具体实现代码

public void generatingPdf(HttpServletResponse response, GetAllAgencyMedalRankVo vo, List<ExamStandardPlayerVo> playerVos) {
        // 先将要合并的已有PDF文件列表准备好
        String fileName = "pdfModule/training.pdf";
        ClassPathResource resource = new ClassPathResource(fileName);
        String path = resource.getPath();
        String fileName2 = "pdfModule/introduction.pdf";
        ClassPathResource resource2 = new ClassPathResource(fileName2);
        String path2 = resource2.getPath();
        List<String> existingPdfFiles = Arrays.asList(path2,path);

        try {
            response.setContentType("application/pdf");

            // 创建合并文档
            Document mergedDocument = new Document();
            PdfCopy copy = new PdfCopy(mergedDocument, response.getOutputStream());
            mergedDocument.open();

            // 1. 先生成动态内容到内存
            byte[] dynamicContent = generateDynamicContent(vo, playerVos);
            PdfReader dynamicReader = new PdfReader(dynamicContent);

            // 添加动态生成的内容
            for (int i = 1; i <= dynamicReader.getNumberOfPages(); i++) {
                copy.addPage(copy.getImportedPage(dynamicReader, i));
            }
            copy.freeReader(dynamicReader);
            dynamicReader.close();

            // 2. 添加已有的PDF文件
            for (String existingFile : existingPdfFiles) {
                PdfReader existingReader = new PdfReader(existingFile);
                for (int i = 1; i <= existingReader.getNumberOfPages(); i++) {
                    copy.addPage(copy.getImportedPage(existingReader, i));
                }
                copy.freeReader(existingReader);
                existingReader.close();
            }

            mergedDocument.close();

        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * 生成动态内容到字节数组
     */
    private byte[] generateDynamicContent(GetAllAgencyMedalRankVo vo, List<ExamStandardPlayerVo> playerVos) {
        Document document = new Document();
        ByteArrayOutputStream baos = new ByteArrayOutputStream();

        try {
            PdfWriter writer = PdfWriter.getInstance(document, baos);
            document.setPageSize(PageSize.A4);

            // 设置页眉
            PdfPTable pdfPTable = buildHead(vo);
            pdfPTable.setWidthPercentage(50);
            ExamTablePdf.Header headerTable = new ExamTablePdf.Header(pdfPTable);
            headerTable.setTableHeader(writer, pdfPTable);

            document.open();

            // 你原有的内容生成代码
            PdfPTable title = getTable(null, 560, new PdfPTable(1));
            PdfPCell cellTile = getTableCell(new Paragraph("", miniHeadfont), 15, Element.ALIGN_CENTER, false);
            title.addCell(cellTile);
            document.add(title);
            document.add(new Paragraph("\n"));

            PdfPTable titleTable = getTable(null, 560, new PdfPTable(3));
            PdfPCell cell = getTableCell(new Paragraph("体能测评", smallHeadfont), 13, Element.ALIGN_LEFT, false);
            titleTable.addCell(cell);
            cell = getTableCell(new Paragraph("", smallHeadfont), 13, Element.ALIGN_CENTER, false);
            titleTable.addCell(cell);
            cell = getTableCell(new Paragraph("", smallHeadfont), 13, Element.ALIGN_RIGHT, false);
            titleTable.addCell(cell);
            document.add(titleTable);
            document.add(new Paragraph("\n"));

            // 构建内容表头
            PdfPTable contentTable = buildRankDetailTable();
            writeCombatDetailTableContext(contentTable, playerVos, false, document);
            document.add(contentTable);

            document.close();

        } catch (Exception e) {
            e.printStackTrace();
            if (document.isOpen()) {
                document.close();
            }
        }

        return baos.toByteArray();
    }