Utilis sample

bytes2hexStr.java

private static String toHexString(byte[] bytes) {
    StringBuilder sb = new StringBuilder(bytes.length * 2);
    for (int i = 0; i < bytes.length; i++) {
        String hex = Integer.toHexString(bytes[i] & 0xff);
        if (hex.length() == 1) {
            sb.append("0");
        }
        sb.append(hex);
    }

    return sb.toString();
}