asciichannel.java

POS is a Java&#174 platform-based, mission-critical, ISO-8583 based financial transaction library/fr

/*
 * jPOS Project [http://jpos.org]
 * Copyright (C) 2000-2008 Alejandro P. Revilla
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

package org.jpos.iso.channel;

import java.io.IOException;
import java.net.ServerSocket;

import org.jpos.iso.BaseChannel;
import org.jpos.iso.ISOChannel;
import org.jpos.iso.ISOException;
import org.jpos.iso.ISOMsg;
import org.jpos.iso.ISOPackager;
import org.jpos.iso.ISOUtil;

/**
 * ISOChannel implementation suitable for OASIS Ltd &copy; hosts<br>
 * (four ASCII characters header indicating message length)
 *
 * @author [e-mail]
 * @version $Id: ASCIIChannel.java 2594 2008-01-22 16:41:31Z apr $
 * @see ISOMsg
 * @see ISOException
 * @see ISOChannel
 */
public class ASCIIChannel extends BaseChannel {
    /**
     * Public constructor (used by Class.forName("...").newInstance())
     */
    public ASCIIChannel () {
        super();
    }
    /**
     * Construct client ISOChannel
     * @param host  server TCP Address
     * @param port  server port number
     * @param p     an ISOPackager
     * @see ISOPackager
     */
    public ASCIIChannel (String host, int port, ISOPackager p) {
        super(host, port, p);
    }
    /**
     * Construct server ISOChannel
     * @param p     an ISOPackager
     * @exception IOException
     * @see ISOPackager
     */
    public ASCIIChannel (ISOPackager p) throws IOException {
        super(p);
    }
    /**
     * constructs a server ISOChannel associated with a Server Socket
     * @param p     an ISOPackager
     * @param serverSocket where to accept a connection
     * @exception IOException
     * @see ISOPackager
     */
    public ASCIIChannel (ISOPackager p, ServerSocket serverSocket) 
        throws IOException
    {
        super(p, serverSocket);
    }
    /**
     * @param len the packed Message len
     * @exception IOException
     */
    protected void sendMessageLength(int len) throws IOException {
        if (len > 9999)
            throw new IOException ("len exceeded");

        try {
            serverOut.write(
                ISOUtil.zeropad(Integer.toString(len), 4).getBytes()
            );
        } catch (ISOException e) { }
    }
    /**
     * @return the Message len
     * @exception IOException, ISOException
     */
    protected int getMessageLength() throws IOException, ISOException {
        int l = 0;
        byte[] b = new byte[4];
        while (l == 0) {
            serverIn.readFully(b,0,4);
            try {
                if ((l=Integer.parseInt(new String(b))) == 0) {
                    serverOut.write(b);
                    serverOut.flush();
                }
            } catch (NumberFormatException e) { 
                throw new ISOException ("Invalid message length "+new String(b));
            }
        }
        return l;
    }
}