Server log (it say "please report this to spigotmc"):

[08:54:04] [Spigot Watchdog Thread/ERROR]: The server has stopped responding!
[08:54:04] [Spigot Watchdog Thread/ERROR]: Please report this to http://www.spigotmc.org/
[08:54:04] [Spigot Watchdog Thread/ERROR]: Be sure to include ALL relevant console errors and Minecraft crash reports
[08:54:04] [Spigot Watchdog Thread/ERROR]: Spigot version: git-Spigot-f928e7a-994b2aa (MC: 1.8.7)
[08:54:04] [Spigot Watchdog Thread/ERROR]: ------------------------------
[08:54:04] [Spigot Watchdog Thread/ERROR]: Server thread dump (Look for plugins here before reporting to Spigot!):
[08:54:04] [Spigot Watchdog Thread/ERROR]: ------------------------------
[08:54:04] [Spigot Watchdog Thread/ERROR]: Current Thread: Server thread
[08:54:04] [Spigot Watchdog Thread/ERROR]: PID: 28 | Suspended: false | Native: true | State: RUNNABLE
[08:54:04] [Spigot Watchdog Thread/ERROR]: Stack:
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.io.FileOutputStream.close0(Native Method)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.io.FileOutputStream.access$000(FileOutputStream.java:53)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.io.FileOutputStream$1.close(FileOutputStream.java:356)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.io.FileDescriptor.closeAll(FileDescriptor.java:212)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.io.FileOutputStream.close(FileOutputStream.java:354)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.zip.DeflaterOutputStream.close(DeflaterOutputStream.java:241)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.io.FilterOutputStream.close(FilterOutputStream.java:159)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.io.FilterOutputStream.close(FilterOutputStream.java:159)
[08:54:04] [Spigot Watchdog Thread/ERROR]: net.minecraft.server.v1_8_R3.NBTCompressedStreamTools.a(NBTCompressedStreamTools.java:37)
[08:54:04] [Spigot Watchdog Thread/ERROR]: net.minecraft.server.v1_8_R3.PersistentCollection.a(PersistentCollection.java:101)
[08:54:04] [Spigot Watchdog Thread/ERROR]: net.minecraft.server.v1_8_R3.PersistentCollection.a(PersistentCollection.java:80)
[08:54:04] [Spigot Watchdog Thread/ERROR]: net.minecraft.server.v1_8_R3.WorldServer.a(WorldServer.java:963)
[08:54:04] [Spigot Watchdog Thread/ERROR]: net.minecraft.server.v1_8_R3.WorldServer.save(WorldServer.java:923)
[08:54:04] [Spigot Watchdog Thread/ERROR]: org.bukkit.craftbukkit.v1_8_R3.CraftWorld.save(CraftWorld.java:756)
[08:54:04] [Spigot Watchdog Thread/ERROR]: net.minecraft.server.v1_8_R3.MinecraftServer.A(MinecraftServer.java:682)
[08:54:04] [Spigot Watchdog Thread/ERROR]: net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java:560)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.lang.Thread.run(Thread.java:745)
[08:54:04] [Spigot Watchdog Thread/ERROR]: ------------------------------
[08:54:04] [Spigot Watchdog Thread/ERROR]: Entire Thread Dump:
[08:54:04] [Spigot Watchdog Thread/ERROR]: ------------------------------
[08:54:04] [Spigot Watchdog Thread/ERROR]: Current Thread: process reaper
[08:54:04] [Spigot Watchdog Thread/ERROR]: PID: 297 | Suspended: false | Native: false | State: TIMED_WAITING
[08:54:04] [Spigot Watchdog Thread/ERROR]: Stack:
[08:54:04] [Spigot Watchdog Thread/ERROR]: sun.misc.Unsafe.park(Native Method)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:215)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.SynchronousQueue$TransferStack.awaitFulfill(SynchronousQueue.java:460)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.SynchronousQueue$TransferStack.transfer(SynchronousQueue.java:362)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.SynchronousQueue.poll(SynchronousQueue.java:941)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1066)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1127)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.lang.Thread.run(Thread.java:745)
[08:54:04] [Spigot Watchdog Thread/ERROR]: ------------------------------
[08:54:04] [Spigot Watchdog Thread/ERROR]: Current Thread: Netty Epoll Server IO #3
[08:54:04] [Spigot Watchdog Thread/ERROR]: PID: 39 | Suspended: false | Native: false | State: RUNNABLE
[08:54:04] [Spigot Watchdog Thread/ERROR]: Stack:
[08:54:04] [Spigot Watchdog Thread/ERROR]: io.netty.channel.epoll.Native.epollWait(Native Method)
[08:54:04] [Spigot Watchdog Thread/ERROR]: io.netty.channel.epoll.EpollEventLoop.epollWait(EpollEventLoop.java:194)
[08:54:04] [Spigot Watchdog Thread/ERROR]: io.netty.channel.epoll.EpollEventLoop.run(EpollEventLoop.java:219)
[08:54:04] [Spigot Watchdog Thread/ERROR]: io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:116)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.lang.Thread.run(Thread.java:745)
[08:54:04] [Spigot Watchdog Thread/ERROR]: ------------------------------
[08:54:04] [Spigot Watchdog Thread/ERROR]: Current Thread: Netty Epoll Server IO #2
[08:54:04] [Spigot Watchdog Thread/ERROR]: PID: 38 | Suspended: false | Native: true | State: RUNNABLE
[08:54:04] [Spigot Watchdog Thread/ERROR]: Stack:
[08:54:04] [Spigot Watchdog Thread/ERROR]: io.netty.channel.epoll.Native.epollWait(Native Method)
[08:54:04] [Spigot Watchdog Thread/ERROR]: io.netty.channel.epoll.EpollEventLoop.epollWait(EpollEventLoop.java:194)
[08:54:04] [Spigot Watchdog Thread/ERROR]: io.netty.channel.epoll.EpollEventLoop.run(EpollEventLoop.java:219)
[08:54:04] [Spigot Watchdog Thread/ERROR]: io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:116)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.lang.Thread.run(Thread.java:745)
[08:54:04] [Spigot Watchdog Thread/ERROR]: ------------------------------
[08:54:04] [Spigot Watchdog Thread/ERROR]: Current Thread: Netty Epoll Server IO #1
[08:54:04] [Spigot Watchdog Thread/ERROR]: PID: 37 | Suspended: false | Native: true | State: RUNNABLE
[08:54:04] [Spigot Watchdog Thread/ERROR]: Stack:
[08:54:04] [Spigot Watchdog Thread/ERROR]: io.netty.channel.epoll.Native.epollWait(Native Method)
[08:54:04] [Spigot Watchdog Thread/ERROR]: io.netty.channel.epoll.EpollEventLoop.epollWait(EpollEventLoop.java:194)
[08:54:04] [Spigot Watchdog Thread/ERROR]: io.netty.channel.epoll.EpollEventLoop.run(EpollEventLoop.java:219)
[08:54:04] [Spigot Watchdog Thread/ERROR]: io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:116)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.lang.Thread.run(Thread.java:745)
[08:54:04] [Spigot Watchdog Thread/ERROR]: ------------------------------
[08:54:04] [Spigot Watchdog Thread/ERROR]: Current Thread: pool-12-thread-5
[08:54:04] [Spigot Watchdog Thread/ERROR]: PID: 124 | Suspended: false | Native: false | State: WAITING
[08:54:04] [Spigot Watchdog Thread/ERROR]: Stack:
[08:54:04] [Spigot Watchdog Thread/ERROR]: sun.misc.Unsafe.park(Native Method)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1067)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1127)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.lang.Thread.run(Thread.java:745)
[08:54:04] [Spigot Watchdog Thread/ERROR]: ------------------------------
[08:54:04] [Spigot Watchdog Thread/ERROR]: Current Thread: pool-12-thread-4
[08:54:04] [Spigot Watchdog Thread/ERROR]: PID: 122 | Suspended: false | Native: false | State: WAITING
[08:54:04] [Spigot Watchdog Thread/ERROR]: Stack:
[08:54:04] [Spigot Watchdog Thread/ERROR]: sun.misc.Unsafe.park(Native Method)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1067)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1127)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.lang.Thread.run(Thread.java:745)
[08:54:04] [Spigot Watchdog Thread/ERROR]: ------------------------------
[08:54:04] [Spigot Watchdog Thread/ERROR]: Current Thread: File IO Thread
[08:54:04] [Spigot Watchdog Thread/ERROR]: PID: 116 | Suspended: false | Native: false | State: TIMED_WAITING
[08:54:04] [Spigot Watchdog Thread/ERROR]: Stack:
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.lang.Thread.sleep(Native Method)
[08:54:04] [Spigot Watchdog Thread/ERROR]: net.minecraft.server.v1_8_R3.FileIOThread.c(SourceFile:51)
[08:54:04] [Spigot Watchdog Thread/ERROR]: net.minecraft.server.v1_8_R3.FileIOThread.run(SourceFile:30)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.lang.Thread.run(Thread.java:745)
[08:54:04] [Spigot Watchdog Thread/ERROR]: ------------------------------
[08:54:04] [Spigot Watchdog Thread/ERROR]: Current Thread: pool-12-thread-3
[08:54:04] [Spigot Watchdog Thread/ERROR]: PID: 114 | Suspended: false | Native: false | State: WAITING
[08:54:04] [Spigot Watchdog Thread/ERROR]: Stack:
[08:54:04] [Spigot Watchdog Thread/ERROR]: sun.misc.Unsafe.park(Native Method)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1067)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1127)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.lang.Thread.run(Thread.java:745)
[08:54:04] [Spigot Watchdog Thread/ERROR]: ------------------------------
[08:54:04] [Spigot Watchdog Thread/ERROR]: Current Thread: pool-12-thread-2
[08:54:04] [Spigot Watchdog Thread/ERROR]: PID: 110 | Suspended: false | Native: false | State: WAITING
[08:54:04] [Spigot Watchdog Thread/ERROR]: Stack:
[08:54:04] [Spigot Watchdog Thread/ERROR]: sun.misc.Unsafe.park(Native Method)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1067)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1127)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.lang.Thread.run(Thread.java:745)
[08:54:04] [Spigot Watchdog Thread/ERROR]: ------------------------------
[08:54:04] [Spigot Watchdog Thread/ERROR]: Current Thread: Query Listener #1
[08:54:04] [Spigot Watchdog Thread/ERROR]: PID: 100 | Suspended: false | Native: false | State: RUNNABLE
[08:54:04] [Spigot Watchdog Thread/ERROR]: Thread is waiting on monitor(s):
[08:54:04] [Spigot Watchdog Thread/ERROR]: Locked on:java.net.PlainDatagramSocketImpl.receive0(Native Method)
[08:54:04] [Spigot Watchdog Thread/ERROR]: Locked on:java.net.AbstractPlainDatagramSocketImpl.receive(AbstractPlainDatagramSocketImpl.java:144)
[08:54:04] [Spigot Watchdog Thread/ERROR]: Locked on:java.net.DatagramSocket.receive(DatagramSocket.java:812)
[08:54:04] [Spigot Watchdog Thread/ERROR]: Locked on:java.net.DatagramSocket.receive(DatagramSocket.java:812)
[08:54:04] [Spigot Watchdog Thread/ERROR]: Stack:
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.net.PlainDatagramSocketImpl.receive0(Native Method)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.net.AbstractPlainDatagramSocketImpl.receive(AbstractPlainDatagramSocketImpl.java:144)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.net.DatagramSocket.receive(DatagramSocket.java:812)
[08:54:04] [Spigot Watchdog Thread/ERROR]: net.minecraft.server.v1_8_R3.RemoteStatusListener.run(SourceFile:261)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.lang.Thread.run(Thread.java:745)
[08:54:04] [Spigot Watchdog Thread/ERROR]: ------------------------------
[08:54:04] [Spigot Watchdog Thread/ERROR]: Current Thread: WebsocketSelector99
[08:54:04] [Spigot Watchdog Thread/ERROR]: PID: 99 | Suspended: false | Native: true | State: RUNNABLE
[08:54:04] [Spigot Watchdog Thread/ERROR]: Thread is waiting on monitor(s):
[08:54:04] [Spigot Watchdog Thread/ERROR]: Locked on:sun.nio.ch.SelectorImpl.lockAndDoSelect(SelectorImpl.java:86)
[08:54:04] [Spigot Watchdog Thread/ERROR]: Locked on:sun.nio.ch.SelectorImpl.lockAndDoSelect(SelectorImpl.java:86)
[08:54:04] [Spigot Watchdog Thread/ERROR]: Locked on:sun.nio.ch.SelectorImpl.lockAndDoSelect(SelectorImpl.java:86)
[08:54:04] [Spigot Watchdog Thread/ERROR]: Stack:
[08:54:04] [Spigot Watchdog Thread/ERROR]: sun.nio.ch.EPollArrayWrapper.epollWait(Native Method)
[08:54:04] [Spigot Watchdog Thread/ERROR]: sun.nio.ch.EPollArrayWrapper.poll(EPollArrayWrapper.java:269)
[08:54:04] [Spigot Watchdog Thread/ERROR]: sun.nio.ch.EPollSelectorImpl.doSelect(EPollSelectorImpl.java:79)
[08:54:04] [Spigot Watchdog Thread/ERROR]: sun.nio.ch.SelectorImpl.lockAndDoSelect(SelectorImpl.java:86)
[08:54:04] [Spigot Watchdog Thread/ERROR]: sun.nio.ch.SelectorImpl.select(SelectorImpl.java:97)
[08:54:04] [Spigot Watchdog Thread/ERROR]: sun.nio.ch.SelectorImpl.select(SelectorImpl.java:101)
[08:54:04] [Spigot Watchdog Thread/ERROR]: org.java_websocket.server.WebSocketServer.run(WebSocketServer.java:298)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.lang.Thread.run(Thread.java:745)
[08:54:04] [Spigot Watchdog Thread/ERROR]: ------------------------------
[08:54:04] [Spigot Watchdog Thread/ERROR]: Current Thread: WebSocketWorker-98
[08:54:04] [Spigot Watchdog Thread/ERROR]: PID: 98 | Suspended: false | Native: false | State: WAITING
[08:54:04] [Spigot Watchdog Thread/ERROR]: Stack:
[08:54:04] [Spigot Watchdog Thread/ERROR]: sun.misc.Unsafe.park(Native Method)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
[08:54:04] [Spigot Watchdog Thread/ERROR]: org.java_websocket.server.WebSocketServer$WebSocketWorker.run(WebSocketServer.java:705)
[08:54:04] [Spigot Watchdog Thread/ERROR]: ------------------------------
[08:54:04] [Spigot Watchdog Thread/ERROR]: Current Thread: WebSocketWorker-97
[08:54:04] [Spigot Watchdog Thread/ERROR]: PID: 97 | Suspended: false | Native: false | State: WAITING
[08:54:04] [Spigot Watchdog Thread/ERROR]: Stack:
[08:54:04] [Spigot Watchdog Thread/ERROR]: sun.misc.Unsafe.park(Native Method)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
[08:54:04] [Spigot Watchdog Thread/ERROR]: org.java_websocket.server.WebSocketServer$WebSocketWorker.run(WebSocketServer.java:705)
[08:54:04] [Spigot Watchdog Thread/ERROR]: ------------------------------
[08:54:04] [Spigot Watchdog Thread/ERROR]: Current Thread: WebSocketWorker-96
[08:54:04] [Spigot Watchdog Thread/ERROR]: PID: 96 | Suspended: false | Native: false | State: WAITING
[08:54:04] [Spigot Watchdog Thread/ERROR]: Stack:
[08:54:04] [Spigot Watchdog Thread/ERROR]: sun.misc.Unsafe.park(Native Method)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
[08:54:04] [Spigot Watchdog Thread/ERROR]: org.java_websocket.server.WebSocketServer$WebSocketWorker.run(WebSocketServer.java:705)
[08:54:04] [Spigot Watchdog Thread/ERROR]: ------------------------------
[08:54:04] [Spigot Watchdog Thread/ERROR]: Current Thread: WebSocketWorker-95
[08:54:04] [Spigot Watchdog Thread/ERROR]: PID: 95 | Suspended: false | Native: false | State: WAITING
[08:54:04] [Spigot Watchdog Thread/ERROR]: Stack:
[08:54:04] [Spigot Watchdog Thread/ERROR]: sun.misc.Unsafe.park(Native Method)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
[08:54:04] [Spigot Watchdog Thread/ERROR]: org.java_websocket.server.WebSocketServer$WebSocketWorker.run(WebSocketServer.java:705)
[08:54:04] [Spigot Watchdog Thread/ERROR]: ------------------------------
[08:54:04] [Spigot Watchdog Thread/ERROR]: Current Thread: WebSocketWorker-94
[08:54:04] [Spigot Watchdog Thread/ERROR]: PID: 94 | Suspended: false | Native: false | State: WAITING
[08:54:04] [Spigot Watchdog Thread/ERROR]: Stack:
[08:54:04] [Spigot Watchdog Thread/ERROR]: sun.misc.Unsafe.park(Native Method)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
[08:54:04] [Spigot Watchdog Thread/ERROR]: org.java_websocket.server.WebSocketServer$WebSocketWorker.run(WebSocketServer.java:705)
[08:54:04] [Spigot Watchdog Thread/ERROR]: ------------------------------
[08:54:04] [Spigot Watchdog Thread/ERROR]: Current Thread: WebSocketWorker-93
[08:54:04] [Spigot Watchdog Thread/ERROR]: PID: 93 | Suspended: false | Native: false | State: WAITING
[08:54:04] [Spigot Watchdog Thread/ERROR]: Stack:
[08:54:04] [Spigot Watchdog Thread/ERROR]: sun.misc.Unsafe.park(Native Method)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
[08:54:04] [Spigot Watchdog Thread/ERROR]: org.java_websocket.server.WebSocketServer$WebSocketWorker.run(WebSocketServer.java:705)
[08:54:04] [Spigot Watchdog Thread/ERROR]: ------------------------------
[08:54:04] [Spigot Watchdog Thread/ERROR]: Current Thread: WebSocketWorker-92
[08:54:04] [Spigot Watchdog Thread/ERROR]: PID: 92 | Suspended: false | Native: false | State: WAITING
[08:54:04] [Spigot Watchdog Thread/ERROR]: Stack:
[08:54:04] [Spigot Watchdog Thread/ERROR]: sun.misc.Unsafe.park(Native Method)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
[08:54:04] [Spigot Watchdog Thread/ERROR]: org.java_websocket.server.WebSocketServer$WebSocketWorker.run(WebSocketServer.java:705)
[08:54:04] [Spigot Watchdog Thread/ERROR]: ------------------------------
[08:54:04] [Spigot Watchdog Thread/ERROR]: Current Thread: WebSocketWorker-91
[08:54:04] [Spigot Watchdog Thread/ERROR]: PID: 91 | Suspended: false | Native: false | State: WAITING
[08:54:04] [Spigot Watchdog Thread/ERROR]: Stack:
[08:54:04] [Spigot Watchdog Thread/ERROR]: sun.misc.Unsafe.park(Native Method)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
[08:54:04] [Spigot Watchdog Thread/ERROR]: org.java_websocket.server.WebSocketServer$WebSocketWorker.run(WebSocketServer.java:705)
[08:54:04] [Spigot Watchdog Thread/ERROR]: ------------------------------
[08:54:04] [Spigot Watchdog Thread/ERROR]: Current Thread: WebSocketWorker-90
[08:54:04] [Spigot Watchdog Thread/ERROR]: PID: 90 | Suspended: false | Native: false | State: WAITING
[08:54:04] [Spigot Watchdog Thread/ERROR]: Stack:
[08:54:04] [Spigot Watchdog Thread/ERROR]: sun.misc.Unsafe.park(Native Method)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
[08:54:04] [Spigot Watchdog Thread/ERROR]: org.java_websocket.server.WebSocketServer$WebSocketWorker.run(WebSocketServer.java:705)
[08:54:04] [Spigot Watchdog Thread/ERROR]: ------------------------------
[08:54:04] [Spigot Watchdog Thread/ERROR]: Current Thread: WebSocketWorker-89
[08:54:04] [Spigot Watchdog Thread/ERROR]: PID: 89 | Suspended: false | Native: false | State: WAITING
[08:54:04] [Spigot Watchdog Thread/ERROR]: Stack:
[08:54:04] [Spigot Watchdog Thread/ERROR]: sun.misc.Unsafe.park(Native Method)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
[08:54:04] [Spigot Watchdog Thread/ERROR]: org.java_websocket.server.WebSocketServer$WebSocketWorker.run(WebSocketServer.java:705)
[08:54:04] [Spigot Watchdog Thread/ERROR]: ------------------------------
[08:54:04] [Spigot Watchdog Thread/ERROR]: Current Thread: WebSocketWorker-88
[08:54:04] [Spigot Watchdog Thread/ERROR]: PID: 88 | Suspended: false | Native: false | State: WAITING
[08:54:04] [Spigot Watchdog Thread/ERROR]: Stack:
[08:54:04] [Spigot Watchdog Thread/ERROR]: sun.misc.Unsafe.park(Native Method)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
[08:54:04] [Spigot Watchdog Thread/ERROR]: org.java_websocket.server.WebSocketServer$WebSocketWorker.run(WebSocketServer.java:705)
[08:54:04] [Spigot Watchdog Thread/ERROR]: ------------------------------
[08:54:04] [Spigot Watchdog Thread/ERROR]: Current Thread: WebSocketWorker-87
[08:54:04] [Spigot Watchdog Thread/ERROR]: PID: 87 | Suspended: false | Native: false | State: WAITING
[08:54:04] [Spigot Watchdog Thread/ERROR]: Stack:
[08:54:04] [Spigot Watchdog Thread/ERROR]: sun.misc.Unsafe.park(Native Method)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
[08:54:04] [Spigot Watchdog Thread/ERROR]: org.java_websocket.server.WebSocketServer$WebSocketWorker.run(WebSocketServer.java:705)
[08:54:04] [Spigot Watchdog Thread/ERROR]: ------------------------------
[08:54:04] [Spigot Watchdog Thread/ERROR]: Current Thread: WebSocketWorker-86
[08:54:04] [Spigot Watchdog Thread/ERROR]: PID: 86 | Suspended: false | Native: false | State: WAITING
[08:54:04] [Spigot Watchdog Thread/ERROR]: Stack:
[08:54:04] [Spigot Watchdog Thread/ERROR]: sun.misc.Unsafe.park(Native Method)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
[08:54:04] [Spigot Watchdog Thread/ERROR]: org.java_websocket.server.WebSocketServer$WebSocketWorker.run(WebSocketServer.java:705)
[08:54:04] [Spigot Watchdog Thread/ERROR]: ------------------------------
[08:54:04] [Spigot Watchdog Thread/ERROR]: Current Thread: WebSocketWorker-85
[08:54:04] [Spigot Watchdog Thread/ERROR]: PID: 85 | Suspended: false | Native: false | State: WAITING
[08:54:04] [Spigot Watchdog Thread/ERROR]: Stack:
[08:54:04] [Spigot Watchdog Thread/ERROR]: sun.misc.Unsafe.park(Native Method)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
[08:54:04] [Spigot Watchdog Thread/ERROR]: org.java_websocket.server.WebSocketServer$WebSocketWorker.run(WebSocketServer.java:705)
[08:54:04] [Spigot Watchdog Thread/ERROR]: ------------------------------
[08:54:04] [Spigot Watchdog Thread/ERROR]: Current Thread: WebSocketWorker-84
[08:54:04] [Spigot Watchdog Thread/ERROR]: PID: 84 | Suspended: false | Native: false | State: WAITING
[08:54:04] [Spigot Watchdog Thread/ERROR]: Stack:
[08:54:04] [Spigot Watchdog Thread/ERROR]: sun.misc.Unsafe.park(Native Method)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
[08:54:04] [Spigot Watchdog Thread/ERROR]: org.java_websocket.server.WebSocketServer$WebSocketWorker.run(WebSocketServer.java:705)
[08:54:04] [Spigot Watchdog Thread/ERROR]: ------------------------------
[08:54:04] [Spigot Watchdog Thread/ERROR]: Current Thread: WebSocketWorker-83
[08:54:04] [Spigot Watchdog Thread/ERROR]: PID: 83 | Suspended: false | Native: false | State: WAITING
[08:54:04] [Spigot Watchdog Thread/ERROR]: Stack:
[08:54:04] [Spigot Watchdog Thread/ERROR]: sun.misc.Unsafe.park(Native Method)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
[08:54:04] [Spigot Watchdog Thread/ERROR]: org.java_websocket.server.WebSocketServer$WebSocketWorker.run(WebSocketServer.java:705)
[08:54:04] [Spigot Watchdog Thread/ERROR]: ------------------------------
[08:54:04] [Spigot Watchdog Thread/ERROR]: Current Thread: WebSocketWorker-82
[08:54:04] [Spigot Watchdog Thread/ERROR]: PID: 82 | Suspended: false | Native: false | State: WAITING
[08:54:04] [Spigot Watchdog Thread/ERROR]: Stack:
[08:54:04] [Spigot Watchdog Thread/ERROR]: sun.misc.Unsafe.park(Native Method)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
[08:54:04] [Spigot Watchdog Thread/ERROR]: java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)

You can find the full error here (because it's too many long)
http://pastebin.com/jK2DiNEj