/* * Copyright (c) 2000 jPOS.org. All rights reserved. *  * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: *  1. Redistributions of source code must retain the above copyright notice, * this list of conditions and the following disclaimer. *  2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. *  3. The end-user documentation included with the redistribution, if any, * must include the following acknowledgment: "This product includes software * developed by the jPOS project (http://www.jpos.org/)". Alternately, this * acknowledgment may appear in the software itself, if and wherever such * third-party acknowledgments normally appear. *  4. The names "jPOS" and "jPOS.org" must not be used to endorse or promote * products derived from this software without prior written permission. For * written permission, please contact license@jpos.org. *  5. Products derived from this software may not be called "jPOS", nor may * "jPOS" appear in their name, without prior written permission of the jPOS * project. *  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE JPOS * PROJECT OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * ==================================================================== *  * This software consists of voluntary contributions made by many individuals * on behalf of the jPOS Project. For more information please see * <http://www.jpos.org/> . */package org.jpos.iso;/** * AsciiPrefixer constructs a prefix for ASCII messages. *  * @author joconnor * @version $Revision: 1.5 $ $Date: 2004/07/02 13:18:22 $ */public class AsciiPrefixer implements Prefixer{    /**     * A length prefixer for upto 9 chars. The length is encoded with 1 ASCII     * char representing 1 decimal digit.     */    public static final AsciiPrefixer L = new AsciiPrefixer(1);    /**	 * A length prefixer for upto 99 chars. The length is encoded with 2 ASCII	 * chars representing 2 decimal digits.	 */    public static final AsciiPrefixer LL = new AsciiPrefixer(2);    /**	 * A length prefixer for upto 999 chars. The length is encoded with 3 ASCII	 * chars representing 3 decimal digits.	 */    public static final AsciiPrefixer LLL = new AsciiPrefixer(3);    /**	 * A length prefixer for upto 9999 chars. The length is encoded with 4	 * ASCII chars representing 4 decimal digits.	 */    public static final AsciiPrefixer LLLL = new AsciiPrefixer(4);    /**     * A length prefixer for upto 99999 chars. The length is encoded with 5     * ASCII chars representing 5 decimal digits.     */    public static final AsciiPrefixer LLLLL = new AsciiPrefixer(5);    /**     * A length prefixer for upto 999999 chars. The length is encoded with 6     * ASCII chars representing 6 decimal digits.     */    public static final AsciiPrefixer LLLLLL = new AsciiPrefixer(6);    //private static final LeftPadder PADDER = LeftPadder.ZERO_PADDER;    //private static final AsciiInterpreter INTERPRETER = AsciiInterpreter.INSTANCE;    /** The number of digits allowed to express the length */    private int nDigits;        public AsciiPrefixer(int nDigits)    {        this.nDigits = nDigits;    }    /*	 * (non-Javadoc)	 * 	 * @see org.jpos.iso.Prefixer#encodeLength(int, byte[])	 */    public void encodeLength(int length, byte[] b) throws ISOException    {        int n = length;        // Write the string backwards - I don't know why I didn't see this at first.        for (int i = nDigits - 1; i >= 0; i--)        {            b[i] = (byte)(n % 10 + '0');            n /= 10;        }        if (n != 0)        {            throw new ISOException("invalid len "+ length + ". Prefixing digits = " + nDigits);        }    }    /*	 * (non-Javadoc)	 * 	 * @see org.jpos.iso.Prefixer#decodeLength(byte[], int)	 */    public int decodeLength(byte[] b, int offset)    {        int len = 0;        for (int i = 0; i < nDigits; i++)        {            len = len * 10 + b[offset + i] - (byte)'0';        }        return len;    }    /*	 * (non-Javadoc)	 * 	 * @see xcom.traxbahn.iso.Prefixer#getLengthInBytes()	 */    public int getPackedLength()    {        return nDigits;    }}