Ok so I have a program where the server has a hashmap storing all of the players mana and every tick it send the data to all players via networking.

I'm trying to make an item that when right clicked it uses some of the mana i have stored, in the hashmap I use the ServerPlayer as the key but when I try and cast a regular player to serverplayer:

public static boolean useMana(Player _player, float mana) { ServerPlayer player = (ServerPlayer) _player;

it throws the error:

java.lang.ClassCastException: class net.minecraft.client.player.LocalPlayer cannot be cast to class net.minecraft.server.level.ServerPlayer (net.minecraft.client.player.LocalPlayer and net.minecraft.server.level.ServerPlayer are in module [email protected] of loader 'TRANSFORMER' @3dd31157)

thanks in advance for any help
 

First, and this is more of a helpful aside, you shouldn't be sending the mana every tick. You should only send mana updates when the player first connects, and when the value changes, to minimize network traffic and the impact of your mod on server performance.

As for the error, this simply means that wherever you're calling useMana from is passing in a player from the client side, instead of the server side. Either you need to ensure that the side calling useMana is the server, or you should include the code that's calling useMana.

yeah i figured it out, ty anyway