[1.7.10] NetworkDispatcher exception - Anyone know where this could come from?

[Thornack]

This happens when I run a dedicated server, join the world, then store an entity inside my itemstack using my item and pick up the resultant item containing the nbt data for my entity "too fast" it seems (although it doesnt happen every time which is odd) Anyone know why this would occur?

[13:57:03] [Netty IO #2/ERROR] [FML]: NetworkDispatcher exception
io.netty.handler.codec.EncoderException: java.util.ConcurrentModificationException
at io.netty.handler.codec.MessageToByteEncoder.write(MessageToByteEncoder.java:129) ~[MessageToByteEncoder.class:?]
at io.netty.channel.DefaultChannelHandlerContext.invokeWrite(DefaultChannelHandlerContext.java:644) ~[DefaultChannelHandlerContext.class:?]
at io.netty.channel.DefaultChannelHandlerContext.write(DefaultChannelHandlerContext.java:698) ~[DefaultChannelHandlerContext.class:?]
at io.netty.channel.DefaultChannelHandlerContext.write(DefaultChannelHandlerContext.java:637) ~[DefaultChannelHandlerContext.class:?]
at cpw.mods.fml.common.network.handshake.NetworkDispatcher.write(NetworkDispatcher.java:423) ~[NetworkDispatcher.class:?]
at io.netty.channel.DefaultChannelHandlerContext.invokeWrite(DefaultChannelHandlerContext.java:644) ~[DefaultChannelHandlerContext.class:?]
at io.netty.channel.DefaultChannelHandlerContext.write(DefaultChannelHandlerContext.java:698) ~[DefaultChannelHandlerContext.class:?]
at io.netty.channel.DefaultChannelHandlerContext.writeAndFlush(DefaultChannelHandlerContext.java:688) ~[DefaultChannelHandlerContext.class:?]
at io.netty.channel.DefaultChannelHandlerContext.writeAndFlush(DefaultChannelHandlerContext.java:717) ~[DefaultChannelHandlerContext.class:?]
at io.netty.channel.DefaultChannelPipeline.writeAndFlush(DefaultChannelPipeline.java:893) ~[DefaultChannelPipeline.class:?]
at io.netty.channel.AbstractChannel.writeAndFlush(AbstractChannel.java:239) ~[AbstractChannel.class:?]
at net.minecraft.network.NetworkManager$1.run(NetworkManager.java:197) [NetworkManager$1.class:?]
at io.netty.util.concurrent.SingleThreadEventExecutor.runAllTasks(SingleThreadEventExecutor.java:354) [singleThreadEventExecutor.class:?]
at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:348) [NioEventLoop.class:?]
at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:101) [singleThreadEventExecutor$2.class:?]
at java.lang.Thread.run(Unknown Source) [?:1.7.0_25]
Caused by: java.util.ConcurrentModificationException
at java.util.HashMap$HashIterator.nextEntry(Unknown Source) ~[?:1.7.0_25]
at java.util.HashMap$KeyIterator.next(Unknown Source) ~[?:1.7.0_25]
at net.minecraft.nbt.NBTTagCompound.write(NBTTagCompound.java:33) ~[NBTTagCompound.class:?]
at net.minecraft.nbt.CompressedStreamTools.func_150663_a(CompressedStreamTools.java:158) ~[CompressedStreamTools.class:?]
at net.minecraft.nbt.CompressedStreamTools.write(CompressedStreamTools.java:148) ~[CompressedStreamTools.class:?]
at net.minecraft.nbt.CompressedStreamTools.compress(CompressedStreamTools.java:88) ~[CompressedStreamTools.class:?]
at net.minecraft.network.PacketBuffer.writeNBTTagCompoundToBuffer(PacketBuffer.java:94) ~[PacketBuffer.class:?]
at net.minecraft.network.PacketBuffer.writeItemStackToBuffer(PacketBuffer.java:140) ~[PacketBuffer.class:?]
at net.minecraft.entity.DataWatcher.writeWatchableObjectToPacketBuffer(DataWatcher.java:289) ~[DataWatcher.class:?]
at net.minecraft.entity.DataWatcher.writeWatchedListToPacketBuffer(DataWatcher.java:186) ~[DataWatcher.class:?]
at net.minecraft.network.play.server.S1CPacketEntityMetadata.writePacketData(S1CPacketEntityMetadata.java:50) ~[s1CPacketEntityMetadata.class:?]
at net.minecraft.util.MessageSerializer.encode(MessageSerializer.java:46) ~[MessageSerializer.class:?]
at net.minecraft.util.MessageSerializer.encode(MessageSerializer.java:53) ~[MessageSerializer.class:?]
at io.netty.handler.codec.MessageToByteEncoder.write(MessageToByteEncoder.java:111) ~[MessageToByteEncoder.class:?]
... 15 more
[13:57:03] [server thread/INFO]: Player14 lost connection: TranslatableComponent{key='disconnect.genericReason', args=[internal Exception: io.netty.handler.codec.EncoderException: java.util.ConcurrentModificationException], siblings=[], style=Style{hasParent=false, color=null, bold=null, italic=null, underlined=null, obfuscated=null, clickEvent=null, hoverEvent=null}}
[13:57:03] [server thread/INFO]: Player14 left the game

 

[Ernio]

You are fking with threads. Something from somewhere (thread) is editing something it is not supposed to.

 

What did you do... (this time) ? (code)

[Thornack]

I think I can bandaid the solution by setting the delayBeforeCanPickup variable for the entity item (somehow) but i think id rather know what the real issue is so i can fix it

[Thornack]

any idea where to start debugging this?

[Thornack]

I have no idea where to even look the error only happens once in a while it seems so Im not sure what code to provide

 

[Ernio]

How about update to 1.9 (finally) and rewrite stuff to proper main<->network thread handling.

1.7.10 is ancient and networking changed enough for most of us to simply not be able to help.

 

Anywaya:

No, I have no idea and you must be doing something REALLY weird. If you are not using any of your own packets, it must be some kind of return you do or something else.

 

For one I'd be interested in "and pick up the resultant item" - what do you mean? Do you use item, catch entity and then pick it up or what?

 

Again: code (and yeah, I know it is big and super messy, so only github is accepted in this case).

 

I have no idea where to even look the error only happens once in a while it seems so Im not sure what code to provide

Because that is what messing with threads do.

[Thornack]

kk ill get my code to github and post a link asap