isEqual, isIdentical, isInstruction, isLiftable, isMultiThreaded, isStaticPropertiesKnown, isSubtreeExpression, isUpdatingExpression, isVacuousExpression, markTailFunctionCalls, operandList, operandSparseList, optimizeChildren, prepareForStreaming, process, resetLocalStaticProperties, restoreParentPointers, setEvaluationMethod, setExtraProperty, setFiltered, setFlattened, setLocation, setParentExpression, setRetainedStaticContext, setRetainedStaticContextLocally, setRetainedStaticContextThoroughly, setStaticProperty, simplify, simplifyChildren, staticTypeCheck, suppressValidation, toPattern, typeCheckChildren, typeError, unordered, verifyParentPointers

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

UnresolvedExtensionFunctionCall

public UnresolvedExtensionFunctionCall(StructuredQName functionName,
                                       java.lang.Class theClass,
                                       java.util.List<java.lang.reflect.AccessibleObject> candidateMethods,
                                       Expression[] staticArgs,
                                       Configuration config,
                                       boolean debug)

Method Detail

getFunctionName

public StructuredQName getFunctionName()

Get the qualified of the function being called

Specified by:

getFunctionName in class FunctionCall

Returns:

the qualified name

typeCheck

public Expression typeCheck(ExpressionVisitor visitor,
                            ContextItemStaticInfo contextInfo)
                     throws XPathException

Type-check the expression.

Overrides:

typeCheck in class FunctionCall

Parameters:

visitor - an expression visitor

contextInfo - Information available statically about the context item: whether it is (possibly) absent; its static type; its streaming posture.

Returns:

the original expression, rewritten to perform necessary run-time type checks, and to perform other type-related optimizations

Throws:

XPathException - if an error is discovered during this phase (typically a type error)

resolve

public Expression resolve(SequenceType[] argTypes)
                   throws XPathException

Throws:

XPathException

call

public Sequence<?> call(XPathContext context,
                        Sequence[] arguments)
                 throws XPathException

Evaluate the expression

Specified by:

call in interface Callable

Parameters:

context - the dynamic evaluation context

arguments - the values of the arguments, supplied as Sequences

Returns:

the result of the evaluation, in the form of a Sequence

Throws:

XPathException - if a dynamic error occurs during the evaluation of the expression

getTargetFunction

public Function getTargetFunction(XPathContext context)

Get the target function to be called

Specified by:

getTargetFunction in class FunctionCall

Parameters:

context - the dynamic evaluation context

Returns:

the target function

getItemType

public ItemType getItemType()

Determine the data type of the expression, if possible. All expression return sequences, in general; this method determines the type of the items within the sequence, assuming that (a) this is known in advance, and (b) it is the same for all items in the sequence.

This method should always return a result, though it may be the best approximation that is available at the time.

Specified by:

getItemType in class Expression

Returns:

a value such as Type.STRING, Type.BOOLEAN, Type.NUMBER, Type.NODE, or Type.ITEM (meaning not known at compile time)

computeCardinality

protected int computeCardinality()

Compute the static cardinality of this expression

Specified by:

computeCardinality in class Expression

Returns:

the computed cardinality, as one of the values StaticProperty.ALLOWS_ZERO_OR_ONE, StaticProperty.EXACTLY_ONE, StaticProperty.ALLOWS_ONE_OR_MORE, StaticProperty.ALLOWS_ZERO_OR_MORE

copy

public Expression copy(RebindingMap rebindings)

Copy an expression. This makes a deep copy.

Specified by:

copy in class Expression

Parameters:

rebindings - variables to be re-bound

Returns:

the copy of the original expression