code: protected String getRequestBody(HttpServerExchange exchange) throws IOException {
          String body = "";
          if (RequestUtils.isPostPutPatch(exchange)) {
              exchange.startBlocking();
              body = IOUtils.toString(exchange.getInputStream(), Default.ENCODING.toString());
          }
  
          return body;
      }
docs: Retrieves the complete request body from the request
  
  @param exchange The Undertow HttpServerExchange
  @return A body object containing the request body
  
  @throws IOException