代码：

java">		// 设置响应头
        response.setCharacterEncoding("UTF-8");//设置响应的字符编码为UTF-8
        response.setContentType("application/octet-stream");//设置响应的内容类型为二进制流，通常用于文件下载。
        response.setHeader("Content-Disposition", "attachment; filename=test.zip");//设置响应头中的Content-Disposition字段，告诉浏览器将响应内容作为附件处理，并指定下载文件的名称为test.zip。
        //创建xml文件1
        Document document = DocumentHelper.createDocument();
        Element root = document.addElement("root");
        Element test = root.addElement("test");
        test.addAttribute("name","淫龙公子");
        test.addAttribute("age","38");
        test.addAttribute("jjMaxLength","6cm");
        Element test1 = root.addElement("test");
        test1.addAttribute("name","yi龙公子");
        test1.addAttribute("age","66");
        test1.addAttribute("jjMaxLength","7cm");
        Element test2 = root.addElement("test");
        test2.addAttribute("name","王有");
        test2.addAttribute("age","77");
        test2.addAttribute("jjMaxLength","1cm");
        //创建xml文件2
        Document document1 = DocumentHelper.createDocument();
        Element root1 = document1.addElement("root");
        Element test11 = root1.addElement("test");
        test11.addAttribute("name","淫龙公子");
        test11.addAttribute("age","38");
        test11.addAttribute("jjMaxLength","6cm");
        Element test12 = root1.addElement("test");
        test12.addAttribute("name","yi龙公子");
        test12.addAttribute("age","66");
        test12.addAttribute("jjMaxLength","7cm");
        Element test13 = root1.addElement("test");
        test13.addAttribute("name","王有");
        test13.addAttribute("age","77");
        test13.addAttribute("jjMaxLength","1cm");
        //创建xml文件3
        Document document2 = DocumentHelper.createDocument();
        Element root2 = document2.addElement("root");
        Element test21 = root2.addElement("test");
        test21.addAttribute("name","淫龙公子");
        test21.addAttribute("age","38");
        test21.addAttribute("jjMaxLength","6cm");
        Element test22 = root2.addElement("test");
        test22.addAttribute("name","yi龙公子");
        test22.addAttribute("age","66");
        test22.addAttribute("jjMaxLength","7cm");
        Element test23 = root2.addElement("test");
        test23.addAttribute("name","王有");
        test23.addAttribute("age","77");
        test23.addAttribute("jjMaxLength","1cm");
        // 将XML转成字符串，后面能用工具类将字符串转成流
        String asXML = document.asXML();
        String asXML1 = document1.asXML();
        String asXML2 = document2.asXML();
        ZipOutputStream out = null;
        try {
            out = new ZipOutputStream(response.getOutputStream());
            //writeToZip：将xml流写到zip输出流中
            writeToZip(out,asXML,"test1.xml");
            writeToZip(out,asXML1,"test2.xml");
            writeToZip(out,asXML2,"test3.xml");
            out.flush();
            out.close();
        } catch (Exception e) {
            e.printStackTrace();
        }finally {
            if (out != null){
                try {
                    out.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }

writeToZip方法：

java">private void writeToZip(ZipOutputStream out,String xmlContent,String fileName) throws IOException {
        int len =0;
        byte[] buffer = new byte[1024];
        InputStream is = IOUtils.toInputStream(xmlContent, "utf-8");

            out.putNextEntry(new ZipEntry(fileName));
            while ((len = is.read(buffer)) >0){
                out.write(buffer,0,len);
            }

        out.closeEntry();
        is.close();

    }

注意：前后端分离项目中如果前端有响应拦截器，我们需要再做处理，例如vue项目的下载方法：

javascript">// 通用下载方法
export function download(url, params, filename, config) {
  downloadLoadingInstance = Loading.service({ text: "正在下载数据，请稍候", spinner: "el-icon-loading", background: "rgba(0, 0, 0, 0.7)", })
  return service.post(url, params, {
    transformRequest: [(params) => { return tansParams(params) }],
    headers: { 'Content-Type': 'application/x-www-form-urlencoded' },
    responseType: 'blob',
    ...config
  }).then(async (data) => {
    const isBlob = blobValidate(data);
    if (isBlob) {
      const blob = new Blob([data])
      saveAs(blob, filename)
    } else {
      const resText = await data.text();
      const rspObj = JSON.parse(resText);
      const errMsg = errorCode[rspObj.code] || rspObj.msg || errorCode['default']
      Message.error(errMsg);
    }
    downloadLoadingInstance.close();
  }).catch((r) => {
    console.error(r)
    Message.error('下载文件出现错误，请联系管理员！')
    downloadLoadingInstance.close();
  })
}

附加（导出xml文件）：

java">//导出xml文件
        // 设置响应头
        response.setCharacterEncoding("UTF-8");
        response.setContentType("application/octet-stream");
        response.setHeader("Content-Disposition", "attachment; filename=test.xml");
        //创建xml文件
        Document document = DocumentHelper.createDocument();
        Element root = document.addElement("root");
        Element test = root.addElement("test");
        test.addAttribute("name","淫龙公子");
        test.addAttribute("age","38");
        test.addAttribute("jjMaxLength","6cm");
        Element test1 = root.addElement("test");
        test1.addAttribute("name","yi龙公子");
        test1.addAttribute("age","66");
        test1.addAttribute("jjMaxLength","7cm");
        Element test2 = root.addElement("test");
        test2.addAttribute("name","王有");
        test2.addAttribute("age","77");
        test2.addAttribute("jjMaxLength","1cm");
        try {
            OutputStream outputStream = response.getOutputStream();
            OutputFormat format = OutputFormat.createPrettyPrint();
            XMLWriter writer = new XMLWriter(outputStream, format);
            writer.write(document);
            writer.close();
            outputStream.flush();
            outputStream.close();
        } catch (FileNotFoundException | UnsupportedEncodingException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

用到的jar包：

xml"><!-- xml包 -->
        <dependency>
            <groupId>dom4j</groupId>
            <artifactId>dom4j</artifactId>
            <version>1.1</version>
        </dependency>