[2 Problems] Java exeption thrown | os.loadAPI not working

os.loadAPI("items")

local me = peripheral.find("tileinterface")
local m = peripheral.find("monitor")
local sSide = "right"

local function centerText(text, y)
	mX = m.getSize()
	x = math.floor(mX/2) - math.floor(string.len(text)/2)
	m.setCursorPos(x,y)
	m.write(text)
end

local function setupMonitor()
	m.clear()
	m.setTextColor(colors.white)
	m.setBackgroundColor(colors.black)
	centerText("Global Mob-Spawn System",1)
	m.setCursorPos(1,3)
	m.write("Mob:")
	m.setCursorPos(16,3)
	m.write("State:")
	m.setCursorPos(34,3)
	m.write("Color:")
	m.setCursorPos(1,4)
	m.write("--------------------------------------------------")
end

local function setOnline()
	rs.setBundledOutput(sSide, colors.combine(rs.getBundledOutput(sSide), curcolor))
	m.setCursorPos(16,curline)
	m.setBackgroundColor(colors.green)
	m.write(" ONLINE ")
	m.setBackgroundColor(colors.gray)
	m.write(" OFFLINE ")
end

local function setOffline()
	rs.setBundledOutput(sSide, colors.subtract(rs.getBundledOutput(sSide), curcolor))
	m.setCursorPos(16,curline)
	m.setBackgroundColor(colors.gray)
	m.write(" ONLINE ")
	m.setBackgroundColor(colors.red)
	m.write(" OFFLINE ")
end

local function updateList()
	local list = me.getAvailableItems()
	for num, item in pairs(list) do
		for n, i in pairs(mobdrops) do
			curline = i.line
			curcolor = i.color
			if i.mob == "Pech" then
				if item.fingerprint.nbt_hash == i.nbt then
					if item.size < i.qty then
						if i.nbt == "ad5cc1bd74d2230c5c483e4c1bbc7948" then ignis = "1"
						elseif i.nbt == "bb9211b894dea99a6b674ebe63759333" then terra = "1"
						elseif i.nbt == "64630f917da3a7214b1ef2c91a90d090" then aer = "1"
						elseif i.nbt == "358c318e194980b0c0835a9f1ce41750" then aqua  = "1"
						elseif i.nbt == "a77c4b35bbb1a4c84b15122dd52354bf" then ordo = "1"
						elseif i.nbt == "18add493aeeb97a3fe71cf8130fe8675" then perditio = "1" end
					elseif item.size >= i.qty then
						if i.nbt == "ad5cc1bd74d2230c5c483e4c1bbc7948" then ignis = "2"
						elseif i.nbt == "bb9211b894dea99a6b674ebe63759333" then terra = "2"
						elseif i.nbt == "64630f917da3a7214b1ef2c91a90d090" then aer = "2"
						elseif i.nbt == "358c318e194980b0c0835a9f1ce41750" then aqua  = "2"
						elseif i.nbt == "a77c4b35bbb1a4c84b15122dd52354bf" then ordo = "2"
						elseif i.nbt == "18add493aeeb97a3fe71cf8130fe8675" then perditio = "2" end
					end
				end
				if ignis == "2" and terra == "2" and aer == "2" and aqua == "2" and ordo == "2" and perditio == "2" then
					setOffline()
				else
					setOnline()
				end
			else
				if item.fingerprint.id == i.id and item.fingerprint.dmg == i.dmg and item.size < i.qty then
					setOnline()
				elseif item.fingerprint.id == i.id and item.fingerprint.dmg == i.dmg and item.size >= i.qty then
					setOffline()
				end
			end
			m.setBackgroundColor(colors.black)
			m.setCursorPos(1,i.line)
			m.write(i.mob)
			m.setCursorPos(36,i.line)
			m.setBackgroundColor(i.color)
			m.write("  ")
			m.setBackgroundColor(colors.black)
		end
	end
	sleep(1)
end

local function startScan()
	rs.setBundledOutput(sSide, 0)
	while true do
		updateList()
		sleep (1)
	end
end

setupMonitor()
startScan()

ignis = "2"
terra = "2"
aer = "2"
aqua = "2"
ordo = "2"
perditio = "2"

mobdrops = {
	leather = {
		mob = "Horse",
		color = colors.red,
		id = "minecraft:leather",
		nbt = "",
		dmg = 0,
		qty = 64,
		line = 5
	},
	
	feather = {
		mob = "Chicken",
		color = colors.green,
		id = "minecraft:feather",
		nbt = "",
		dmg = 0,
		qty = 64,
		line = 6
	},
	
	blazerod = {
		mob = "Blaze",
		color = colors.brown,
		id = "minecraft:blaze_rod",
		nbt = "",
		dmg = 0,
		qty = 128,
		line = 7
	},
	
	witherskull = {
		mob = "WhiterSkeleton",
		color = colors.blue,
		id = "minecraft:skull",
		nbt = "",
		dmg = 1,
		qty = 30,
		line = 8
	},
	
	inksack = {
		mob = "Squid",
		color = colors.purple,
		id = "minecraft:dye",
		nbt = "",
		dmg = 0,
		qty = 128,
		line = 9
	},
	
	wool = {
		mob = "Sheep",
		color = colors.cyan,
		id = "minecraft:wool",
		nbt = "",
		dmg = 0,
		qty = 128,
		line = 10
	},
	
	bones = {
		mob = "Skeleton",
		color = colors.lightGray,
		id = "minecraft:bone",
		nbt = "",
		dmg = 0,
		qty = 128,
		line = 11
	},
	
	gunpowder = {
		mob = "Creeper",
		color = colors.gray,
		id = "minecraft:gunpowder",
		nbt = "",
		dmg = 0,
		qty = 256,
		line = 12
	},
	
	slimeball = {
		mob = "Slime",
		color = colors.pink,
		id = "minecraft:slime_ball",
		nbt = "",
		dmg = 0,
		qty = 128,
		line = 13
	},
	
	ghasttear = {
		mob = "Ghast",
		color = colors.lime,
		id = "minecraft:ghast_tear",
		nbt = "",
		dmg = 0,
		qty = 64,
		line = 14
	},
	
	pinkslimeball = {
		mob = "Pink Slime",
		color = colors.yellow,
		id = "MineFactoryReloaded:pinkslime",
		nbt = "",
		dmg = 0,
		qty = 72,
		line = 15
	},
	
	mana_ignis = {
		name = ignis,
		mob = "Pech",
		color = colors.lightBlue,
		id = "Thaumcraft:ItemManaBean",
		nbt = "ad5cc1bd74d2230c5c483e4c1bbc7948",
		dmg = 0,
		qty = 256,
		line = 16
	},
	
	mana_terra = {
		name = terra,
		mob = "Pech",
		color = colors.lightBlue,
		id = "Thaumcraft:ItemManaBean",
		nbt = "bb9211b894dea99a6b674ebe63759333",
		dmg = 0,
		qty = 256,
		line = 16
	},
	
	mana_aer = {
		name = aer,
		mob = "Pech",
		color = colors.lightBlue,
		id = "Thaumcraft:ItemManaBean",
		nbt = "64630f917da3a7214b1ef2c91a90d090",
		dmg = 0,
		qty = 256,
		line = 16
	},
	
	mana_aqua = {
		name = aqua,
		mob = "Pech",
		color = colors.lightBlue,
		id = "Thaumcraft:ItemManaBean",
		nbt = "358c318e194980b0c0835a9f1ce41750",
		dmg = 0,
		qty = 256,
		line = 16
	},
	
	mana_ordo = {
		name = ordo,
		mob = "Pech",
		color = colors.lightBlue,
		id = "Thaumcraft:ItemManaBean",
		nbt = "a77c4b35bbb1a4c84b15122dd52354bf",
		dmg = 0,
		qty = 256,
		line = 16
	},
	
	mana_perditio = {
		name = perditio,
		mob = "Pech",
		color = colors.lightBlue,
		id = "Thaumcraft:ItemManaBean",
		nbt = "18add493aeeb97a3fe71cf8130fe8675",
		dmg = 0,
		qty = 256,
		line = 16
	}
}