I'm trying to unregister a command I'd previously registered with the CommandDispatcher using something like

private static int registerAlias(CommandDispatcher<CommandSourceStack> dispatcher, String alias, String command) {
	dispatcher.register(Commands.literal(alias)
		.executes((commandContext) -> {
			dispatcher.execute(command, commandContext.getSource());
			return Command.SINGLE_SUCCESS;
		})
	);
	return Command.SINGLE_SUCCESS;
}

The dispatcher doesn't seem to have an unregister method. The closest I found was the removeCommand method here, but that seems to be a Bukkit thing. So I tried another solution that does something similar with reflection:

@SuppressWarnings("unchecked")
private static int unregisterAlias(CommandDispatcher<CommandSourceStack> dispatcher, String alias) {
	Object node = dispatcher.getRoot().getChild(alias);
	if (node != null) {
		try {
			if (node instanceof LiteralCommandNode<?>) {
				Field literals = CommandNode.class.getDeclaredField("literals");
				literals.setAccessible(true);
				((Map<String, ?>) literals.get(node)).remove(alias, node);
			} else if (node instanceof ArgumentCommandNode<?, ?>) {
				Field arguments = CommandNode.class.getDeclaredField("arguments");
				arguments.setAccessible(true);
				((Map<String, ?>) arguments.get(node)).remove(alias, node);
			}
			Field children = CommandNode.class.getDeclaredField("children");
			children.setAccessible(true);
			((Map<String, ?>) children.get(node)).remove(alias, node);
		} catch (ReflectiveOperationException e) {
			throw new RuntimeException("Error removing command: " + alias, e);
		}
	}
	return Command.SINGLE_SUCCESS;
}

However, this didn't work. The method was executed without errors (I checked with the Debugger), but the command was still working ingame, meaning it wasn't actually removed from the dispatcher. How would I actually remove a registered command from a CommandDispatcher?

Edited March 8, 20232 yr by Frozen Storm
Resolved

What the heck are you trying to do? If you want to remove a command that you added, just remove or comment out the code that registers that command! If you are trying to completely remove a command during runtime, that is probably impossible.

Edited March 3, 20232 yr by Hipposgrumm

Yes, I'm trying to remove a command during runtime. The command is added (registered) either at game start or during runtime with the registerAlias method, and I'd like to be able to remove it without having to restart the game.

Edited March 3, 20232 yr by Frozen Storm

I managed to accomplish this by simply reregistering the command to a command that simply prints an error message to the player:

 

dispatcher.register(Commands.literal(alias)
  .executes(commandContext -> {
    Minecraft.getInstance().player.sendSystemMessage(Component.literal("Alias " + alias " has been removed."));
    return Command.SINGLE_SUCCESS;
  })
);