---- Minecraft Crash Report ----
// Oops.

Time: 7/7/18 2:32 PM
Description: Exception generating new chunk

java.util.concurrent.ExecutionException: java.lang.ClassCastException: bbj cannot be cast to bcw
at java.util.concurrent.CompletableFuture.reportGet(CompletableFuture.java:357)
at java.util.concurrent.CompletableFuture.get(CompletableFuture.java:1887)
at sy.c(SourceFile:126)
at tg.a(SourceFile:85)
at th.c(SourceFile:123)
at sz.i_(SourceFile:219)
at net.minecraft.server.MinecraftServer.w(SourceFile:690)
at net.minecraft.server.MinecraftServer.v(SourceFile:623)
at dfa.v(SourceFile:155)
at net.minecraft.server.MinecraftServer.run(SourceFile:525)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.ClassCastException: bbj cannot be cast to bcw
at bwj$c.a(SourceFile:1884)
at bwe.a(SourceFile:60)
at bsm.a(SourceFile:77)
at bus.a(SourceFile:16)
at bus.a(SourceFile:13)
at boo.a(SourceFile:27)
at aya.a(SourceFile:516)
at bma.a(SourceFile:109)
at tn.a(SourceFile:12)
at tm.a(SourceFile:35)
at bme.a(SourceFile:95)
at tt.a(SourceFile:62)
at tt.a(SourceFile:25)
at ach$a.a(SourceFile:130)
at ach$a$$Lambda$1810/1722910240.apply(Unknown Source)
at java.util.concurrent.CompletableFuture.uniApply(CompletableFuture.java:602)
at java.util.concurrent.CompletableFuture$UniApply.tryFire(CompletableFuture.java:577)
at java.util.concurrent.CompletableFuture$Completion.exec(CompletableFuture.java:443)
at java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:289)
at java.util.concurrent.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1056)
at java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1689)
at java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:157)

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

– Head –
Thread: Server thread
Stacktrace:
at java.util.concurrent.CompletableFuture.reportGet(CompletableFuture.java:357)

– Chunk to be generated –
Details:
Location: -30,34
Position hash: 150323855330
Generator: bnw@5d0c02af
Stacktrace:
at sy.a(SourceFile:170)
at sy.c(SourceFile:129)
at tg.a(SourceFile:85)
at th.c(SourceFile:123)
at sz.i_(SourceFile:219)
at net.minecraft.server.MinecraftServer.w(SourceFile:690)
at net.minecraft.server.MinecraftServer.v(SourceFile:623)
at dfa.v(SourceFile:155)
at net.minecraft.server.MinecraftServer.run(SourceFile:525)
at java.lang.Thread.run(Thread.java:745)

– Affected level –
Details:
Level name: Chaddland_210
All players: 1 total; [tb['TheChadio210'/237, l='Chaddland_210', x=-493.85, y=72.00, z=354.38]]
Chunk stats: ServerChunkCache: 1246 Drop: 0
Level seed: -1384790610146769960
Level generator: ID 00 - default, ver 1. Features enabled: true
Level generator options: {}
Level spawn location: World: (152,64,244), Chunk: (at 8,4,4 in 9,15; contains blocks 144,0,240 to 159,255,255), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
Level time: 7713533 game time, 7850309 day time
Level dimension: 0
Level storage version: 0x04ABD - Anvil
Level weather: Rain time: 27458 (now: false), thunder time: 38686 (now: false)
Level game mode: Game mode: survival (ID 0). Hardcore: false. Cheats: false

– System Details –
Details:
Minecraft Version: 1.13-pre6
Operating System: Windows 10 (amd64) version 10.0
Java Version: 1.8.0_51, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 333872312 bytes (318 MB) / 738197504 bytes (704 MB) up to 1073741824 bytes (1024 MB)
JVM Flags: 9 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xss1M -Xmx1G -XX:+UnlockExperimentalVMOptions -XX:+UseG1GC -XX:G1NewSizePercent=20 -XX:G1ReservePercent=20 -XX:MaxGCPauseMillis=50 -XX:G1HeapRegionSize=16M
Profiler Position: N/A (disabled)
Player Count: 1 / 8; [tb['TheChadio210'/237, l='Chaddland_210', x=-493.85, y=72.00, z=354.38]]
Data Packs: vanilla
Type: Integrated Server (map_client.txt)
Is Modded: Probably not. Jar signature remains and both client + server brands are untouched.