[13:53:51] [Server thread/INFO]: Starting minecraft server version 1.12.2
[13:53:51] [Server thread/INFO]: Loading properties
[13:53:51] [Server thread/INFO]: Default game type: SURVIVAL
[13:53:51] [Server thread/INFO]: Generating keypair
[13:53:52] [Server thread/INFO]: Starting Minecraft server on 0.0.0.0:27083
[13:53:52] [Server thread/INFO]: Using epoll channel type
[13:53:52] [Server thread/INFO]: This server is running CraftBukkit version git-Bukkit-acbc348 (MC: 1.12.2) (Implementing API version 1.12.2-R0.1-SNAPSHOT)
[13:53:52] [Server thread/INFO]: Preparing level "world"
[13:53:52] [Server thread/WARN]: java.io.FileNotFoundException: ./world/session.lock (Not a directory)
[13:53:52] [Server thread/WARN]:    at java.io.FileOutputStream.open0(Native Method)
[13:53:52] [Server thread/WARN]:    at java.io.FileOutputStream.open(FileOutputStream.java:270)
[13:53:52] [Server thread/WARN]:    at java.io.FileOutputStream.<init>(FileOutputStream.java:213)
[13:53:52] [Server thread/WARN]:    at java.io.FileOutputStream.<init>(FileOutputStream.java:162)
[13:53:52] [Server thread/WARN]:    at net.minecraft.server.v1_12_R1.WorldNBTStorage.i(WorldNBTStorage.java:53)
[13:53:52] [Server thread/WARN]:    at net.minecraft.server.v1_12_R1.WorldNBTStorage.<init>(WorldNBTStorage.java:47)
[13:53:52] [Server thread/WARN]:    at net.minecraft.server.v1_12_R1.ServerNBTManager.<init>(SourceFile:21)
[13:53:52] [Server thread/WARN]:    at net.minecraft.server.v1_12_R1.MinecraftServer.a(MinecraftServer.java:255)
[13:53:52] [Server thread/WARN]:    at net.minecraft.server.v1_12_R1.DedicatedServer.init(DedicatedServer.java:248)
[13:53:52] [Server thread/WARN]:    at net.minecraft.server.v1_12_R1.MinecraftServer.run(MinecraftServer.java:522)
[13:53:52] [Server thread/WARN]:    at java.lang.Thread.run(Thread.java:748)
[13:53:52] [Server thread/ERROR]: Encountered an unexpected exception
java.lang.RuntimeException: Failed to check session lock, aborting
    at net.minecraft.server.v1_12_R1.WorldNBTStorage.i(WorldNBTStorage.java:63) ~[server.jar:git-Bukkit-acbc348]
    at net.minecraft.server.v1_12_R1.WorldNBTStorage.<init>(WorldNBTStorage.java:47) ~[server.jar:git-Bukkit-acbc348]
    at net.minecraft.server.v1_12_R1.ServerNBTManager.<init>(SourceFile:21) ~[server.jar:git-Bukkit-acbc348]
    at net.minecraft.server.v1_12_R1.MinecraftServer.a(MinecraftServer.java:255) ~[server.jar:git-Bukkit-acbc348]
    at net.minecraft.server.v1_12_R1.DedicatedServer.init(DedicatedServer.java:248) ~[server.jar:git-Bukkit-acbc348]
    at net.minecraft.server.v1_12_R1.MinecraftServer.run(MinecraftServer.java:522) [server.jar:git-Bukkit-acbc348]
    at java.lang.Thread.run(Thread.java:748) [?:1.8.0_212]
[13:53:52] [Server thread/ERROR]: This crash report has been saved to: /home/container/./crash-reports/crash-2019-09-21_13.53.52-server.txt
[13:53:52] [Server thread/INFO]: Stopping server
[13:53:52] [Server thread/INFO]: Saving players
[13:53:52] [Server thread/INFO]: Saving worlds