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Re: Best strategy to follow a state transition?

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In article <505c4afc$0$6941$e4fe514c@news2.news.xs4all.nl>,
 Ben Engbers <Ben.dot.Engbers@Be-Logical.dot.nl> wrote:

> In my program, I know that at some moment the value of a variable X 
> will change from value 1 to value 2. I am not interested in the value 
> of X itself but the transition should trigger an event. Example, if 
> the value of a stock will reach a certain value, I want to sell but 
> after that I'm not interested in the value anymore (until it might 
> reach another break-value).
> 
> Of course I could program this as:
> if oldvalue <= testvalue and newvalue > testvalue then
>   do something;
>   oldvalue = newvalue;
> end
> But suppose that there are a lot of variables that I need to watch 
> and I don't want to write a test for every one.
> 
> Wat is the best strategy to watch the transition?

It sounds like you want a bound property:

<http://docs.oracle.com/javase/tutorial/javabeans/writing/properties.html>

-- 
John B. Matthews
trashgod at gmail dot com
<http://sites.google.com/site/drjohnbmatthews>

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Best strategy to follow a state transition? Ben Engbers <Ben.dot.Engbers@Be-Logical.dot.nl> - 2012-09-21 13:09 +0200
  Re: Best strategy to follow a state transition? "John B. Matthews" <nospam@nospam.invalid> - 2012-09-21 07:36 -0400
  Re: Best strategy to follow a state transition? Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-09-21 09:51 -0400
    Re: Best strategy to follow a state transition? Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2012-09-21 10:26 -0700
  Re: Best strategy to follow a state transition? Daniele Futtorovic <da.futt.news@laposte-dot-net.invalid> - 2012-09-22 00:08 +0200

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