Error on open inventory, nothing shows up

I tried to do this, but nothing happening.

Code:

Inventory i = plugin.getServer().createInventory(player, InventoryType.MERCHANT);
player.openInventory(i);

What I did wrong?

 

createInventory asks for an inventory holder.
This refers to the owner of the inventory that will be created.

Too bad players are not merchants. You need to pass a mob that is a merchant.
One of those NPCs. I think that's easier said than done.

 

This may help you, I'm not sure though.

From the javadocs:

owner - The holder of the inventory; can be null if there's no holder.

 

So I can't create a Merchant GUI with command? Only with Villager?

 

Maybe, maybe not: try setting the inventory holder to null or a Villager object you have defined previously.