Minecraft didn't responded after i used some end Gateway blocks in my testing world so i can get faster from A to B and back, then i let a firework rocket pass through the gateway and shortly after i let the second one fly through my game didn't respond anymore with this error Message spammed in the log:

[Server thread/FATAL]: Error executing task
java.util.concurrent.ExecutionException: java.lang.NullPointerException
at java.util.concurrent.FutureTask.report(FutureTask.java:122) ~[?:1.8.0_25]
at java.util.concurrent.FutureTask.get(FutureTask.java:192) ~[?:1.8.0_25]
at h.a(SourceFile:47) [h.class:?]
at net.minecraft.server.MinecraftServer.D(SourceFile:604) [MinecraftServer.class:?]
at net.minecraft.server.MinecraftServer.C(SourceFile:560) [MinecraftServer.class:?]
at chd.C(IntegratedServer.java:252) [chd.class:?]
at net.minecraft.server.MinecraftServer.run(SourceFile:464) [MinecraftServer.class:?]
at java.lang.Thread.run(Thread.java:745) [?:1.8.0_25]
Caused by: java.lang.NullPointerException
at ou.c(PlayerChunkMap.java:449) ~[ou.class:?]
at pl.d(SourceFile:342) ~[pl.class:?]
at pa.a(SourceFile:550) ~[pa.class:?]
at lk.a(SourceFile:126) ~[lk.class:?]
at lk$a.a(SourceFile:57) ~[lk$a.class:?]
at hv$1.run(PacketThreadUtil.java:20) ~[hv$1.class:?]
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) ~[?:1.8.0_25]
at java.util.concurrent.FutureTask.run(FutureTask.java:266) ~[?:1.8.0_25]
at h.a(SourceFile:46) ~[h.class:?]
... 5 more

Full log file: latest.log