1.引入依赖
<!--PDF导出POM-->
<dependency><groupId>com.itextpdf</groupId><artifactId>itext7-core</artifactId><version>8.0.3</version><type>pom</type>
</dependency>
<dependency><groupId>com.itextpdf</groupId><artifactId>html2pdf</artifactId><version>5.0.3</version>
</dependency>
<dependency><groupId>org.freemarker</groupId><artifactId>freemarker</artifactId><version>2.3.31</version>
</dependency>2.编写FTL文件
<!DOCTYPE html>
<html lang="en"><head><meta charset="UTF-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><title></title>
</head><style>.pic {width: 100%;height: 100%;}
</style><body>
<div id="app"><#--封面图--><#if show><img class="pic" src="${coverImageFile!''}"/></#if>
</div>
</body>
</html>3.后台代码
@Resource
Configuration configuration;/*** 导出*/@Overridepublic void export(HttpServletResponse response){//获取文件byte[]byte[] pdfBytes=getPdfBytes();try{//输出pdf文件String chineseName="中文文件名";response.setCharacterEncoding("utf-8");String fileName=URLEncoder.encode(chineseName, StandardCharsets.UTF_8).replaceAll("\\+", "%20");response.setHeader("Content-disposition", "attachment;filename*=" + fileName + ".pdf");//设置响应头（导出为pdf文件）response.setContentType("application/pdf");//设置响应头（返回流给前端预览使用）//response.setContentType("application/octet-stream;charset=UTF-8");// 获取HttpServletResponse的OutputStreamOutputStream os=response.getOutputStream();// 写入字节流数组os.write(pdfBytes);os.flush();os.close();}catch(IOException e){throw new InvalidCmdException(e.getMessage());}}private byte[] getPdfBytes(){//获取模板替换数据Map<String, Object> map=new HashMap<>();map.put("show", true);map.put("coverImageFile", "base64图片");try{//读取freemarker模板Template template=configuration.getTemplate("FTL文件路径");StringWriter out=new StringWriter();// 将数据模型合并到模板中生成HTMLtemplate.process(map, out);String htmlContent=out.toString();// 初始化字节输出流用于保存PDFByteArrayOutputStream pdfOutput=new ByteArrayOutputStream();// 设置中文字体ConverterProperties converterProperties=new ConverterProperties();FontProvider fontProvider=new DefaultFontProvider(true, true, false);PdfDocument pdfDoc;FontProgram fontProgram=FontProgramFactory.createFont("static/simhei.ttf");// 添加中文字体到字体提供者fontProvider.addFont(fontProgram);converterProperties.setFontProvider(fontProvider);// 转换HTML到PDFtry(ByteArrayOutputStream outputStream=pdfOutput){// 初始化文档PdfWriter writer=new PdfWriter(outputStream);pdfDoc=new PdfDocument(writer);//设置pdf纸张大小pdfDoc.setDefaultPageSize(PageSize.A4);// 将HTML转换为PDFHtmlConverter.convertToPdf(htmlContent, pdfDoc, converterProperties);}// 从字节输出流中获取PDF的字节数组byte[] pdfBytes=pdfOutput.toByteArray();// 关闭流pdfOutput.close();pdfDoc.close();out.close();return pdfBytes;}catch(IOException e){throw new InvalidCmdException("读取候选人freemarker模板错误");}catch(TemplateException e){throw new InvalidCmdException("替换模板值错误");}}4.注意事项
itext7本身不支持中文 所以需要在项目中引入字体文件。
freemarker图片需要使用base64格式图片
byte[] 数组转base64
/*** 图片转base64*/private String convertBase64(String ossFileId){if(String2Utils.isNotBlank(ossFileId)){//这里使用的是阿里的oss查询OssUrlDto ossUrlDto=ossFileService.findDfsById(ossFileId).orElse(null);try{byte[] adviserBytes=ossClientService.getContentByteByKey(ossUrlDto.getBucketName(), ossUrlDto.getPath());return "data:image/jpeg;base64," + Base64.getEncoder().encodeToString(adviserBytes);}catch(Exception e){throw new InvalidCmdException("图片转base64失败");}}return "";}给导出的PDF设置页面边距，网上搜索了很多中办法，只有一种成功了
再FTL页面中添加
<style>@page {size: A4;margin: 10mm;}
</style>
