Grabbed from the RoboWiki on Robocode/News:
Hey Fnl, sorry not to have caught this in the beta period, but... I am getting errors with some bots in 1.2.3, such as SilverSurfer and VertiLeach, that look like this:
axeBots.SilverSurfer 2.53.33: Exception: java.util.ConcurrentModificationException
java.util.ConcurrentModificationException
at java.util.AbstractList$Itr.checkForComodification(AbstractList.java:449)
at java.util.AbstractList$Itr.next(AbstractList.java:420)
at robocode.peer.robot.EventManager.processEvents(Unknown Source)
at robocode.peer.RobotPeer.tick(Unknown Source)
at robocode.AdvancedRobot.execute(Unknown Source)
at axeBots.SilverSurfer.run(SilverSurfer.java:268)
at robocode.peer.RobotPeer.run(Unknown Source)
at java.lang.Thread.run(Thread.java:613)
(Actually, an anonymous wiki reader that contacted me on AIM deserves the credit. =)) Double checking in 1.2.2, those bots seem to work fine.
-- Voidious
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Fixed with Robocode 1.2.3A
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