public @DialogMessage @Nullable String validate() {
    if (!checkNumericFieldValue(myProxyGroup.getPort())) {
      return message("dialog.edit.http.proxies.settings.port.must.be.number.error", myProxyGroup.getName());
    }

    if (!checkNumericFieldValue(myProxyGroup.getTimeout())) {
      return message("dialog.edit.http.proxies.settings.timeout.must.be.number.error", myProxyGroup.getName());
    }

    return null;
  }
public @DialogMessage @Nullable String validate()