I really need help with this, I have no idea what to do.
java.lang.ArrayIndexOutOfBoundsException: -7342273
at java.util.ArrayList.elementData(ArrayList.java:418)
at java.util.ArrayList.set(ArrayList.java:446)
at net.minecraft.world.chunk.storage.RegionFile.<init>(RegionFile.java:94)
at net.minecraft.world.chunk.storage.RegionFileCache.func_76550_a(SourceFile:64)
at net.minecraft.world.chunk.storage.RegionFileCache.func_76549_c(SourceFile:110)
at net.minecraft.world.chunk.storage.AnvilChunkLoader.loadChunk__Async(AnvilChunkLoader.java:82)
at net.minecraftforge.common.chunkio.ChunkIOProvider.run(ChunkIOProvider.java:70)
at net.minecraftforge.common.chunkio.ChunkIOExecutor.syncChunkLoad(ChunkIOExecutor.java:92)
at net.minecraft.world.gen.ChunkProviderServer.loadChunk(ChunkProviderServer.java:118)
at net.minecraft.world.gen.ChunkProviderServer.func_186028_c(ChunkProviderServer.java:89)
at net.minecraft.world.gen.ChunkProviderServer.func_186025_d(ChunkProviderServer.java:135)
at net.minecraft.world.World.func_72964_e(World.java:310)
at net.minecraft.world.World.func_72838_d(World.java:1211)
at net.minecraft.world.WorldServer.func_72838_d(WorldServer.java:1058)
at net.minecraft.server.management.PlayerList.func_72377_c(PlayerList.java:377)
at net.minecraft.server.management.PlayerList.initializeConnectionToPlayer(PlayerList.java:166)
at net.minecraftforge.fml.common.network.handshake.NetworkDispatcher.completeServerSideConnection(NetworkDispatcher.java:255)
at net.minecraftforge.fml.common.network.handshake.NetworkDispatcher.access$100(NetworkDispatcher.java:72)
at net.minecraftforge.fml.common.network.handshake.NetworkDispatcher$1.func_73660_a(NetworkDispatcher.java:205)
at net.minecraft.network.NetworkManager.func_74428_b(NetworkManager.java:285)
at net.minecraft.network.NetworkSystem.func_151269_c(NetworkSystem.java:180)
at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:790)
at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:668)
at net.minecraft.server.integrated.IntegratedServer.func_71217_p(IntegratedServer.java:279)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:526)
at java.lang.Thread.run(Thread.java:745)