code: public static boolean validateSignatureForPost(String body, Map<String, String> headers, String url, String apiKey) throws OneTouchException, UnsupportedEncodingException {
          HashMap<String, String> params = new HashMap<>();
          if (body == null || body.isEmpty())
              throw new OneTouchException("'PARAMS' are missing.");
          extract("", new JSONObject(body), params);
          return validateSignature(params, headers, "POST", url, apiKey);
      }
docs: Validates the request information to
  
  @param body    The body of the request in case of a POST method
  @param headers The headers of the request
  @param url     The url of the request.
  @param apiKey  the security token from the authy library
  @return true if the signature ios valid, false otherwise
  @throws com.authy.OneTouchException
  @throws UnsupportedEncodingException if the string parameters have problems with UTF-8 encoding.