de.tsl2.nano.historize

Class Volatile<T>

java.lang.Object

de.tsl2.nano.historize.Volatile<T>

Direct Known Subclasses:

VolatileResult

public class Volatile<T>
extends Object

Same as an Expiring Reference. solution for getter methods doing a long time calculation to evaluate their value - but called more than once in a short time. mostly, the value wont change between two user actions, so this class provides a mechanism to hold the evaluated value for a very short time.

use:

 if (myVolatileValue.expired()) {
  ...evaluate the value...
  myVolatileValue.set(myNewValue);
 }
 return myVolatileValue.get();
 

Version:

$Revision$

Author:

Tom

Constructor Summary

Constructors

Constructor and Description
Volatile(long period)
Volatile(long period, T value) constructor

Method Summary

Modifier and Type	Method and Description
protected void	activate() activate
boolean	expired() expired
T	get()
T	invalidate()
T	set(T value)
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

Volatile

public Volatile(long period)

Volatile

public Volatile(long period,
                T value)

constructor

Parameters:

period - of milliseconds to hold the value. this should be a value smaller than 1sec (< 1000)

value - (optional) initial value.

Method Detail

expired

public boolean expired()

expired

Returns:

true, if value is to old.

get

public T get()

invalidate

public T invalidate()

set

public T set(T value)

activate

protected void activate()

activate

toString

public String toString()

Overrides:

toString in class Object