[MC-59115] Constant Server Crash

ive reset our map a couple times now, but it always starts eventually getting to the point it eventually crashes completely an wont stay up an always with the same error displayed on console

[23:16:36] [Server thread/ERROR]: Encountered an unexpected exception
java.lang.NoClassDefFoundError: Could not initialize class b
at ud.f(SourceFile:1156) ~inecraft_server.jar:?]
at uj.a(SourceFile:157) ~inecraft_server.jar:?]
at azn.a(SourceFile:329) ~inecraft_server.jar:?]
at azn.a(SourceFile:94) ~inecraft_server.jar:?]
at azn.a(SourceFile:82) ~inecraft_server.jar:?]
at ou.e(SourceFile:130) ~inecraft_server.jar:?]
at ou.c(SourceFile:81) ~inecraft_server.jar:?]
at ot.<init>(SourceFile:36) ~inecraft_server.jar:?]
at os.a(SourceFile:228) ~inecraft_server.jar:?]
at os.a(SourceFile:265) ~inecraft_server.jar:?]
at qi.a(SourceFile:226) ~inecraft_server.jar:?]
at qi.c(SourceFile:278) ~inecraft_server.jar:?]
at qi.a(SourceFile:133) ~inecraft_server.jar:?]
at po.b(SourceFile:86) ~inecraft_server.jar:?]
at po.c(SourceFile:52) ~inecraft_server.jar:?]
at ft.a(SourceFile:167) ~inecraft_server.jar:?]
at pd.c(SourceFile:135) ~inecraft_server.jar:?]
at net.minecraft.server.MinecraftServer.x(SourceFile:600) ~inecraft_server.jar:?]
at nu.x(SourceFile:284) ~inecraft_server.jar:?]
at net.minecraft.server.MinecraftServer.w(SourceFile:510) ~inecraft_server.jar:?]
at net.minecraft.server.MinecraftServer.run(SourceFile:426) inecraft_server.jar:?]
at java.lang.Thread.run(Unknown Source) [?:1.7.0_01]

Unf it dosent produce a Crash report so the above is all i have to go on.