code: public Connection submit() {
          String action = hasAttr("action") ? absUrl("action") : baseUri();
          Validate.notEmpty(action, "Could not determine a form action URL for submit. Ensure you set a base URI when parsing.");
          Connection.Method method = attr("method").toUpperCase().equals("POST") ?
                  Connection.Method.POST : Connection.Method.GET;
  
          return Jsoup.connect(action)
                  .data(formData())
                  .method(method);
      }
docs: Prepare to submit this form. A Connection object is created with the request set up from the form values. You
  can then set up other options (like user-agent, timeout, cookies), then execute it.
  @return a connection prepared from the values of this form.
  @throws IllegalArgumentException if the form's absolute action URL cannot be determined. Make sure you pass the
  document's base URI when parsing.