Re: paint program using canvas

From:

Joshua Cranmer <Pidgeot18@verizon.invalid>

Newsgroups:

comp.lang.java.programmer

Date:

Sun, 16 Aug 2009 18:16:22 -0400

Message-ID:

<h6a0fo$4s2$1@news-int2.gatech.edu>

Lew wrote:

I'm not saying you're wrong. I'm just curious how AWT is immune to a
phenomenon that seems to grip every other GUI invented, for Java or
otherwise.

Judging from a brief glance at some of the AWT code, the AWT does a lot
more synchronization (java.awt.List has 33 instances of synchronized,
whereas javax.swing.JList has 0 [1]). At the very least, it can be used
in a multithreaded manner--simple operations would not need to be
proxied to work correctly.

Or perhaps a more correct answer is that Sun more or less abandoned the
AWT and have not bothered to recommend that people keep to the EDT.

And why do Sun engineers say that AWT cannot keep the multithreaded
promise?

Well, multithreaded programming is insanely hard. I have to imagine that
they judged that ensuring correct functionality without the negative
side-effects of multithreading was too difficult compared to using an
event queue model.

[1] But both use Vector, which is of course a synchronized collection.
--
Beware of bugs in the above code; I have only proved it correct, not
tried it. -- Donald E. Knuth