[UIMA-1986] Fix Synchronization on Long could deadlock Reported by Findbugs

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.3.1AS
• Fix Version/s: 2.3.1AS
• Component/s: Async Scaleout
• Assignee: Jaroslaw Cwiklik
• Reporter: Jaroslaw Cwiklik
• Created: 04/Jan/11 18:51
• Updated: 04/Jan/11 18:54
• Resolved: 04/Jan/11 18:54

Description

Local class StackDumpTimer in PrimitiveAnalysisEngineController_impl is synchronizing a block of code using a primitive (Long) which is not a good idea.
Finbugs documentation on this bug says:

"DL: Synchronization on boxed primitive could lead to deadlock (DL_SYNCHRONIZATION_ON_BOXED_PRIMITIVE)

The code synchronizes on a boxed primitive constant, such as an Integer.

private static Integer count = 0;
...
synchronized(count)

{ count++; }

...
Since Integer objects can be cached and shared, this code could be synchronizing on the same object as other, unrelated code, leading to unresponsiveness and possible deadlock"