code: public String buildAuthorizationHeaderValue(HttpRequest request, byte[] body, OAuth1Credentials oauth1Credentials) {
  		Map<String, String> oauthParameters = commonOAuthParameters(oauth1Credentials.getConsumerKey());
  		oauthParameters.put("oauth_token", oauth1Credentials.getAccessToken());
  		MultiValueMap<String, String> additionalParameters = union(readFormParameters(request.getHeaders().getContentType(), body), parseFormParameters(request.getURI().getRawQuery()));
  		return buildAuthorizationHeaderValue(request.getMethod(), request.getURI(), oauthParameters, additionalParameters, oauth1Credentials.getConsumerSecret(), oauth1Credentials.getAccessTokenSecret());
  	}
docs: Builds an authorization header from a request.
  Expects that the request's query parameters are form-encoded.