private static String convertToHex(byte[] data) {
		StringBuffer buffer = new StringBuffer();
		for (int i = 0; i < data.length; i++) {
			int halfbyte = (data[i] >>> 4) & 0x0F;
			int two_halfs = 0;
			do {
				if ((0 <= halfbyte) && (halfbyte <= 9)) {
					buffer.append((char) ('0' + halfbyte));
				} else {
					buffer.append((char) ('a' + (halfbyte - 10)));
				}
				halfbyte = data[i] & 0x0F;
			} while (two_halfs++ < 1);
		}
		return buffer.toString();
	}