我使用 AbstractPdfView 類生成 pdf 并在瀏覽器中下載，但我還需要通過電子郵件發送它。我知道解決方案非常明顯，但我已經堅持了一天，看不到它。這是我到目前為止所擁有的：@GetMapping()public PdfView generate(Model model, @RequestParam int event) {  model.addAttribute("event", eventService.getEventById(event));  return new PdfView();}那是 PdfView 類：public class PdfView extends AbstractPdfView {   @Override   protected void buildPdfDocument(Map<String, Object> model, Document document, PdfWriter writer, HttpServletRequest request, HttpServletResponse response) throws Exception {        //add the iformation for the pdf        document.add(getInvoiceInfo());   }}這就是 AbstractPdfView 類：public abstract class AbstractPdfView extends AbstractView {   public AbstractPdfView() {      setContentType("application/pdf");   }   @Override   protected boolean generatesDownloadContent() {      return true;   }   @Override   protected final void renderMergedOutputModel(Map<String, Object> model, HttpServletRequest request, HttpServletResponse response) throws Exception {  ByteArrayOutputStream out = createTemporaryOutputStream();  Document document = new Document(PageSize.A4.rotate(), 35, 35, 50, 36);  PdfWriter writer = PdfWriter.getInstance(document, out);  prepareWriter(model, writer, request);  buildPdfMetadata(model, document, request);  document.open();  buildPdfDocument(model, document, writer, request, response);  document.close();    //i know i has to happen before this bit here but not sure how   writeToResponse(response, out);}   protected void prepareWriter(Map<String, Object> model, PdfWriter writer, HttpServletRequest request) throws DocumentException {      writer.setViewerPreferences(getViewerPreferences());   }   protected int getViewerPreferences() {      return PdfWriter.ALLOW_PRINTING | PdfWriter.PageLayoutSinglePage;   }   protected void buildPdfMetadata(Map<String, Object> model, Document document, HttpServletRequest request) {   }歡迎任何幫助！感謝你們。