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Re: Outside of the EDT: JOptionPane.showMessageDialog

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In article 
<showMessageDialog-20121227071317@ram.dialup.fu-berlin.de>,
 ram@zedat.fu-berlin.de (Stefan Ram) wrote:

> Knute Johnson <nospam@knutejohnson.com> writes:
> > I looked at the source for JOptionPane and I don't see 
> > anything in there that would lead me to believe that you 
> > could invoke it safely on other than the EDT.
> 
>  Possibly it's the way they are called, in a sequential
>  manner without any callbacks. When the application invokes
>  showMessageDialog, there is no Swing component yet, the
>  application waits synchronously until after the end of
>  execution of showMessageDialog, when again there is no Swing
>  component anymore. So, during the runtime of
>  showMessageDialog, Swing has exclusive control. Maybe this
>  suffices to prevent any problems with multithreading?

I'd say no. If the dialog is not constructed on the EDT, then 
it is constructed on some other thread, e.g. the initial 
thread. At any point, the construction of a component of the 
dialog or the Object(s) referenced in the message parameter may 
result in a Runnable being posted to the EDT, which is started 
with the first invocation of postEvent(). This results in a 
race between the (initial) thread and the EDT. Proving the 
absence of a problem for a particular case would have to rely 
on (undocumented) implementation details.

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

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Re: Outside of the EDT: JOptionPane.showMessageDialog Knute Johnson <nospam@knutejohnson.com> - 2012-12-26 22:03 -0800
  Re: Outside of the EDT: JOptionPane.showMessageDialog "John B. Matthews" <nospam@nospam.invalid> - 2012-12-27 10:23 -0500
    Re: Outside of the EDT: JOptionPane.showMessageDialog Knute Johnson <nospam@knutejohnson.com> - 2012-12-27 09:06 -0800
      Re: Outside of the EDT: JOptionPane.showMessageDialog "John B. Matthews" <nospam@nospam.invalid> - 2012-12-27 16:16 -0500
    Re: Outside of the EDT: JOptionPane.showMessageDialog "John B. Matthews" <nospam@nospam.invalid> - 2012-12-27 16:34 -0500
      Re: Outside of the EDT: JOptionPane.showMessageDialog "John B. Matthews" <nospam@nospam.invalid> - 2012-12-29 10:38 -0500
        Re: Outside of the EDT: JOptionPane.showMessageDialog Lew <lewbloch@gmail.com> - 2012-12-31 12:00 -0800

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