public ArrayList<String> getAllCategorys() {
		ArrayList<String> categorys = new ArrayList<String>();
		try {
			Connection conn = openConnection();
			Statement stat = conn.createStatement();
			ResultSet rs = stat.executeQuery("select name from "
					+ DB_CATEGORY_TABLE + ";");
			while (rs.next()) {
				categorys.add(rs.getString("name"));
			}
			rs.close();
			conn.close();
		} catch (Exception e) {
			e.printStackTrace();
		}
		return categorys;
	}