net.sf.saxon.query

Class XQueryFunction

Implemented Interfaces:
InstructionInfo, Locator, Container, Declaration, LocationProvider, SaxonLocator, Serializable, SourceLocator

public class XQueryFunction
extends java.lang.Object
implements InstructionInfo, Container, Declaration

Constructor Summary

XQueryFunction()
Create an XQuery function

Method Summary

protected void
addArgument(UserFunctionParameter argument)
Add an argument to the list of arguments
void
checkReferences(ExpressionVisitor visitor)
Type-check references to this function
UserFunction
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(StaticContext env)
Fix up references to 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
int
getConstructType()
Get the type of construct.
String
getDisplayName()
Get the name of the function for display in error messages
Executable
getExecutable()
Get the executable in which this function is contained
StructuredQName
getFunctionName()
Get the name of the function as a structured QName
int
getHostLanguage()
Get the host language (XSLT, XQuery, XPath) used to implement the code in this container
String
getIdentificationKey()
Get an identifying key for this function, which incorporates the URI and local part of the function name plus the arity
static String
getIdentificationKey(String uri, String localName, int arity)
Construct what the identification key would be for a function with given URI, local name, and arity
static String
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
getLineNumber(long locationId)
LocationProvider
getLocationProvider()
Get the LocationProvider allowing location identifiers to be resolved.
NamespaceResolver
getNamespaceResolver()
Get the namespace context of the instruction.
int
getNumberOfArguments()
Get the arity of the function
StructuredQName
getObjectName(NamePool pool)
Get a name identifying the object of the expression, for example a function name, template name, variable name, key name, element name, etc.
UserFunctionParameter[]
getParameterDefinitions()
Get the definitions of the arguments to this function
Iterator
getProperties()
Get an iterator over all the properties available.
Object
getProperty(String name)
Get the value of a particular property of the instruction.
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
String
getSystemId()
Get the system identifier (URI) of the source module containing the instruction.
String
getSystemId(long locationId)
UserFunction
getUserFunction()
Get the callable compiled function contained within this XQueryFunction definition.
boolean
isMemoFunction()
Find out whether this is a memo function
void
optimize()
Optimize the body of this function
void
registerReference(UserFunctionCall ufc)
Register a call on this function
boolean
replaceSubExpression(Expression original, Expression replacement)
Replace one subexpression by a replacement subexpression
protected void
setBody(Expression body)
Set the body of the function
protected void
setColumnNumber(int column)
Set the column number of the function declaration
void
setExecutable(Executable exec)
Set the executable in which this function is contained
protected void
setFunctionName(StructuredQName name)
Set the name of the function
protected void
setLineNumber(int line)
Set the line number of the function declaration within its module
void
setMemoFunction(boolean isMemoFunction)
Set that this is, or is not, a memo function.
protected void
setResultType(SequenceType resultType)
Set the required result type of the function
void
setStaticContext(StaticContext env)
Set the static context for this function
protected void
setSystemId(String systemId)
Set the system ID of the module containing the function

Constructor Details

XQueryFunction

public XQueryFunction()
Create an XQuery function

Method Details

addArgument

protected void addArgument(UserFunctionParameter argument)
Add an argument to the list of arguments
Parameters:
argument - the formal declaration of the argument to be added

checkReferences

public void checkReferences(ExpressionVisitor visitor)
            throws XPathException
Type-check references to this function
Parameters:
visitor - the expression visitor

compile

public UserFunction 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)
Returns:
the compiled UserFunction object
Throws:
XPathException - if errors are found

explain

public void explain(ExpressionPresenter out)
Produce diagnostic output showing the compiled and optimized expression tree for a function
Parameters:
out - the destination to be used

fixupReferences

public void fixupReferences(StaticContext env)
            throws XPathException
Fix up references to this function
Parameters:
env - the static context

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

getBody

public Expression getBody()
Get the body of the function
Returns:
the expression making up the body of the function

getColumnNumber

public int getColumnNumber()
Return the column number
Returns:
The column number, or -1 if none is available.
See Also:
getLineNumber

getConstructType

public int getConstructType()
Specified by:
getConstructType in interface InstructionInfo

getDisplayName

public String getDisplayName()
Get the name of the function for display in error messages
Returns:
the name of the function as a lexical QName

getExecutable

public Executable getExecutable()
Get the executable in which this function is contained
Specified by:
getExecutable in interface Container
Returns:
the executable

getFunctionName

public StructuredQName getFunctionName()
Get the name of the function as a structured QName
Returns:
the name of the function as a structured QName

getHostLanguage

public int getHostLanguage()
Get the host language (XSLT, XQuery, XPath) used to implement the code in this container
Specified by:
getHostLanguage in interface Container

getIdentificationKey

public String 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 String getIdentificationKey(String uri,
                                          String localName,
                                          int arity)
Construct what the identification key would be for a function with given URI, local name, and arity
Parameters:
uri - the URI part of the function name
localName - the local part of the function name
arity - the number of arguments in the function
Returns:
an identifying key

getIdentificationKey

public static String 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

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 InstructionInfo

getLineNumber

public int getLineNumber(long locationId)
Specified by:
getLineNumber in interface LocationProvider

getLocationProvider

public LocationProvider getLocationProvider()
Get the LocationProvider allowing location identifiers to be resolved.
Specified by:
getLocationProvider in interface Container
Returns:
the location provider

getNamespaceResolver

public NamespaceResolver getNamespaceResolver()
Get the namespace context of the instruction. This will not always be available, in which case the method returns null.
Specified by:
getNamespaceResolver in interface InstructionInfo

getNumberOfArguments

public int getNumberOfArguments()
Get the arity of the function
Returns:
the arity (the number of arguments)

getObjectName

public StructuredQName getObjectName(NamePool pool)
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.
Specified by:
getObjectName in interface InstructionInfo
Parameters:
pool - the name pool (not used in this implementation)

getParameterDefinitions

public UserFunctionParameter[] getParameterDefinitions()
Get the definitions of the arguments to this function
Returns:
an array of UserFunctionParameter objects, one for each argument

getProperties

public Iterator 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.
Specified by:
getProperties in interface InstructionInfo

getProperty

public Object getProperty(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.
Specified by:
getProperty in interface InstructionInfo
Parameters:
name - The name of the required property
Returns:
The value of the requested property, or null if the property is not available

getPublicId

public String getPublicId()
Return the public identifier for the current document event.
Returns:
A string containing the public identifier, or null if none is available.
See Also:
getSystemId

getResultType

public SequenceType getResultType()
Get the result type of the function
Returns:
the declared result type

getStaticContext

public StaticContext getStaticContext()
Get the static context for this function
Returns:
the static context for the module in which the function is declared

getSystemId

public 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 InstructionInfo

getSystemId

public String getSystemId(long locationId)
Specified by:
getSystemId in interface LocationProvider

getUserFunction

public UserFunction getUserFunction()
Get the callable compiled function contained within this XQueryFunction definition.
Returns:
the compiled function object

isMemoFunction

public boolean isMemoFunction()
Find out whether this is a memo function
Returns:
true if this is a memo function

optimize

public void optimize()
            throws XPathException
Optimize the body of this function

registerReference

public void registerReference(UserFunctionCall ufc)
Register a call on this function
Parameters:
ufc - a user function call that references this function.

replaceSubExpression

public boolean replaceSubExpression(Expression original,
                                    Expression replacement)
Replace one subexpression by a replacement subexpression
Specified by:
replaceSubExpression in interface Container
Parameters:
original - the original subexpression
replacement - the replacement subexpression
Returns:
true if the original subexpression is found

setBody

protected void setBody(Expression body)
Set the body of the function
Parameters:
body - the expression forming the body of the function

setColumnNumber

protected void setColumnNumber(int column)
Set the column number of the function declaration
Parameters:
column - the column number of the function declaration

setExecutable

public void setExecutable(Executable exec)
Set the executable in which this function is contained
Parameters:
exec - the executable

setFunctionName

protected void setFunctionName(StructuredQName name)
Set the name of the function
Parameters:
name - the name of the function as a StructuredQName object

setLineNumber

protected void setLineNumber(int line)
Set the line number of the function declaration within its module
Parameters:
line - the line number of the function declaration

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.

setResultType

protected void setResultType(SequenceType resultType)
Set the required result type of the function
Parameters:
resultType - the declared result type of the function

setStaticContext

public void setStaticContext(StaticContext env)
Set the static context for this function
Parameters:
env - the static context for the module in which the function is declared

setSystemId

protected void setSystemId(String systemId)
Set the system ID of the module containing the function
Parameters:
systemId - the system ID (= base URI) of the module containing the function