InventoryView.java

    /**
     * Get the inventory in this view that contains the given slot.
     * @param rawSlot a raw slot number
     * @return the inventory with that slot number, or null if not applicable
     */
    public final Inventory getInventoryWithSlot(int rawSlot) {
        int numInTop = getTopInventory().getSize();
        if (rawSlot < 0) {
            return null;
        } else if (rawSlot < numInTop) {
            return getTopInventory();
        } else if (rawSlot < numInTop + getBottomInventory().getSize()) {
            return getBottomInventory();
        }
        return null;
    }