org.apache.commons.betwixt.expression
Class EmptyExpression

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

All Implemented Interfaces:

Expression

public class EmptyExpression
extends java.lang.Object
implements Expression

EmptyExpression returns the same value as is passed in.

See evaluate(org.apache.commons.betwixt.expression.Context).

Version:

$Revision: 438373 $

Author:

James Strachan

Constructor Summary

EmptyExpression()
Should this be private?

Method Summary

java.lang.Object	evaluate(Context context) Return the bean we're evaluating.
static EmptyExpression	getInstance() Gets the singleton instance.
java.lang.String	toString() Return 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

EmptyExpression

public EmptyExpression()

Should this be private?

Method Detail

getInstance

public static EmptyExpression getInstance()

Gets the singleton instance.

Returns:

the EmptyExpression singleton.

evaluate

public java.lang.Object evaluate(Context context)

Return the bean we're evaluating.

Specified by:

evaluate in interface Expression

Parameters:

context - evaluate against this Context

Returns:

the value of the expression

See Also:

Expression

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()

Return something useful for logging.

Overrides:

toString in class java.lang.Object

Returns:

short name for this class