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Re: intermittent hang on launch

Rolf Howarth wrote:

At 12:04 -0800 30/1/07, Doug Zwick <email@hidden> wrote: 

Many Java programs use a main routine something like this:

     public static void main (String[] args) {
         SwingUtilities.invokeLater (new Runnable() {
             public void run() {
                 MyMainFrame frame = new MyMainFrame();
                 frame.pack();
                 frame.show();
             }
         });
     }


That shouldn't be necessary. You are explicitly allowed to call Swing
methods from any thread until the component is realized. The problem
is thread safety and calls to paint() from the event loop, but the
component won't be painted until it's shown.

Yes and no. For example, Containers are not synchronized, so adding/ removing Components from multiple threads has concurrency issues with accessing the underlying collection. As for the code fragment I posted, realization occurs during pack(), so pack() and show() must be done on the Swing thread. Constructing the object could be done in- line in main first:

    public static void main (String[] args) {
        final MyMainFrame frame = new MyMainFrame();

        SwingUtilities.invokeLater (new Runnable() {
            public void run() {
                frame.pack();
                frame.show();
            }
        });
    }

I usually find it more convenient to do it all on the Swing thread. More complex situations may require other solutions.
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