public class JavaExtensionFunctionCall extends FunctionCall implements Callable
Note that the binding of an XPath function call to a Java method is done in
class JavaExtensionLibrary
Modifier and Type | Class and Description |
---|---|
static class |
JavaExtensionFunctionCall.ConfigurationCheckingFunction
This class checks that NodeInfo objects returned by an extension function were created
under the right Configuration
|
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 |
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JavaExtensionFunctionCall()
Default constructor
|
Modifier and Type | Method and Description |
---|---|
PathMap.PathMapNodeSet |
addToPathMap(PathMap pathMap,
PathMap.PathMapNodeSet pathMapNodeSet)
Add a representation of this expression to a PathMap.
|
boolean |
adjustRequiredType(JavaExternalObjectType requiredType)
When a call to a Java extension function appears in a context where there the required type
is a Java external object (typically an xsl:variable with a declared type, or as an argument
to another Java extension function), notify this required type so that the process of converting
the result to an XDM value can be short-circuited.
|
static Sequence |
applyFunctionConversionRules(Sequence suppliedValue,
SequenceType requiredType,
StructuredQName functionName,
int argPosition,
XPathContext context)
Utility method available for use in called extension functions to check that
a supplied argument conforms to a required type, and perform conversion
using the function conversion rules if not
|
Sequence |
call(XPathContext context,
Sequence[] argValues)
Call an extension function previously identified using the bind() method.
|
int |
computeCardinality()
Compute the static cardinality of this expression
|
Expression |
copy(RebindingMap rebindings)
Copy an expression.
|
void |
export(ExpressionPresenter out)
Diagnostic print of expression structure.
|
PJConverter[] |
getArgumentConverters()
Get the converters used to convert the arguments from XPath values to Java values
|
java.lang.String |
getExpressionName()
Get a name identifying the kind of expression, in terms meaningful to a user.
|
protected java.lang.Object |
getField(java.lang.reflect.Field field,
java.lang.Object instance)
Access a field.
|
StructuredQName |
getFunctionName()
Get the qualified of the function being called
|
int |
getIntrinsicDependencies()
Determine which aspects of the context the expression depends on.
|
ItemType |
getItemType()
Determine the data type of the expression, if possible.
|
java.lang.Class[] |
getParameterTypes()
Get the types of the arguments
|
JPConverter |
getResultConverter()
Get the converter used to convert the result from a Java object to an XPath value
|
java.lang.Class |
getReturnClass()
Get the Java class of the value returned by the method
|
java.lang.Class |
getTargetClass()
Get the class containing the method being called
|
Function |
getTargetFunction(XPathContext context)
Get the target function to be called
|
java.lang.reflect.AccessibleObject |
getTargetMethod()
Get the target method (or field, or constructor) being called
|
void |
init(StructuredQName functionName,
java.lang.Class theClass,
java.lang.reflect.AccessibleObject object)
Initialization: creates an ExtensionFunctionCall
|
protected java.lang.Object |
invokeConstructor(java.lang.reflect.Constructor constructor,
java.lang.Object[] params)
Invoke a constructor.
|
protected java.lang.Object |
invokeMethod(java.lang.reflect.Method method,
java.lang.Object instance,
java.lang.Object[] params)
Invoke a method.
|
boolean |
isNodeCheckRequired()
Ask whether the result needs to be checked to ensure it contains no nodes from the wrong Configuration
|
boolean |
isReturnVoidAsThis() |
boolean |
isSubtreeExpression()
Determine whether the expression can be evaluated without reference to the part of the context
document outside the subtree rooted at the context node.
|
SequenceIterator |
iterate(XPathContext context)
Evaluate the function.
|
Expression |
preEvaluate(ExpressionVisitor visitor)
preEvaluate: this method suppresses compile-time evaluation by doing nothing
(because the external function might have side-effects and might use the context)
|
void |
prepareForDynamicCall(Configuration config) |
static java.lang.String |
toCamelCase(java.lang.String name,
boolean debug,
Logger diag)
Convert a name to camelCase (by removing hyphens and changing the following
letter to capitals)
|
Expression |
typeCheck(ExpressionVisitor visitor,
ContextItemStaticInfo contextInfo)
Type-check the expression.
|
addExternalFunctionCallToPathMap, checkArgumentCount, checkArguments, checkFunctionCall, computeHashCode, equals, evaluateArguments, getArg, getArguments, getArity, getDisplayName, getImplementationMethod, getNetCost, getOperanda, operands, optimize, pluralArguments, preEvaluateIfConstant, setArg, setArguments, setOperanda, setOperanda, simplifyArguments, toShortString, toString
adoptChildExpression, allowExtractingCommonSubexpressions, checkedOperands, checkForUpdatingSubexpressions, checkPermittedContents, computeDependencies, computeSpecialProperties, computeStaticProperties, dynamicError, effectiveBooleanValue, evaluateAsString, evaluateItem, evaluatePendingUpdates, explain, getCardinality, getConfiguration, getConstructType, getCost, getDependencies, getEvaluationMethod, getExtraProperty, getIntegerBounds, getInterpretedExpression, getLocalRetainedStaticContext, getLocation, getObjectName, getPackageData, getParentExpression, getProperties, getProperty, getRetainedStaticContext, getScopingExpression, getSlotsUsed, getSpecialProperties, getStaticBaseURI, getStaticBaseURIString, getStaticType, getStaticUType, getStreamerName, hasCompatibleStaticContext, hashCode, hasVariableBinding, identityHashCode, implementsStaticTypeCheck, isCallOn, isCallOnSystemFunction, isIdentical, isInstruction, isLiftable, isMultiThreaded, isSameExpression, isStaticPropertiesKnown, isUpdatingExpression, isVacuousExpression, markTailFunctionCalls, operandList, operandSparseList, optimizeChildren, process, resetLocalStaticProperties, restoreParentPointers, setEvaluationMethod, setExtraProperty, setFiltered, setFlattened, setLocation, setParentExpression, setRetainedStaticContext, setRetainedStaticContextLocally, setRetainedStaticContextThoroughly, setStaticProperty, simplify, simplifyChildren, staticTypeCheck, suppressValidation, toPattern, typeCheckChildren, typeError, unordered, verifyParentPointers, verifyParentPointers
public void init(StructuredQName functionName, java.lang.Class theClass, java.lang.reflect.AccessibleObject object)
functionName
- the name of the function, for display purposestheClass
- the Java class containing the method to be calledobject
- the method, field, or constructor of the Java class to be calledpublic java.lang.String getExpressionName()
getExpressionName
in class FunctionCall
public StructuredQName getFunctionName()
getFunctionName
in class FunctionCall
public Function getTargetFunction(XPathContext context) throws XPathException
getTargetFunction
in class FunctionCall
context
- the dynamic evaluation contextXPathException
- if the target function cannot be determinedpublic Expression preEvaluate(ExpressionVisitor visitor)
preEvaluate
in class FunctionCall
visitor
- an expression visitorpublic Expression typeCheck(ExpressionVisitor visitor, ContextItemStaticInfo contextInfo) throws XPathException
FunctionCall
typeCheck
in class FunctionCall
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 void prepareForDynamicCall(Configuration config) throws XPathException
XPathException
public boolean adjustRequiredType(JavaExternalObjectType requiredType) throws XPathException
adjustRequiredType
in class FunctionCall
requiredType
- the required type of the result of the function, determined by the context
in which the function call appearsXPathException
- if the required return type is incompatible with the type actually returned
by the Java methodpublic Expression copy(RebindingMap rebindings)
copy
in class Expression
rebindings
- public int getIntrinsicDependencies()
getIntrinsicDependencies
in class Expression
public boolean isSubtreeExpression()
isSubtreeExpression
in class Expression
public PathMap.PathMapNodeSet addToPathMap(PathMap pathMap, PathMap.PathMapNodeSet pathMapNodeSet)
The default implementation of this method assumes that an expression does no navigation other than the navigation done by evaluating its subexpressions, and that the subexpressions are evaluated in the same context as the containing expression. The method must be overridden for any expression where these assumptions do not hold. For example, implementations exist for AxisExpression, ParentExpression, and RootExpression (because they perform navigation), and for the doc(), document(), and collection() functions because they create a new navigation root. Implementations also exist for PathExpression and FilterExpression because they have subexpressions that are evaluated in a different context from the calling expression.
addToPathMap
in class Expression
pathMap
- the PathMap to which the expression should be addedpathMapNodeSet
- the PathMapNodeSet to which the paths embodied in this expression should be addedpublic boolean isNodeCheckRequired()
public SequenceIterator iterate(XPathContext context) throws XPathException
iterate
in class FunctionCall
context
- The context in which the function is to be evaluatedXPathException
- if the function cannot be evaluated.public java.lang.Class getTargetClass()
public java.lang.reflect.AccessibleObject getTargetMethod()
public java.lang.Class[] getParameterTypes()
public Sequence call(XPathContext context, Sequence[] argValues) throws XPathException
call
in interface Callable
context
- The XPath dynamic evaluation contextargValues
- The values of the argumentsXPathException
- if a dynamic error occurs during the evaluation of the expressionpublic ItemType getItemType()
This method will always return a result, though it may be the best approximation that is available at the time.
getItemType
in class Expression
public int computeCardinality()
Expression
computeCardinality
in class Expression
StaticProperty.ALLOWS_ZERO_OR_ONE
,
StaticProperty.EXACTLY_ONE
, StaticProperty.ALLOWS_ONE_OR_MORE
,
StaticProperty.ALLOWS_ZERO_OR_MORE
public java.lang.Class getReturnClass()
public PJConverter[] getArgumentConverters()
public JPConverter getResultConverter()
protected java.lang.Object invokeConstructor(java.lang.reflect.Constructor constructor, java.lang.Object[] params) throws java.lang.InstantiationException, java.lang.IllegalAccessException, java.lang.reflect.InvocationTargetException
constructor
- The constructor to be invokedparams
- The parameters to be passed to the constructorjava.lang.InstantiationException
- if the invocation throws an InstantiationExceptionjava.lang.IllegalAccessException
- if the invocation throws an IllegalAccessExceptionjava.lang.reflect.InvocationTargetException
- if the invocation throws an InvocationTargetException (which happens
when the constructor itself throws an exception)protected java.lang.Object invokeMethod(java.lang.reflect.Method method, java.lang.Object instance, java.lang.Object[] params) throws java.lang.IllegalAccessException, java.lang.reflect.InvocationTargetException
method
- The method to be invokedinstance
- The object on which the method is to be invoked. This is set to null if the
method is static.params
- The parameters to be passed to the methodjava.lang.IllegalAccessException
- if the invocation throws an IllegalAccessExceptionjava.lang.reflect.InvocationTargetException
- if the invocation throws an InvocationTargetException (which happens
when the method itself throws an exception)protected java.lang.Object getField(java.lang.reflect.Field field, java.lang.Object instance) throws java.lang.IllegalAccessException
field
- The field to be retrievedinstance
- The object whose field is to be retrieved. This is set to null if the
field is static.java.lang.IllegalAccessException
- if the invocation throws an IllegalAccessExceptionpublic static Sequence applyFunctionConversionRules(Sequence suppliedValue, SequenceType requiredType, StructuredQName functionName, int argPosition, XPathContext context) throws XPathException
suppliedValue
- the value supplied by the callerrequiredType
- the type required for the argumentfunctionName
- the name of the function (for diagnostics)argPosition
- the ordinal position of the argument being checked in the XPath function call,
starting at 0 for the first argumentcontext
- the XPath dynamic contextXPathException
- if type checking failspublic static java.lang.String toCamelCase(java.lang.String name, boolean debug, Logger diag)
name
- the name to be converted to camelCasedebug
- true if tracing is requireddiag
- the output stream for diagnostic trace outputpublic boolean isReturnVoidAsThis()
public void export(ExpressionPresenter out) throws XPathException
export
in interface ExportAgent
export
in class FunctionCall
out
- the destination of the outputXPathException
- 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.