Crashed from "Watching Server" No idea what this is or why it happened. No one was online to cause a crash.

crash-2015-11-13_05.17.39-server.txt:

---- Minecraft Crash Report ----
// Everything's going to plan. No, really, that was supposed to happen.

Time: 11/13/15 5:17 AM
Description: Watching Server

java.lang.Error
at adk.b(SourceFile:156)
at zm.a(SourceFile:431)
at zn.b(SourceFile:774)
at lr.b(SourceFile:177)
at rn.e(SourceFile:1284)
at ayy.a(SourceFile:150)
at mm.b(SourceFile:298)
at mm.e(SourceFile:340)
at mb.a(SourceFile:725)
at ek.l(SourceFile:382)
at ma.c(SourceFile:204)
at net.minecraft.server.MinecraftServer.D(SourceFile:642)
at la.D(SourceFile:314)
at net.minecraft.server.MinecraftServer.C(SourceFile:552)
at net.minecraft.server.MinecraftServer.run(SourceFile:456)
at java.lang.Thread.run(Thread.java:745)

A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

– Head –
Stacktrace:
at adk.b(SourceFile:156)
at zm.a(SourceFile:431)
at zn.b(SourceFile:774)
at lr.b(SourceFile:177)
at rn.e(SourceFile:1284)
at ayy.a(SourceFile:150)
at mm.b(SourceFile:298)
at mm.e(SourceFile:340)
at mb.a(SourceFile:725)
at ek.l(SourceFile:382)
at ma.c(SourceFile:204)
at net.minecraft.server.MinecraftServer.D(SourceFile:642)
at la.D(SourceFile:314)
at net.minecraft.server.MinecraftServer.C(SourceFile:552)

– Thread Dump –
Details:
Threads: "SIGHUP handler" Id=104 RUNNABLE

"File IO Thread" Id=29 TIMED_WAITING
at java.lang.Thread.sleep(Native Method)
at baw.c(SourceFile:51)
at baw.run(SourceFile:30)
at java.lang.Thread.run(Thread.java:745)

"Server Watchdog" Id=25 RUNNABLE
at sun.management.ThreadImpl.dumpThreads0(Native Method)
at sun.management.ThreadImpl.dumpAllThreads(ThreadImpl.java:446)
at lb.run(SourceFile:43)
at java.lang.Thread.run(Thread.java:745)

"RCON Listener #1" Id=24 RUNNABLE (in native)
at java.net.PlainSocketImpl.socketAccept(Native Method)
at java.net.AbstractPlainSocketImpl.accept(AbstractPlainSocketImpl.java:409)
at java.net.ServerSocket.implAccept(ServerSocket.java:545)
at java.net.ServerSocket.accept(ServerSocket.java:513)
at nd.run(SourceFile:69)
at java.lang.Thread.run(Thread.java:745)

"Netty Epoll Server IO #1" Id=19 RUNNABLE (in native)
at io.netty.channel.epoll.Native.epollWait(Native Method)
at io.netty.channel.epoll.EpollEventLoop.epollWait(EpollEventLoop.java:194)
at io.netty.channel.epoll.EpollEventLoop.run(EpollEventLoop.java:219)
at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:116)
at java.lang.Thread.run(Thread.java:745)

"Netty Epoll Server IO #0" Id=18 RUNNABLE (in native)
at io.netty.channel.epoll.Native.epollWait(Native Method)
at io.netty.channel.epoll.EpollEventLoop.epollWait(EpollEventLoop.java:194)
at io.netty.channel.epoll.EpollEventLoop.run(EpollEventLoop.java:219)
at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:116)
at java.lang.Thread.run(Thread.java:745)

"DestroyJavaVM" Id=14 RUNNABLE

"Server thread" Id=12 RUNNABLE
at adk.b(SourceFile:156)
at zm.a(SourceFile:431)
at zn.b(SourceFile:774)
at lr.b(SourceFile:177)
at rn.e(SourceFile:1284)
at ayy.a(SourceFile:150)
at mm.b(SourceFile:298)
at mm.e(SourceFile:340)
...

"Server Infinisleeper" Id=11 TIMED_WAITING
at java.lang.Thread.sleep(Native Method)
at la$1.run(SourceFile:77)

"Snooper Timer" Id=10 TIMED_WAITING on java.util.TaskQueue@44792b54
at java.lang.Object.wait(Native Method)

• waiting on java.util.TaskQueue@44792b54
  at java.util.TimerThread.mainLoop(Timer.java:552)
  at java.util.TimerThread.run(Timer.java:505)

"Signal Dispatcher" Id=4 RUNNABLE

"Finalizer" Id=3 WAITING on java.lang.ref.ReferenceQueue$Lock@4046b703
at java.lang.Object.wait(Native Method)

• waiting on java.lang.ref.ReferenceQueue$Lock@4046b703
  at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:143)
  at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:164)
  at java.lang.ref.Finalizer$FinalizerThread.run(Finalizer.java:209)

"Reference Handler" Id=2 WAITING on java.lang.ref.Reference$Lock@544216f
at java.lang.Object.wait(Native Method)

• waiting on java.lang.ref.Reference$Lock@544216f
  at java.lang.Object.wait(Object.java:502)
  at java.lang.ref.Reference$ReferenceHandler.run(Reference.java:157)

Stacktrace:
at lb.run(SourceFile:59)
at java.lang.Thread.run(Thread.java:745)

– System Details –
Details:
Minecraft Version: 15w46a
Operating System: Linux (amd64) version 4.1.10-17.31.amzn1.x86_64
Java Version: 1.8.0_65, Oracle Corporation
Java VM Version: OpenJDK 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 212975760 bytes (203 MB) / 445149184 bytes (424 MB) up to 508887040 bytes (485 MB)
JVM Flags: 0 total;
IntCache: cache: 0, tcache: 0, allocated: 12, tallocated: 94
Profiler Position: N/A (disabled)
Player Count: 0 / 25; []
Is Modded: Unknown (can't tell)
Type: Dedicated Server (map_server.txt)