org.apache.commons.betwixt.expression
Class ConstantExpression

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

All Implemented Interfaces:

Expression

public class ConstantExpression
extends java.lang.Object
implements Expression

ConstantExpression represents a constant expression.

In other words, evaluate(org.apache.commons.betwixt.expression.Context) returns a value independent of the context.

Version:

$Revision: 438373 $

Author:

James Strachan

Constructor Summary

ConstantExpression()
Base constructor

ConstantExpression(java.lang.Object value)
Convenience constructor sets value property.

Method Summary

java.lang.Object	evaluate(Context context) Evaluate expression against given context.
java.lang.Object	getValue() Gets the constant value of this expression
void	setValue(java.lang.Object value) Sets the constant value of this expression
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

ConstantExpression

public ConstantExpression()

Base constructor

ConstantExpression

public ConstantExpression(java.lang.Object value)

Convenience constructor sets value property.

Parameters:

value - the Object which is the constant value for this expression

Method Detail

evaluate

public java.lang.Object evaluate(Context context)

Evaluate expression against given context.

Specified by:

evaluate in interface Expression

Parameters:

context - evaluate expression against this context

Returns:

current value of value property

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

getValue

public java.lang.Object getValue()

Gets the constant value of this expression

Returns:

this expression's constant value

setValue

public void setValue(java.lang.Object value)

Sets the constant value of this expression

Parameters:

value - the constant value for this expression

toString

public java.lang.String toString()

Returns something useful for logging

Overrides:

toString in class java.lang.Object

Returns:

something useful for logging