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Ticket #1471 (closed defect: wontfix)

Opened 2012-09-11T15:59:05-05:00

Last modified 2014-08-20T11:59:25-05:00

Concurrent legacy plugin execution can cause problems

Reported by:	curtis	Owned by:	bdezonia
Priority:	critical	Milestone:	imagej-2.0.0
Component:	Legacy Compatibility	Version:	2.0.0-beta4
Severity:	critical	Keywords:
Cc:		Blocked By:
Blocking:	#1011

Description

If you execute many legacy plugins very quickly, there may be bugs relating to timing issues. For example, if you run Blobs three times in quick succession (Shift+BBB) on some systems, the legacy layer can get out of sync, resulting in exceptions.

Change History

comment:1 Changed 2012-09-11T16:03:08-05:00 by curtis

Summary changed from Concurrent legacy plugin execution can fail to Concurrent legacy plugin execution can cause problems

I ran Blobs several times, until a duplicate Blobs window appeared (i.e., there were more Blobs windows than number of times I pressed Shift+B; presumably at least two of the display viewers actually correspond to the same copy of the Blobs dataset). I then pressed W to close a Blobs window, which was successful. But pressing W repeatedly to close out all the windows eventually results in the following exception:

Uncaught exception in thread Thread[plugin thread,6,plugin thread group]
java.lang.NullPointerException
	at imagej.legacy.translate.LegacyUtils.isBinary(LegacyUtils.java:412)
	at imagej.legacy.translate.Harmonizer.updateLegacyImage(Harmonizer.java:117)
	at imagej.legacy.plugin.LegacyCommand$LegacyCommandThread.updateImagePlusesFromDisplays(LegacyCommand.java:343)
	at imagej.legacy.plugin.LegacyCommand$LegacyCommandThread.run(LegacyCommand.java:177)

Maybe because one copy of that particular Blobs ImagePlus was already closed out, so attempting to close it again causes problems?

A related issue is that if you press Shift+BBB fast enough, when the multiple Blobs windows appear, they are all titled "blobs.gif" rather than blobs.gif, blobs-1.gif and blobs-2.gif. Looks like a race condition in the display event hierarchy somewhere. (We can file a separate ticket for it later if addressing the rest of this ticket doesn't fix it.)

comment:2 Changed 2014-08-20T11:59:25-05:00 by curtis

Status changed from new to closed
Resolution set to wontfix

We are no longer supporting use of ImageJ 1.x commands from modern ImageJ2 UIs, so this issue is now moot.