protected void addSecuredSlot(IInventory other, int slot, int x, int y) {
if (other.getStackInSlot(slot) != null && inventory.itemClass.isAssignableFrom(other.getStackInSlot(slot).getItem().getClass()))
addSlot(new SlotLocked(other, slot, x, y));
else
addSlot(new SlotItemInventory(this, other, player, slot, x, y));
}