get category by recursion

    public ArrayList<Category> getSubcategoriesRecursivley(Category cat, ArrayList<Category> alc)
    {
        Boolean added = false;
        WebShop ws = WebShop.getInstance();
        alc.add(cat);
        ArrayList<Category> toBeAdded = new ArrayList<Category>();

        for (Category category : ws.getCategories().values())
        {
            for (Category cFromList : alc)
            {
                if (category.getParent() != null && category.getParent().equals(cFromList) && !alc.contains(category) && !toBeAdded.contains(category))
                {
                    toBeAdded.add(category);
                    added = true;
                }
            }
        }

        alc.remove(cat);

        if (added)
        {
            alc.addAll(toBeAdded);
            return getSubcategoriesRecursivley(cat, alc);
        }
        else
            return alc;
    }

    public ArrayList<Category> getSubcategories()
    {
        ArrayList<Category> list = new ArrayList<Category>();
        list = getSubcategoriesRecursivley(this, list);

        return list;
    }