001/*
002 * jPOS Project [http://jpos.org]
003 * Copyright (C) 2000-2026 jPOS Software SRL
004 *
005 * This program is free software: you can redistribute it and/or modify
006 * it under the terms of the GNU Affero General Public License as
007 * published by the Free Software Foundation, either version 3 of the
008 * License, or (at your option) any later version.
009 *
010 * This program is distributed in the hope that it will be useful,
011 * but WITHOUT ANY WARRANTY; without even the implied warranty of
012 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
013 * GNU Affero General Public License for more details.
014 *
015 * You should have received a copy of the GNU Affero General Public License
016 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
017 */
018
019package org.jpos.core;
020
021/** Strategy interface for LUHN check-digit calculation and verification. */
022public interface LUHNCalculator {
023    /**
024     * Verifies the LUHN check digit of a full PAN.
025     * @param pan the full card PAN including check digit
026     * @return {@code true} if the check digit is valid
027     * @throws InvalidCardException if the PAN is null or too short
028     */
029    boolean verify (String pan) throws InvalidCardException;
030    /**
031     * Computes the LUHN check digit for a PAN body (without check digit).
032     * @param pan the PAN without the check digit
033     * @return the computed check digit character
034     * @throws InvalidCardException if the PAN contains non-digit characters
035     */
036    char calculate (String pan) throws InvalidCardException;
037}