Constantly Crashing

Minecraft Crash Report ----
// I feel sad now 😞

Time: 15/06/18 18:55
Description: Exception generating new chunk

java.util.concurrent.ExecutionException: java.lang.OutOfMemoryError: Java heap space
at java.util.concurrent.CompletableFuture.get(CompletableFuture.java:2237)
at sm.c(SourceFile:126)
at su.a(SourceFile:84)
at sv.c(SourceFile:143)
at sn.i_(SourceFile:223)
at net.minecraft.server.MinecraftServer.w(SourceFile:693)
at net.minecraft.server.MinecraftServer.v(SourceFile:626)
at dir.v(SourceFile:156)
at net.minecraft.server.MinecraftServer.run(SourceFile:531)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.OutOfMemoryError: Java heap space
at it.unimi.dsi.fastutil.ints.IntArrayFIFOQueue.resize(IntArrayFIFOQueue.java:175)
at it.unimi.dsi.fastutil.ints.IntArrayFIFOQueue.expand(IntArrayFIFOQueue.java:189)
at it.unimi.dsi.fastutil.ints.IntArrayFIFOQueue.enqueue(IntArrayFIFOQueue.java:201)
at cbt.a(SourceFile:138)
at cbt.a(SourceFile:142)
at cbt.a(SourceFile:126)
at cbu.a(SourceFile:20)
at te.a(SourceFile:23)
at ta.a(SourceFile:35)
at bqi.a(SourceFile:95)
at th.a(SourceFile:61)
at th.a(SourceFile:24)
at agl$a.a(SourceFile:131)
at agl$a$$Lambda$1537/192887866.apply(Unknown Source)
at java.util.concurrent.CompletableFuture$AsyncApply.exec(CompletableFuture.java:501)
at java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:289)
at java.util.concurrent.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:902)
at java.util.concurrent.ForkJoinPool.scan(ForkJoinPool.java:1689)
at java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1644)
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: Client thread
Stacktrace:
at sm.a(SourceFile:170)

-- Chunk to be generated --
Details:
Location: -13,69
Position hash: 300647710707
Generator: bsa@3dabe8c6
Stacktrace:
at sm.a(SourceFile:170)
at sm.c(SourceFile:129)
at su.a(SourceFile:84)
at sv.c(SourceFile:143)
at sn.i_(SourceFile:223)
at net.minecraft.server.MinecraftServer.w(SourceFile:693)
at net.minecraft.server.MinecraftServer.v(SourceFile:626)
at dir.v(SourceFile:156)
at net.minecraft.server.MinecraftServer.run(SourceFile:531)
at java.lang.Thread.run(Thread.java:745)

-- Affected level --
Details:
Level name: My Chemical Death
All players: 1 total; [sp['jaffacraft1'/142, l='My Chemical Death', x=-182.30, y=65.00, z=1210.30]]
Chunk stats: ServerChunkCache: 808 Drop: 0
Level seed: -630968554
Level generator: ID 02 - largeBiomes, ver 0. Features enabled: true
Level generator options: null
Level spawn location: World: (248,64,477), Chunk: (at 8,4,13 in 15,29; contains blocks 240,0,464 to 255,255,479), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
Level time: 2552412 game time, 62958 day time
Level dimension: 0
Level storage version: 0x04ABD - Anvil
Level weather: Rain time: 119833 (now: false), thunder time: 73507 (now: false)
Level game mode: Game mode: survival (ID 0). Hardcore: false. Cheats: false