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
022/**
023 *
024 * Multipurpose sequencer.<br>
025 * CardAgents requires persistent sequence number<br>
026 * Sequencer interface isolate from particular DB implementations
027 *
028 * @author apr@cs.com.uy
029 * @version $Id$
030 * @since jPOS 1.1
031 *
032 */
033public interface Sequencer {
034    /**
035     * Increments {@code counterName} by 1 and returns its new value.
036     *
037     * @param counterName name of the counter
038     * @return the counter's new value
039     */
040    int get(String counterName);
041    /**
042     * Increments {@code counterName} by {@code add} and returns its new value.
043     *
044     * @param counterName name of the counter
045     * @param add increment to apply
046     * @return the counter's new value
047     */
048    int get(String counterName, int add);
049    /**
050     * Replaces the value of {@code counterName}.
051     *
052     * @param counterName name of the counter
053     * @param value new value
054     * @return the previous value
055     */
056    int set(String counterName, int value);
057}