[rfc][icedtea-web][policyeditor] Invoking runnables on EDT

[Jiri Vanek]

On 06/24/2014 09:08 PM, Andrew Azores wrote:
> Hi,
>
> PolicyEditor has a few odd cases with window resizing and with "changes made" being marked as true when the editor is opened without any arguments. Both of these cases arise because although the EDT is the current thread when these actions are taken, they are (for safety, in case they are invoked by a non-EDT thread) wrapped in a SwingUtilities.invokeLater call. In the case of "changes made", this leads to addNewCodebase("") (adding the default all-applets codebase) marking "changes made" as true when the PolicyEditor is instantiated, even though the constructor has setChangesMade(false) immediately after the addNewCodebase call. This happens because the addNewCodebase() call updates the UI and so its main
> functionality is within an invokeLater - including the setChangesMade(true) call. Although a simple fix would be to pull the setChangesMade out of the invokeLater block, this would mean that the editor could potentially report changes made before the UI updates, which I'd like to avoid. Another solution would be to also wrap the setChangesMade(false) in the constructor in yet another invokeLater, but this is messy, and as this doesn't touch any UI elements it's also unnecessary. And another solution, which this patch implements, is to use a helper method, here called invokeRunnableOrEnqueueLater, which replaces SwingUtilities.invokeLater in the PolicyEditor. If the current thread is already the EDT then it
> calls Runnable#run() directly on its sole parameter. If the current thread is not the EDT then the runnable argument is passed along to SwingUtilities.invokeLater to be enqueued and processed as usual.
>
> A similar technique was used for updateCheckboxes/updateCheckboxesInvokeAndWait/updateCheckboxesImpl, although in that case it was SwingUtilities.invokeAndWait rather than invokeLater. These have been slightly refactored to go along with the new method.
>
> Thanks,
>

This looks ok to me.


J.