org.apache.commons.betwixt.expression
Class VariableExpression

java.lang.Object
  org.apache.commons.betwixt.expression.VariableExpression

All Implemented Interfaces:

Expression

public class VariableExpression
extends java.lang.Object
implements Expression

VariableExpression represents a variable expression such as $foo which returns the value of the given variable.

Version:

$Revision: 438373 $

Author:

James Strachan

Constructor Summary

VariableExpression()
Base constructor

VariableExpression(java.lang.String variableName)
Convenience constructor sets VariableName property

Method Summary

java.lang.Object	evaluate(Context context) Return the value of a context variable.
java.lang.String	getVariableName() Gets the variable name
void	setVariableName(java.lang.String variableName) Sets the variable name
java.lang.String	toString() Returns something useful for logging
void	update(Context context, java.lang.String newValue) Do nothing

Methods inherited from class java.lang.Object

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

Constructor Detail

VariableExpression

public VariableExpression()

Base constructor

VariableExpression

public VariableExpression(java.lang.String variableName)

Convenience constructor sets VariableName property

Parameters:

variableName - the name of the context variable whose value will be returned by an evaluation

Method Detail

evaluate

public java.lang.Object evaluate(Context context)

Return the value of a context variable.

Specified by:

evaluate in interface Expression

Parameters:

context - evaluate against this context

Returns:

the value of the context variable named by the VariableName property

getVariableName

public java.lang.String getVariableName()

Gets the variable name

Returns:

the name of the context variable whose value will be returned by an evaluation

setVariableName

public void setVariableName(java.lang.String variableName)

Sets the variable name

Parameters:

variableName - the name of the context variable whose value will be returned by an evaluation

update

public void update(Context context,
                   java.lang.String newValue)

Do nothing

Specified by:

update in interface Expression

Parameters:

context - update this Context

newValue - the new value for this expression

See Also:

Expression

toString

public java.lang.String toString()

Returns something useful for logging

Overrides:

toString in class java.lang.Object

Returns:

something useful for logging