class aws_request {

public static String bytesToHex(byte[] hash) {
    ...
    return hexString.toString();
}

private static byte[] HmacSHA256(String data, byte[] key) throws Exception {
    ...
    return mac.doFinal(data.getBytes("UTF8"));
}

private static byte[] getSignatureKey(String key, String dateStamp, String regionName, String serviceName)
        throws Exception {
    ...
    return kSigning;
}

public static String getAuthorization() {
    try {...
        return authorization;
    } catch (Exception e) {
        return "failed";
    }

}
public static void main(String args[]) {
    vars.put("aaauthorization", getAuthorization());
}
}