Package org.apache.commons.jxpath.ri.compiler

Class ExtensionFunction

java.lang.Object

org.apache.commons.jxpath.ri.compiler.Expression

org.apache.commons.jxpath.ri.compiler.Operation

org.apache.commons.jxpath.ri.compiler.ExtensionFunction

public class ExtensionFunction
extends Operation

Represents an element of the parse tree representing an extension function call.

Version:

$Revision: 652845 $ $Date: 2008-05-02 12:46:46 -0500 (Fri, 02 May 2008) $

Author:

Dmitri Plotnikov

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.commons.jxpath.ri.compiler.Expression

Expression.PointerIterator, Expression.ValueIterator

Field Summary

Fields

Modifier and Type	Field	Description
private QName	functionName

Fields inherited from class org.apache.commons.jxpath.ri.compiler.Expression

NOT_A_NUMBER, ONE, ZERO

Fields inherited from class org.apache.commons.jxpath.ri.compiler.Operation

args

Constructor Summary

Constructors

Constructor	Description
ExtensionFunction(QName functionName, Expression[] args)	Create a new ExtensionFunction.

Method Summary

Modifier and Type	Method	Description
java.lang.Object	compute(EvalContext context)	Evaluates the expression.
boolean	computeContextDependent()	An extension function gets the current context, therefore it MAY be context dependent.
java.lang.Object	computeValue(EvalContext context)	Evaluates the expression.
private java.lang.Object	convert(java.lang.Object object)	Convert any incoming context to a value.
QName	getFunctionName()	Get the function name
java.lang.String	toString()

Methods inherited from class org.apache.commons.jxpath.ri.compiler.Expression

isContextDependent, iterate, iteratePointers

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from class org.apache.commons.jxpath.ri.compiler.Operation

getArguments

Field Detail

functionName

private QName functionName

Constructor Detail

ExtensionFunction

public ExtensionFunction(QName functionName,
                         Expression[] args)

Create a new ExtensionFunction.

Parameters:

functionName - name of the function

args - Expression[] of function args

Method Detail

getFunctionName

public QName getFunctionName()

Get the function name

Returns:

QName

computeContextDependent

public boolean computeContextDependent()

An extension function gets the current context, therefore it MAY be context dependent.

Overrides:

computeContextDependent in class Operation

Returns:

true

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

compute

public java.lang.Object compute(EvalContext context)

Description copied from class: Expression

Evaluates the expression. If the result is a node set, returns the first element of the node set.

Specified by:

compute in class Expression

Parameters:

context - evaluation context

Returns:

Object

computeValue

public java.lang.Object computeValue(EvalContext context)

Description copied from class: Expression

Evaluates the expression. If the result is a node set, returns the first element of the node set.

Specified by:

computeValue in class Expression

Parameters:

context - evaluation context

Returns:

Object

convert

private java.lang.Object convert(java.lang.Object object)

Convert any incoming context to a value.

Parameters:

object - Object to convert

Returns:

context value or object unscathed.