Problem/Bug Exception ticking world

My server continues to crash on a regular basis.
This seems to be a problem with the world, and if so, I would like to know what possible fixes there are beyond simply deleting the world. I have used NBTEditor to change player locations, and this has worked for a short time, but inevitably the server crashes.
FYI: I am using MCPro Hosting, Bukkit API version 1.11.2-R0.1-SNAPSHOT

Code:

01.06 16:52:55 [Disconnect] User Brownie_Bit has disconnected, reason: Server closed
01.06 16:52:55 [Server] INFO Saving players
01.06 16:52:55 [Server] INFO Stopping server
01.06 16:52:55 [Server] ERROR This crash report has been saved to: /./crash-reports/crash-2017-06-01_16.52.55-server.txt
01.06 16:52:55 [Server] INFO ... 4 more
01.06 16:52:55 [Server] INFO at net.minecraft.server.v1_11_R1.MinecraftServer.D(MinecraftServer.java:739) ~[CraftBukkit.jar:git-Bukkit-6e3cec8]
01.06 16:52:55 [Server] INFO at net.minecraft.server.v1_11_R1.WorldServer.doTick(WorldServer.java:248) ~[CraftBukkit.jar:git-Bukkit-6e3cec8]
01.06 16:52:55 [Server] INFO at net.minecraft.server.v1_11_R1.WorldServer.j(WorldServer.java:473) ~[CraftBukkit.jar:git-Bukkit-6e3cec8]
01.06 16:52:55 [Server] INFO at net.minecraft.server.v1_11_R1.Block.a(Block.java:295) ~[CraftBukkit.jar:git-Bukkit-6e3cec8]
01.06 16:52:55 [Server] INFO at net.minecraft.server.v1_11_R1.BlockGrass.b(BlockGrass.java:32) ~[CraftBukkit.jar:git-Bukkit-6e3cec8]
01.06 16:52:55 [Server] INFO at net.minecraft.server.v1_11_R1.World.getLightLevel(World.java:630) ~[CraftBukkit.jar:git-Bukkit-6e3cec8]
01.06 16:52:55 [Server] INFO at net.minecraft.server.v1_11_R1.World.c(World.java:639) ~[CraftBukkit.jar:git-Bukkit-6e3cec8]
01.06 16:52:55 [Server] INFO at net.minecraft.server.v1_11_R1.World.c(World.java:668) ~[CraftBukkit.jar:git-Bukkit-6e3cec8]
01.06 16:52:55 [Server] INFO Caused by: java.lang.NullPointerException
01.06 16:52:55 [Server] INFO at java.lang.Thread.run(Unknown Source) [?:1.8.0_131]
01.06 16:52:55 [Server] INFO at net.minecraft.server.v1_11_R1.MinecraftServer.run(MinecraftServer.java:554) [CraftBukkit.jar:git-Bukkit-6e3cec8]
01.06 16:52:55 [Server] INFO at net.minecraft.server.v1_11_R1.MinecraftServer.C(MinecraftServer.java:650) ~[CraftBukkit.jar:git-Bukkit-6e3cec8]
01.06 16:52:55 [Server] INFO at net.minecraft.server.v1_11_R1.DedicatedServer.D(DedicatedServer.java:360) ~[CraftBukkit.jar:git-Bukkit-6e3cec8]
01.06 16:52:55 [Server] INFO at net.minecraft.server.v1_11_R1.MinecraftServer.D(MinecraftServer.java:743) ~[CraftBukkit.jar:git-Bukkit-6e3cec8]
01.06 16:52:55 [Server] INFO net.minecraft.server.v1_11_R1.ReportedException: Exception ticking world
01.06 16:52:55 [Server] ERROR Encountered an unexpected exception
01.06 16:52:31 [Multicraft] Brownie_Bit ran command Message of the Day

 

@JohnEMcCarthy
Have you reported this to spigot? This is a problem with their code for that version. Post the full error log along with all reverent information on the issue forum:
https://hub.spigotmc.org/jira/secure/Dashboard.jspa

 

I haven't. I am at the Create Issue page now.
Could you explain what the problem is, more specifically what "Project" I should post it with?

 

@JohnEMcCarthy
This is a problem with Spigot, as this has nothing to do with any plugins installed.

The problem seems to be that something is null on line 739 of the MinecraftServer class. Since I don't think the file itself is corrupt, spigot most likely forgot/didn't think to add a check for one of the variables on that line, and 'should' be a simple fix.