code: private void handleBody(Request.Builder builder) {
  		HttpMethod method = getMethod();
  		RequestBody body = hasBody() ? createBody() : null;
  
  		// Force an empty body, as POST & PUT methods requires
  		// a body element.
  		if (body == null && method.isBodyAllowed()) {
  			body = createEmptyBody();
  		}
  
  		builder.method(method.getVerb(), body);
  	}
docs: Add request body if appropriate:
  <ul>
  <li>Add request body if {@link #body} is defined.</li>
  <li>Add form parameters ({@link #formParams} otherwise if it is not empty.</li>
  </ul>
  
  @param builder The native OkHttp request builder.
  @see Request.Builder#method(String, RequestBody)
  @see RequestBody