net.sf.saxon.query
Class XQueryFunction

java.lang.Object
  extended by net.sf.saxon.query.XQueryFunction
All Implemented Interfaces:
Serializable, SourceLocator, LocationProvider, SaxonLocator, Container, Declaration, InstructionInfo, Locator

public class XQueryFunction
extends Object
implements InstructionInfo, Container, Declaration

See Also:
Serialized Form

Constructor Summary
XQueryFunction()
          Create an XQuery function
 
Method Summary
 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)
          Get the line number within the document or module containing a particular location
 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)
          Get the URI of the document or module containing a particular location
 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
 void setExecutable(Executable exec)
          Set the executable in which this function is contained
 void setMemoFunction(boolean isMemoFunction)
          Set that this is, or is not, a memo function.
 void setStaticContext(StaticContext env)
          Set the static context for this function
 
Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

XQueryFunction

public XQueryFunction()
Create an XQuery function

Method Detail

getBody

public Expression getBody()
Get the body of the function

Returns:
the expression making up the body of the function

getFunctionName

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

Returns:
the name of the function as a structured QName

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

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

getResultType

public SequenceType getResultType()
Get the result type of the function

Returns:
the declared result type

setExecutable

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

Parameters:
exec - the executable

getExecutable

public Executable getExecutable()
Get the executable in which this function is contained

Specified by:
getExecutable in interface Container
Returns:
the executable

getLocationProvider

public LocationProvider getLocationProvider()
Get the LocationProvider allowing location identifiers to be resolved.

Specified by:
getLocationProvider in interface Container
Returns:
the location provider

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

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

getNumberOfArguments

public int getNumberOfArguments()
Get the arity of the function

Returns:
the arity (the number of arguments)

registerReference

public void registerReference(UserFunctionCall 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

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

optimize

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

Throws:
XPathException

fixupReferences

public void fixupReferences(StaticContext env)
                     throws XPathException
Fix up references to this function

Parameters:
env - the static context
Throws:
XPathException

checkReferences

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

Parameters:
visitor - the expression visitor
Throws:
XPathException

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

getUserFunction

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

Returns:
the compiled function object

getConstructType

public int getConstructType()
Get the type of construct. This will be a constant in class Location.

Specified by:
getConstructType in interface InstructionInfo

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)

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 SourceLocator
Specified by:
getSystemId in interface InstructionInfo
Specified by:
getSystemId in interface Locator

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 SourceLocator
Specified by:
getLineNumber in interface InstructionInfo
Specified by:
getLineNumber in interface Locator

getPublicId

public String getPublicId()
Return the public identifier for the current document event.

Specified by:
getPublicId in interface SourceLocator
Specified by:
getPublicId in interface Locator
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 SourceLocator
Specified by:
getColumnNumber in interface Locator
Returns:
The column number, or -1 if none is available.
See Also:
getLineNumber()

getSystemId

public String getSystemId(long locationId)
Description copied from interface: LocationProvider
Get the URI of the document or module containing a particular location

Specified by:
getSystemId in interface LocationProvider
Parameters:
locationId - identifier of the location in question (as passed down the Receiver pipeline)
Returns:
the URI of the document or module.

getLineNumber

public int getLineNumber(long locationId)
Description copied from interface: LocationProvider
Get the line number within the document or module containing a particular location

Specified by:
getLineNumber in interface LocationProvider
Parameters:
locationId - identifier of the location in question (as passed down the Receiver pipeline)
Returns:
the line number within the document or module.

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

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

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

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
Returns:
typically Configuration.XSLT or Configuration.XQUERY

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


Copyright (C) Michael H. Kay. All rights reserved.