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dbal presents ...



This simple scenario frequently throws the following exception and hangs
up the IDE when either the Pause button or the Reset button is clicked
while the scenario is running.

Once the exception is thrown, it is necessary to shut down and restart the
Greenfoot IDE to run the scenario again.

The scenario is being posted solely so that I can solicit information on the
forum as to whether or not this is normal, and if so, why?

Exception in thread "SimulationThread" java.lang.IllegalMonitorStateException
at java.util.concurrent.locks.ReentrantReadWriteLock$Sync.tryRelease(
at java.util.concurrent.locks.AbstractQueuedSynchronizer.release(
at java.util.concurrent.locks.ReentrantReadWriteLock$WriteLock.unlock(
at greenfoot.core.Simulation.runOneLoop(

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Tags: demo test

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It's not normal and sounds like a bug in Greenfoot, possibly to do with the delay method - I've explained more in the forum.

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