code: public static Optional<ButtonType> alert(String title, String header, String content, AlertType alertType,
                                               Modality modality, Window window, StageStyle style) {
          return getAlert(title, header, content, alertType, modality, window, style).showAndWait();
      }
docs: 弹窗
  
  @param title 标题
  @param header 信息头
  @param content 内容
  @param alertType {@link AlertType}
  @param modality {@link Modality}
  @param window {@link Window}
  @param style {@link StageStyle}
  
  @return {@link ButtonType}