@Override
	public ArrayList<String> getAllCategories() {
		ArrayList<String> categories = new ArrayList<String>();
		TypedQuery<Category> categoryQuery = emgr.createNamedQuery("Category.findAll", Category.class);
		
		List<Category> categoriesList = (List<Category>) categoryQuery
				.getResultList();
		for (int i = 0; i < categoriesList.size(); i++) {
			categories.add(categoriesList.get(i).getCategoryName());
		}
		
		return categories;
	}