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.iso;
020
021import java.io.IOException;
022import java.io.InputStream;
023
024/**
025 * Core interface for ISO-8583 packagers; responsible for packing and unpacking {@link org.jpos.iso.ISOMsg} instances.
026 * @author apr
027 * @version $Id$
028 * @see ISOComponent
029 */
030public interface ISOPackager {
031    /**
032     * Packs an ISO-8583 message into a byte array.
033     * @param   m   the Component to pack
034     * @return      Message image
035     * @exception ISOException on packing error
036     */
037    byte[] pack(ISOComponent m) throws ISOException;
038
039    /**
040     * Unpacks an ISO-8583 byte array into the given message container.
041     * @param   m   the Container of this message
042     * @param   b   ISO message image
043     * @return      consumed bytes
044     * @exception ISOException on unpacking error
045     */
046    int unpack(ISOComponent m, byte[] b) throws ISOException;
047
048    /**
049     * Unpacks an ISO-8583 message from an input stream into the given container.
050     * @param m the container
051     * @param in the input stream
052     * @throws IOException on I/O failure
053     * @throws ISOException on unpacking error
054     */
055    void unpack(ISOComponent m, InputStream in) throws IOException, ISOException;
056
057    /**
058     * Returns a human-readable description of this packager.
059     * @return  Packager's Description
060     */
061    String getDescription();
062    
063    /**
064     * Emits a description of the field identified by {@code fldno} in the given message to the log event.
065     * @param   m   the Container (i.e. an ISOMsg)
066     * @param   fldNumber the Field Number
067     * @return  Field Description
068     */
069    String getFieldDescription(ISOComponent m, int fldNumber);
070
071    /**
072     * Creates and returns a new ISOMsg instance appropriate for this packager.
073     * @return a new ISOMsg
074     */
075    ISOMsg createISOMsg();
076}
077