My minecraft 1.9.4 server keeps crashing:
---- Minecraft Crash Report ----
// Don't be sad, have a hug! <3

Time: 29/05/16 20:10
Description: Watching Server

java.lang.Error
at java.util.concurrent.locks.ReentrantReadWriteLock$NonfairSync.readerShouldBlock(Unknown Source)
at java.util.concurrent.locks.ReentrantReadWriteLock$Sync.tryAcquireShared(Unknown Source)
at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireShared(Unknown Source)
at java.util.concurrent.locks.ReentrantReadWriteLock$ReadLock.lock(Unknown Source)
at ki.c(SourceFile:86)
at ki.a(SourceFile:103)
at yw.db(SourceFile:306)
at yw.bo(SourceFile:353)
at rr.av(SourceFile:1474)
at sa.U(SourceFile:222)
at sb.U(SourceFile:210)
at rr.m(SourceFile:340)
at sa.m(SourceFile:1558)
at sb.m(SourceFile:277)
at yq.m(SourceFile:46)
at aht.a(SourceFile:1517)
at lq.a(SourceFile:717)
at aht.g(SourceFile:1495)
at aht.k(SourceFile:1385)
at lq.k(SourceFile:550)
at net.minecraft.server.MinecraftServer.D(SourceFile:626)
at lb.D(SourceFile:340)
at net.minecraft.server.MinecraftServer.C(SourceFile:554)
at net.minecraft.server.MinecraftServer.run(SourceFile:458)
at java.lang.Thread.run(Unknown Source)

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

– Head –
Thread: Server Watchdog
Stacktrace:
at java.util.concurrent.locks.ReentrantReadWriteLock$NonfairSync.readerShouldBlock(Unknown Source)
at java.util.concurrent.locks.ReentrantReadWriteLock$Sync.tryAcquireShared(Unknown Source)
at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireShared(Unknown Source)
at java.util.concurrent.locks.ReentrantReadWriteLock$ReadLock.lock(Unknown Source)
at ki.c(SourceFile:86)
at ki.a(SourceFile:103)
at yw.db(SourceFile:306)
at yw.bo(SourceFile:353)
at rr.av(SourceFile:1474)
at sa.U(SourceFile:222)
at sb.U(SourceFile:210)
at rr.m(SourceFile:340)
at sa.m(SourceFile:1558)
at sb.m(SourceFile:277)
at yq.m(SourceFile:46)
at aht.a(SourceFile:1517)
at lq.a(SourceFile:717)
at aht.g(SourceFile:1495)
at aht.k(SourceFile:1385)
at lq.k(SourceFile:550)
at net.minecraft.server.MinecraftServer.D(SourceFile:626)
at lb.D(SourceFile:340)
at net.minecraft.server.MinecraftServer.C(SourceFile:554)

– Thread Dump –
Details:
Threads: "Netty Server IO #1" Id=18 RUNNABLE
at sun.nio.ch.WindowsSelectorImpl$SubSelector.poll0(Native Method)
at sun.nio.ch.WindowsSelectorImpl$SubSelector.poll(Unknown Source)
at sun.nio.ch.WindowsSelectorImpl$SubSelector.access$400(Unknown Source)
at sun.nio.ch.WindowsSelectorImpl.doSelect(Unknown Source)
at sun.nio.ch.SelectorImpl.lockAndDoSelect(Unknown Source)

• locked io.netty.channel.nio.SelectedSelectionKeySet@1fb4e4
• locked java.util.Collections$UnmodifiableSet@d85a97
• locked sun.nio.ch.WindowsSelectorImpl@e7df94
  at sun.nio.ch.SelectorImpl.select(Unknown Source)
  at io.netty.channel.nio.NioEventLoop.select(NioEventLoop.java:622)
  at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:310)
  ...

"File IO Thread" Id=32 TIMED_WAITING
at java.lang.Thread.sleep(Native Method)
at bbb.c(SourceFile:44)
at bbb.run(SourceFile:30)
at java.lang.Thread.run(Unknown Source)

"Server Watchdog" Id=26 RUNNABLE
at sun.management.ThreadImpl.dumpThreads0(Native Method)
at sun.management.ThreadImpl.dumpAllThreads(Unknown Source)
at lc.run(SourceFile:43)
at java.lang.Thread.run(Unknown Source)

"Netty Server IO #0" Id=17 RUNNABLE (in native)
at sun.nio.ch.WindowsSelectorImpl$SubSelector.poll0(Native Method)
at sun.nio.ch.WindowsSelectorImpl$SubSelector.poll(Unknown Source)
at sun.nio.ch.WindowsSelectorImpl$SubSelector.access$400(Unknown Source)
at sun.nio.ch.WindowsSelectorImpl.doSelect(Unknown Source)
at sun.nio.ch.SelectorImpl.lockAndDoSelect(Unknown Source)

• locked io.netty.channel.nio.SelectedSelectionKeySet@1e550ac
• locked java.util.Collections$UnmodifiableSet@207520
• locked sun.nio.ch.WindowsSelectorImpl@e09d11
  at sun.nio.ch.SelectorImpl.select(Unknown Source)
  at io.netty.channel.nio.NioEventLoop.select(NioEventLoop.java:622)
  at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:310)
  ...

"Server console handler" Id=15 RUNNABLE (in native)
at java.io.FileInputStream.readBytes(Native Method)
at java.io.FileInputStream.read(Unknown Source)
at java.io.BufferedInputStream.read1(Unknown Source)
at java.io.BufferedInputStream.read(Unknown Source)

• locked java.io.BufferedInputStream@cfe626
  at sun.nio.cs.StreamDecoder.readBytes(Unknown Source)
  at sun.nio.cs.StreamDecoder.implRead(Unknown Source)
  at sun.nio.cs.StreamDecoder.read(Unknown Source)
• locked java.io.InputStreamReader@1caafe3
  at java.io.InputStreamReader.read(Unknown Source)
  ...

"DestroyJavaVM" Id=14 RUNNABLE

"Server thread" Id=12 RUNNABLE
at java.util.concurrent.locks.ReentrantReadWriteLock$NonfairSync.readerShouldBlock(Unknown Source)
at java.util.concurrent.locks.ReentrantReadWriteLock$Sync.tryAcquireShared(Unknown Source)
at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireShared(Unknown Source)
at java.util.concurrent.locks.ReentrantReadWriteLock$ReadLock.lock(Unknown Source)
at ki.c(SourceFile:86)
at ki.a(SourceFile:103)
at yw.db(SourceFile:306)
at yw.bo(SourceFile:353)
...

"Server Infinisleeper" Id=11 TIMED_WAITING
at java.lang.Thread.sleep(Native Method)
at lb$1.run(SourceFile:78)

"Snooper Timer" Id=10 TIMED_WAITING on java.util.TaskQueue@72464f
at java.lang.Object.wait(Native Method)

• waiting on java.util.TaskQueue@72464f
  at java.util.TimerThread.mainLoop(Unknown Source)
  at java.util.TimerThread.run(Unknown Source)

"Attach Listener" Id=5 RUNNABLE

"Signal Dispatcher" Id=4 RUNNABLE

"Finalizer" Id=3 WAITING on java.lang.ref.ReferenceQueue$Lock@804885
at java.lang.Object.wait(Native Method)

• waiting on java.lang.ref.ReferenceQueue$Lock@804885
  at java.lang.ref.ReferenceQueue.remove(Unknown Source)
  at java.lang.ref.ReferenceQueue.remove(Unknown Source)
  at java.lang.ref.Finalizer$FinalizerThread.run(Unknown Source)

"Reference Handler" Id=2 WAITING on java.lang.ref.Reference$Lock@1cb6ce5
at java.lang.Object.wait(Native Method)

• waiting on java.lang.ref.Reference$Lock@1cb6ce5
  at java.lang.Object.wait(Unknown Source)
  at java.lang.ref.Reference.tryHandlePending(Unknown Source)
  at java.lang.ref.Reference$ReferenceHandler.run(Unknown Source)

Stacktrace:
at lc.run(SourceFile:59)
at java.lang.Thread.run(Unknown Source)

– System Details –
Details:
Minecraft Version: 1.9.4
Operating System: Windows 10 (x86) version 10.0
Java Version: 1.8.0_91, Oracle Corporation
Java VM Version: Java HotSpot(TM) Client VM (mixed mode), Oracle Corporation
Memory: 901793480 bytes (860 MB) / 1037959168 bytes (989 MB) up to 1037959168 bytes (989 MB)
JVM Flags: 2 total; -Xmx1024M -Xms1024M
IntCache: cache: 0, tcache: 0, allocated: 12, tallocated: 94
Profiler Position: N/A (disabled)
Player Count: 1 / 6; [ls['Survivalisbest'/110, l='world', x=-74.88, y=109.99, z=62.95]]
Is Modded: Unknown (can't tell)
Type: Dedicated Server (map_server.txt)