---- Minecraft Crash Report ----
// You're mean.

Time: 8/4/14 11:16 AM
Description: Exception in server tick loop

java.util.ConcurrentModificationException
	at java.util.HashMap$HashIterator.nextNode(HashMap.java:1429)
	at java.util.HashMap$KeyIterator.next(HashMap.java:1453)
	at qi.a(SourceFile:163)
	at net.minecraft.server.MinecraftServer.y(SourceFile:614)
	at net.minecraft.server.MinecraftServer.x(SourceFile:530)
	at cxc.x(SourceFile:155)
	at net.minecraft.server.MinecraftServer.run(SourceFile:446)
	at java.lang.Thread.run(Thread.java:745)


A detailed walkthrough of the error, its code path and all known details is as follows:
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-- System Details --
Details:
	Minecraft Version: 14w31a
	Operating System: Mac OS X (x86_64) version 10.9.3
	Java Version: 1.8.0_05, Oracle Corporation
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
	Memory: 3576863936 bytes (3411 MB) / 4168613888 bytes (3975 MB) up to 4168613888 bytes (3975 MB)
	JVM Flags: 2 total; -Xmx4096M -Xms4096M
	IntCache: cache: 0, tcache: 60, allocated: 12, tallocated: 94
	Profiler Position: N/A (disabled)
	Player Count: 1 / 8; [qr['AppTux'/47, l='1.7-1.8 Survival', x=-211.56, y=76.85, z=-519.32]]
	Type: Integrated Server (map_client.txt)
	Is Modded: Probably not. Jar signature remains and both client + server brands are untouched.