java.lang.Object
- net.sf.saxon.query.XQueryFunction

All Implemented Interfaces:

javax.xml.transform.SourceLocator, FunctionDefinition, Declaration, Location, org.xml.sax.Locator
```
public class XQueryFunction
extends java.lang.Object
implements Declaration, Location, FunctionDefinition
```
A user-defined function in an XQuery module

Constructor Summary

Constructors
Constructor Description

XQueryFunction()
Create an XQuery function

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`addParameter(UserFunctionParameter param)`	Add an argument to the list of parameters
`void`	`checkReferences(ExpressionVisitor visitor)`	Type-check references to this function
`void`	`compile()`	Compile this function to create a run-time definition that can be interpreted (note, this has nothing to do with Java code generation)
`void`	`explain(ExpressionPresenter out)`	Produce diagnostic output showing the compiled and optimized expression tree for a function
`void`	`fixupReferences()`	Fix up references to this function
`AnnotationList`	`getAnnotations()`	Get the annotations defined on this function
`SequenceType[]`	`getArgumentTypes()`	Get the declared types of the arguments of this function
`Expression`	`getBody()`	Get the body of the function
`int`	`getColumnNumber()`	Return the column number
`Expression`	`getDefaultValueExpression(int i)`	Get the default value expression of the Nth parameter, if any
`java.lang.String`	`getDisplayName()`	Get the name of the function for display in error messages
`StructuredQName`	`getFunctionName()`	Get the name of the function as a structured QName
`HostLanguage`	`getHostLanguage()`	Get the host language (XSLT, XQuery, XPath) used to implement the code in this container
`SymbolicName`	`getIdentificationKey()`	Get an identifying key for this function, which incorporates the URI and local part of the function name plus the arity
`static SymbolicName`	`getIdentificationKey(StructuredQName qName, int arity)`	Construct what the identification key would be for a function with given URI, local name, and arity
`int`	`getLineNumber()`	Get the line number of the instruction in the source stylesheet module.
`int`	`getMinimumArity()`	Get the minimum arity of the function
`NamespaceResolver`	`getNamespaceResolver()`	Get the namespace context of the instruction.
`int`	`getNumberOfParameters()`	Get the maximum arity of the function
`StructuredQName`	`getObjectName()`	Get a name identifying the object of the expression, for example a function name, template name, variable name, key name, element name, etc.
`PackageData`	`getPackageData()`	Get data about the unit of compilation (XQuery module, XSLT package) to which this container belongs
`UserFunctionParameter[]`	`getParameterDefinitions()`	Get the definitions of the arguments to this function
`StructuredQName`	`getParameterName(int i)`	Get the name of the Nth parameter, if any
`int`	`getPositionOfParameter(StructuredQName name)`	Get the position in the parameter list of a given parameter name
`java.util.Iterator<java.lang.String>`	`getProperties()`	Get an iterator over all the properties available.
`java.lang.Object`	`getProperty(java.lang.String name)`	Get the value of a particular property of the instruction.
`java.lang.String`	`getPublicId()`	Return the public identifier for the current document event.
`SequenceType`	`getResultType()`	Get the result type of the function
`StaticContext`	`getStaticContext()`	Get the static context for this function
`java.lang.String`	`getSystemId()`	Get the system identifier (URI) of the source module containing the instruction.
`UserFunction`	`getUserFunction()`	Get the callable compiled function contained within this XQueryFunction definition.
`boolean`	`hasAnnotation(StructuredQName name)`	Ask whether the function has an annotation with a particular name
`boolean`	`isMemoFunction()`	Find out whether this is a memo function
`boolean`	`isPrivate()`	Ask whether this is a private function (as defined in XQuery 3.0)
`boolean`	`isUpdating()`	Ask whether this is an updating function (as defined in XQuery Update)
`void`	`optimize()`	Optimize the body of this function
`void`	`registerReference(UserFunctionResolvable ufc)`	Register a call on this function
`Location`	`saveLocation()`	Get an immutable copy of this Location object.
`void`	`setAnnotations(AnnotationList annotations)`	Set the annotations on this function
`void`	`setBody(Expression body)`	Set the body of the function
`void`	`setFunctionName(StructuredQName name)`	Set the name of the function
`void`	`setLocation(Location location)`	Set the location of the source declaration of the function
`void`	`setMemoFunction(boolean isMemoFunction)`	Set that this is, or is not, a memo function.
`void`	`setResultType(SequenceType resultType)`	Set the required result type of the function
`void`	`setStaticContext(QueryModule env)`	Set the static context for this function
`void`	`setUpdating(boolean isUpdating)`	Set whether this is an updating function (as defined in XQuery Update)

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - XQueryFunction
```
public XQueryFunction()
```
    Create an XQuery function
- Method Detail
  - getPackageData
```
public PackageData getPackageData()
```
    Get data about the unit of compilation (XQuery module, XSLT package) to which this container belongs
    
    Returns:
    
    the package information
  - setFunctionName
```
public void setFunctionName(StructuredQName name)
```
    Set the name of the function
    
    Parameters:
    
    name - the name of the function as a StructuredQName object
  - addParameter
```
public void addParameter(UserFunctionParameter param)
```
    Add an argument to the list of parameters
    
    Parameters:
    
    param - the formal declaration of the parameter to be added
  - setResultType
```
public void setResultType(SequenceType resultType)
```
    Set the required result type of the function
    
    Parameters:
    
    resultType - the declared result type of the function
  - setBody
```
public void setBody(Expression body)
```
    Set the body of the function
    
    Parameters:
    
    body - the expression forming the body of the function
  - getBody
```
public Expression getBody()
```
    Get the body of the function
    
    Returns:
    
    the expression making up the body of the function
  - setLocation
```
public void setLocation(Location location)
```
    Set the location of the source declaration of the function
    
    Parameters:
    
    location - the source location
  - getFunctionName
```
public StructuredQName getFunctionName()
```
    Get the name of the function as a structured QName
    
    Specified by:
    
    getFunctionName in interface FunctionDefinition
    
    Returns:
    
    the name of the function as a structured QName
  - getDisplayName
```
public java.lang.String getDisplayName()
```
    Get the name of the function for display in error messages
    
    Returns:
    
    the name of the function as a lexical QName
  - getIdentificationKey
```
public SymbolicName getIdentificationKey()
```
    Get an identifying key for this function, which incorporates the URI and local part of the function name plus the arity
    
    Returns:
    
    an identifying key
  - getIdentificationKey
```
public static SymbolicName getIdentificationKey(StructuredQName qName,
                                                int arity)
```
    Construct what the identification key would be for a function with given URI, local name, and arity
    
    Parameters:
    
    qName - the name of the function
    
    arity - the number of arguments
    
    Returns:
    
    an identifying key
  - getResultType
```
public SequenceType getResultType()
```
    Get the result type of the function
    
    Returns:
    
    the declared result type
  - setStaticContext
```
public void setStaticContext(QueryModule env)
```
    Set the static context for this function
    
    Parameters:
    
    env - the static context for the module in which the function is declared
  - getStaticContext
```
public StaticContext getStaticContext()
```
    Get the static context for this function
    
    Returns:
    
    the static context for the module in which the function is declared
  - getArgumentTypes
```
public SequenceType[] getArgumentTypes()
```
    Get the declared types of the arguments of this function
    
    Returns:
    
    an array, holding the types of the arguments in order
  - getParameterDefinitions
```
public UserFunctionParameter[] getParameterDefinitions()
```
    Get the definitions of the arguments to this function
    
    Returns:
    
    an array of UserFunctionParameter objects, one for each argument
  - getPositionOfParameter
```
public int getPositionOfParameter(StructuredQName name)
```
    Get the position in the parameter list of a given parameter name
    
    Specified by:
    
    getPositionOfParameter in interface FunctionDefinition
    
    Parameters:
    
    name - the name of the required parameter
    
    Returns:
    
    the position of the parameter in the parameter list, or -1 if absent
  - getParameterName
```
public StructuredQName getParameterName(int i)
```
    Get the name of the Nth parameter, if any
    
    Specified by:
    
    getParameterName in interface FunctionDefinition
    
    Parameters:
    
    i - the position of the required parameter
    
    Returns:
    
    the name (keyword) of the Nth parameter
  - getDefaultValueExpression
```
public Expression getDefaultValueExpression(int i)
```
    Get the default value expression of the Nth parameter, if any
    
    Specified by:
    
    getDefaultValueExpression in interface FunctionDefinition
    
    Parameters:
    
    i - the position of the required parameter
    
    Returns:
    
    the expression for computing the value of the Nth parameter, or null if there is none
  - getNumberOfParameters
```
public int getNumberOfParameters()
```
    Get the maximum arity of the function
    
    Specified by:
    
    getNumberOfParameters in interface FunctionDefinition
    
    Returns:
    
    the arity (the maximum number of arguments including optional arguments)
  - getMinimumArity
```
public int getMinimumArity()
```
    Get the minimum arity of the function
    
    Specified by:
    
    getMinimumArity in interface FunctionDefinition
    
    Returns:
    
    the number of mandatory parameters
  - registerReference
```
public void registerReference(UserFunctionResolvable ufc)
```
    Register a call on this function
    
    Parameters:
    
    ufc - a user function call that references this function.
  - setMemoFunction
```
public void setMemoFunction(boolean isMemoFunction)
```
    Set that this is, or is not, a memo function. A memo function remembers the results of calls on the function so that the a subsequent call with the same arguments simply look up the result
    
    Parameters:
    
    isMemoFunction - true if this is a memo function.
  - isMemoFunction
```
public boolean isMemoFunction()
```
    Find out whether this is a memo function
    
    Returns:
    
    true if this is a memo function
  - setUpdating
```
public void setUpdating(boolean isUpdating)
```
    Set whether this is an updating function (as defined in XQuery Update)
    
    Parameters:
    
    isUpdating - true if this is an updating function
  - isUpdating
```
public boolean isUpdating()
```
    Ask whether this is an updating function (as defined in XQuery Update)
    
    Returns:
    
    true if this is an updating function
  - setAnnotations
```
public void setAnnotations(AnnotationList annotations)
```
    Set the annotations on this function
    
    Parameters:
    
    annotations - the annotations, indexed by annotation name
  - getAnnotations
```
public AnnotationList getAnnotations()
```
    Get the annotations defined on this function
    
    Returns:
    
    the list of annotations defined on this function
  - hasAnnotation
```
public boolean hasAnnotation(StructuredQName name)
```
    Ask whether the function has an annotation with a particular name
    
    Parameters:
    
    name - the name of the required annotation
    
    Returns:
    
    true if the function has an annotation with this name
  - isPrivate
```
public boolean isPrivate()
```
    Ask whether this is a private function (as defined in XQuery 3.0)
    
    Returns:
    
    true if this is a private function
  - compile
```
public void compile()
             throws XPathException
```
    Compile this function to create a run-time definition that can be interpreted (note, this has nothing to do with Java code generation)
    
    Throws:
    
    XPathException - if errors are found
  - optimize
```
public void optimize()
              throws XPathException
```
    Optimize the body of this function
    
    Throws:
    
    XPathException - if execution fails, for example because the function is updating and contains constructs not allowed in an updating function, or vice-versa.
  - fixupReferences
```
public void fixupReferences()
```
    Fix up references to this function
  - checkReferences
```
public void checkReferences(ExpressionVisitor visitor)
                     throws XPathException
```
    Type-check references to this function
    
    Parameters:
    
    visitor - the expression visitor
    
    Throws:
    
    XPathException - if type errors are found
  - explain
```
public void explain(ExpressionPresenter out)
             throws XPathException
```
    Produce diagnostic output showing the compiled and optimized expression tree for a function
    
    Parameters:
    
    out - the destination to be used
    
    Throws:
    
    XPathException - if things go wrong
  - getUserFunction
```
public UserFunction getUserFunction()
```
    Get the callable compiled function contained within this XQueryFunction definition.
    
    Returns:
    
    the compiled function object
  - getObjectName
```
public StructuredQName getObjectName()
```
    Get a name identifying the object of the expression, for example a function name, template name, variable name, key name, element name, etc. This is used only where the name is known statically.
    
    Returns:
    
    the function name
  - getSystemId
```
public java.lang.String getSystemId()
```
    Get the system identifier (URI) of the source module containing the instruction. This will generally be an absolute URI. If the system identifier is not known, the method may return null. In some cases, for example where XML external entities are used, the correct system identifier is not always retained.
    
    Specified by:
    
    getSystemId in interface Location
    
    Specified by:
    
    getSystemId in interface org.xml.sax.Locator
    
    Specified by:
    
    getSystemId in interface javax.xml.transform.SourceLocator
    
    Returns:
    
    the system ID, or null if the information is not available.
  - getLineNumber
```
public int getLineNumber()
```
    Get the line number of the instruction in the source stylesheet module. If this is not known, or if the instruction is an artificial one that does not relate to anything in the source code, the value returned may be -1.
    
    Specified by:
    
    getLineNumber in interface Location
    
    Specified by:
    
    getLineNumber in interface org.xml.sax.Locator
    
    Specified by:
    
    getLineNumber in interface javax.xml.transform.SourceLocator
    
    Returns:
    
    the line number, or -1 if the information is not available.
  - getPublicId
```
public java.lang.String getPublicId()
```
    Return the public identifier for the current document event.
    
    Specified by:
    
    getPublicId in interface Location
    
    Specified by:
    
    getPublicId in interface org.xml.sax.Locator
    
    Specified by:
    
    getPublicId in interface javax.xml.transform.SourceLocator
    
    Returns:
    
    A string containing the public identifier, or null if none is available.
    
    See Also:
    
    getSystemId()
  - getColumnNumber
```
public int getColumnNumber()
```
    Return the column number
    
    Specified by:
    
    getColumnNumber in interface Location
    
    Specified by:
    
    getColumnNumber in interface org.xml.sax.Locator
    
    Specified by:
    
    getColumnNumber in interface javax.xml.transform.SourceLocator
    
    Returns:
    
    The column number, or -1 if none is available.
    
    See Also:
    
    getLineNumber()
  - saveLocation
```
public Location saveLocation()
```
    Get an immutable copy of this Location object. By default Location objects may be mutable, so they should not be saved for later use. The result of this operation holds the same location information, but in an immutable form.
    
    Specified by:
    
    saveLocation in interface Location
    
    Returns:
    
    an immutable copy (which may be the original object, if it is already immutable)
  - getNamespaceResolver
```
public NamespaceResolver getNamespaceResolver()
```
    Get the namespace context of the instruction. This will not always be available, in which case the method returns null.
    
    Returns:
    
    a resolver representing the namespace context for the function
  - getProperty
```
public java.lang.Object getProperty(java.lang.String name)
```
    Get the value of a particular property of the instruction. Properties of XSLT instructions are generally known by the name of the stylesheet attribute that defines them.
    
    Parameters:
    
    name - The name of the required property
    
    Returns:
    
    The value of the requested property, or null if the property is not available
  - getProperties
```
public java.util.Iterator<java.lang.String> getProperties()
```
    Get an iterator over all the properties available. The values returned by the iterator will be of type String, and each string can be supplied as input to the getProperty() method to retrieve the value of the property.
    
    Returns:
    
    the properties available
  - getHostLanguage
```
public HostLanguage getHostLanguage()
```
    Get the host language (XSLT, XQuery, XPath) used to implement the code in this container
    
    Returns:
    
    HostLanguage.XQUERY

Class XQueryFunction

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

XQueryFunction

Method Detail

getPackageData

setFunctionName

addParameter

setResultType

setBody

getBody

setLocation

getFunctionName

getDisplayName

getIdentificationKey

getIdentificationKey

getResultType

setStaticContext

getStaticContext

getArgumentTypes

getParameterDefinitions

getPositionOfParameter

getParameterName

getDefaultValueExpression

getNumberOfParameters

getMinimumArity

registerReference

setMemoFunction

isMemoFunction

setUpdating

isUpdating

setAnnotations

getAnnotations

hasAnnotation

isPrivate

compile

optimize

fixupReferences

checkReferences

explain

getUserFunction

getObjectName

getSystemId

getLineNumber

getPublicId

getColumnNumber

saveLocation

getNamespaceResolver

getProperty

getProperties

getHostLanguage