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This artifact provides a single jar that contains all classes required to use remote Jakarta Enterprise Beans and Jakarta Messaging, including all dependencies. It is intended for use by those not using maven, maven users should just import the Jakarta Enterprise Beans and Jakarta Messaging BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

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/*
 * JBoss, Home of Professional Open Source.
 * Copyright 2011, Red Hat, Inc., and individual contributors
 * as indicated by the @author tags. See the copyright.txt file in the
 * distribution for a full listing of individual contributors.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This software 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */

package org.jboss.sasl.util;

/**
 * A utility class for mapping between byte arrays and their hex representation and back again.
 *
 * @author Darran Lofthouse
 */
public class HexConverter {

    private static final char[] HEX_CHARS = new char[]
            {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};

    private static final byte[] HEX_BYTES = new byte[]
            {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};

    /**
     * Take the supplied byte array and convert it to a hex encoded String.
     *
     * @param toBeConverted - the bytes to be converted.
     * @return the hex encoded String.
     */
    public static String convertToHexString(byte[] toBeConverted) {
        if (toBeConverted == null) {
            throw new NullPointerException("Parameter to be converted can not be null");
        }

        char[] converted = new char[toBeConverted.length * 2];
        for (int i = 0; i < toBeConverted.length; i++) {
            byte b = toBeConverted[i];
            converted[i * 2] = HEX_CHARS[b >> 4 & 0x0F];
            converted[i * 2 + 1] = HEX_CHARS[b & 0x0F];
        }

        return String.valueOf(converted);
    }

    /**
     * Take the supplied byte array and convert it to to a byte array of the encoded
     * hex values.
     * 
     * Each byte on the incoming array will be converted to two bytes on the return
     * array.
     *
     * @param toBeConverted - the bytes to be encoded.
     * @return the encoded byte array.
     */
    public static byte[] convertToHexBytes(byte[] toBeConverted) {
        if (toBeConverted == null) {
            throw new NullPointerException("Parameter to be converted can not be null");
        }

        byte[] converted = new byte[toBeConverted.length * 2];
        for (int i = 0; i < toBeConverted.length; i++) {
            byte b = toBeConverted[i];
            converted[i * 2] = HEX_BYTES[b >> 4 & 0x0F];
            converted[i * 2 + 1] = HEX_BYTES[b & 0x0F];
        }

        return converted;
    }

    /**
     * Take the incoming character of hex encoded data and convert to the raw byte values.
     * 

     * The characters in the incoming array are processed in pairs with two chars of a pair
     * being converted to a single byte.
     *
     * @param toConvert - the hex encoded String to convert.
     * @return the raw byte array.
     */
    public static byte[] convertFromHex(final char[] toConvert) {
        if (toConvert.length % 2 != 0) {
            throw new IllegalArgumentException("The supplied character array must contain an even number of hex chars.");
        }

        byte[] response = new byte[toConvert.length / 2];

        for (int i = 0; i < response.length; i++) {
            int posOne = i * 2;
            response[i] =   (byte)(toByte(toConvert, posOne) << 4 | toByte(toConvert, posOne+1));
        }

        return response;
    }

    private static byte toByte(final char[] toConvert, final int pos) {
        int response = Character.digit(toConvert[pos], 16);
        if (response < 0 || response > 15) {
            throw new IllegalArgumentException("Non-hex character '" + toConvert[pos] + "' at index=" + pos);
        }

        return (byte) response;
    }

    /**
     * Take the incoming String of hex encoded data and convert to the raw byte values.
     * 
     * The characters in the incoming String are processed in pairs with two chars of a pair
     * being converted to a single byte.
     *
     * @param toConvert - the hex encoded String to convert.
     * @return the raw byte array.
     */
    public static byte[] convertFromHex(final String toConvert) {
        return convertFromHex(toConvert.toCharArray());
    }

    public static void main(String[] args) {
        byte[] toConvert = new byte[256];
        for (int i = 0; i < toConvert.length; i++) {
            toConvert[i] = (byte) i;
        }

        String hexValue = convertToHexString(toConvert);

        System.out.println("Converted - " + hexValue);

        byte[] convertedBack = convertFromHex(hexValue);

        StringBuffer sb = new StringBuffer();
        for (byte current : convertedBack) {
            sb.append((int)current).append(" ");
        }
        System.out.println("Converted Back " + sb.toString());
    }

}