Create a simple inv

Create a simple inventar

-- Create inventory
local title = "This is the inventory title"
local slots = 9
local inv = plugin.getServer():createInventory(nil, slots, title)
-- Open inventory for player
player:openInventory(inv)

Make sure thah your slots number can be divided by 9 and is lower then 55 (max. Slots 54)

inv_simple

Set an item for the inventory

-- Import utils
local itemStack = import("org.bukkit.inventory.ItemStack")
local material = import("$.Material")
-- Create inventory
local title = "This is the inventory title"
local slots = 9
local inv = plugin.getServer():createInventory(nil, slots, title)

-- Create new item stack
local countOfItems = 1
local newItemStack = luajava.new(itemStack, material.GRASS, countOfItems, 0)
-- Set item to a slot
local setSlot = 0
inv:setItem(setSlot, newItemStack)
-- Open inventory for player
player:openInventory(inv)

This code allows you to open an inventory with an grass block item in the first slot of the inventory

inv_with_item