/*******************************************************************************
* Software Name : RCS IMS Stack
*
* Copyright (C) 2010 France Telecom S.A.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
******************************************************************************/
package com.orangelabs.rcs.utils;
/**
* Hexadecimal utils
*
* @author Deutsche Telekom AG
*/
public class HexadecimalUtils {
/**
* Decode hex string to a byte array
*
* @param s hexadecimal encoded string
* @return array of bytes
*/
public static byte[] hexStringToByteArray(String s) {
if (s == null || s.length() == 0) {
return null;
}
int len = s.length();
// '111' is not a valid hex encoding.
if (len % 2 != 0) {
throw new IllegalArgumentException();
}
byte[] data = new byte[len / 2];
for (int i = 0; i < len; i += 2) {
data[i / 2] = (byte) ((Character.digit(s.charAt(i), 16) << 4)
+ Character.digit(s.charAt(i + 1), 16));
}
return data;
}
/**
* Convert byte array into Hexadecimal string
*
* @param bytes
* @return {@link String} if valid byte array, otherwise <code>null</code>
*/
public static String byteArrayToHexString(byte[] bytes) {
if (bytes == null || bytes.length == 0) {
return null;
}
final char[] hexArray = {'0','1','2','3','4','5','6','7','8','9','a','b','c','d','e','f'};
char[] hexChars = new char[bytes.length * 2];
int value;
for ( int j = 0; j < bytes.length; j++) {
value = bytes[j] & 0xFF;
hexChars[j * 2] = hexArray[value >>> 4];
hexChars[j * 2 + 1] = hexArray[value & 0x0F];
}
return new String(hexChars);
}
}