I got the the first connection to work!! The server now accepts the client joining the server, and the player is really in world joined on the server! (it gets kicked after a while for not responding to more packets). it was really hard to get the decode and encode and all the Minecraft special types like VarInt to work, but they work now! next I will be trying to make it threaded, add the first gui, also I need to implement like 300 more packets fore the client but at the moment only some are importent so yeaa!