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

Class VariableReference

java.lang.Object

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

org.apache.commons.jxpath.ri.compiler.VariableReference

public class VariableReference
extends Expression

An element of the compile tree holding a variable reference.

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	varName

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

NOT_A_NUMBER, ONE, ZERO

Constructor Summary

Constructors

Constructor	Description
VariableReference(QName varName)	Create a new VariableReference.

Method Summary

Modifier and Type	Method	Description
java.lang.Object	compute(EvalContext context)	Evaluates the expression.
boolean	computeContextDependent()	Implemented by subclasses and result is cached by isContextDependent()
java.lang.Object	computeValue(EvalContext context)	Returns the value of the variable.
QName	getVariableName()	Get the variable name.
boolean	isContextDependent()	Returns true if this expression should be re-evaluated each time the current position in the context changes.
java.lang.String	toString()

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

iterate, iteratePointers

Methods inherited from class java.lang.Object

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

Field Detail

varName

private QName varName

Constructor Detail

VariableReference

public VariableReference(QName varName)

Create a new VariableReference.

Parameters:

varName - variable name

Method Detail

getVariableName

public QName getVariableName()

Get the variable name.

Returns:

QName

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

isContextDependent

public boolean isContextDependent()

Description copied from class: Expression

Returns true if this expression should be re-evaluated each time the current position in the context changes.

Overrides:

isContextDependent in class Expression

Returns:

boolean

computeContextDependent

public boolean computeContextDependent()

Description copied from class: Expression

Implemented by subclasses and result is cached by isContextDependent()

Specified by:

computeContextDependent in class Expression

Returns:

calculated context-dependentness as boolean

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)

Returns the value of the variable.

Specified by:

computeValue in class Expression

Parameters:

context - EvalContext against which to compute the variable's value.

Returns:

Object