Db4o WeakReference Collector…help?

Let me know if you have any input?

<—pasted to db4o user forums–>

Hi guys

I’ve been using db4o in my application for about a year now, and recently added new functionality. I say that to refer to this most weird “unexpected error” I ran into:

 Java Threads: ( => current thread )
  0x02c28c00 JavaThread “db4o WeakReference collector” daemon [_thread_blocked, id=68724, stack(0x036e0000,0x03730000)]
  0x02b51c00 JavaThread “db4o WeakReference collector” daemon [_thread_blocked, id=68112, stack(0x03690000,0x036e0000)]
  0x02c60400 JavaThread “DefaultQuartzScheduler_QuartzSchedulerThread” [_thread_blocked, id=68872, stack(0x031c0000,0x03210000)]
  0x02c51800 JavaThread “DefaultQuartzScheduler_Worker-10” [_thread_blocked, id=68624, stack(0x03170000,0x031c0000)]
  0x02c4dc00 JavaThread “DefaultQuartzScheduler_Worker-9” [_thread_blocked, id=68140, stack(0x03120000,0x03170000)]
  0x02c4d800 JavaThread “DefaultQuartzScheduler_Worker-8” [_thread_blocked, id=66352, stack(0x030d0000,0x03120000)]
  0x02c44800 JavaThread “DefaultQuartzScheduler_Worker-7” [_thread_blocked, id=64736, stack(0x03080000,0x030d0000)]
  0x02c44000 JavaThread “DefaultQuartzScheduler_Worker-6” [_thread_blocked, id=58820, stack(0x03030000,0x03080000)]
  0x02c4b800 JavaThread “DefaultQuartzScheduler_Worker-5” [_thread_blocked, id=69516, stack(0x02fe0000,0x03030000)]
  0x02c4b400 JavaThread “DefaultQuartzScheduler_Worker-4” [_thread_blocked, id=66304, stack(0x02f90000,0x02fe0000)]
  0x02c3a000 JavaThread “DefaultQuartzScheduler_Worker-3” [_thread_blocked, id=68752, stack(0x02f40000,0x02f90000)]
  0x02c96800 JavaThread “DefaultQuartzScheduler_Worker-2” [_thread_in_vm, id=61796, stack(0x02e40000,0x02e90000)]
  0x02bf6800 JavaThread “DefaultQuartzScheduler_Worker-1” [_thread_blocked, id=66348, stack(0x02da0000,0x02df0000)]
  0x02bc7800 JavaThread “WrapperSimpleAppMain” [_thread_blocked, id=64364, stack(0x02e90000,0x02ee0000)]
  0x00296c00 JavaThread “DestroyJavaVM” [_thread_blocked, id=67408, stack(0x00640000,0x00690000)]
  0x02859c00 JavaThread “Wrapper-Connection” daemon [_thread_in_native, id=67684, stack(0x02df0000,0x02e40000)]
  0x028b9000 JavaThread “Wrapper-Control-Event-Monitor” daemon [_thread_blocked, id=68824, stack(0x02d50000,0x02da0000)]
  0x027f1800 JavaThread “Low Memory Detector” daemon [_thread_blocked, id=61536, stack(0x02aa0000,0x02af0000)]
  0x027eb400 JavaThread “CompilerThread0” daemon [_thread_blocked, id=69340, stack(0x02a50000,0x02aa0000)]
  0x027e9c00 JavaThread “Attach Listener” daemon [_thread_blocked, id=68924, stack(0x02a00000,0x02a50000)]
  0x027e8800 JavaThread “Signal Dispatcher” daemon [_thread_blocked, id=67632, stack(0x029b0000,0x02a00000)]
  0x027e3800 JavaThread “Finalizer” daemon [_thread_blocked, id=66412, stack(0x02960000,0x029b0000)]
  0x027df000 JavaThread “Reference Handler” daemon [_thread_blocked, id=65108, stack(0x02910000,0x02960000)]

I’ve tried googling and searching the forums but there doesn’t seem to be similar problems.I came across COR-1450 and COR-1504 both dealing with WeakReferences but not the same error. Based upon my understanding of Weak References, my assumption that this problem is in the implementation of db4o using a WeakHashMap? Or could this possibly have resulted from my own stupidity in code?

I’m currently downloading the most recent version of db4o to test.

Any help or guidance would be appreciated!

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