Expanding profession abilities

---

Once you have made your own profession, it's time to move on! You'd probably want it to be modifiable with commands. If you've worked with Mojang's Brigadier before, this shouldn't be a problem.

Let's assume that we have created trader profession. We want to modify the payment item of our profession.

TraderCommand.java

public class TraderCommand {

    public static void register(CommandDispatcher<CommandSourceStack> dispatcher, boolean dedicated) {
        dispatcher.register(literal("trader")
            .then(literal("changeCurrency")
                .then(argument("currency item", ItemStackArgumentType.itemStack())
                    .executes(TraderCommand::changeCurrency)
                )   
            )
        );
    }

    private static int changeCurrency(CommandContext<CommandSourceStack> context) throws CommandSyntaxException {
        // Getting the selected Taterzen
        ServerPlayer player = context.getSource().getPlayer();
        TaterzenNPC npc = ((TaterzenEditor) player).getNpc();
        if(npc != null) {
            // Getting the profession if NPC has it
            TraderProfession profession = npc.getProfession(TraderProfession.ID);
            if(profession != null) {
                ItemStack stack = ItemStackArgumentType.getItemStackArgument(commandContext, "currency item");
                profession.editCurrency(stack);
                return 1;
            }
            // Otherwise send error
            player.sendMessage(new TextComponent("This npc doesn't have trader profession :'( ..."), false);
        } else
            player.sendMessage(noSelectedTaterzenError(), false);
        return 0;
    }
}

Make sure to register your command as well.