xml或其他附件下载到客户端

//xml
                Document document=DocumentHelper.createDocument();
                Element root=document.addElement("root");

//。。。。。省略document的过程。。。。。

//下载到指定目录
OutputFormat format=OutputFormat.createPrettyPrint();
                format.setEncoding("UTF-8");
                XMLWriter writer=new XMLWriter(new FileOutputStream(new File("D://dzoa.xml")),format);
                writer.write(document);
                writer.close();

//下载到客户端
DownloadTool.doReady(response, "application/octet-stream", 0, "dzoa.xml");
                XMLWriter writer=new XMLWriter(response.getOutputStream(), OutputFormat.createPrettyPrint());
                writer.write(document);
　　　　　　　　　writer.close();

//相关方法代码
  /**
     * @param mimeType 文件的mime-type，如为null或空字符串，就取multipart/form-data
     * @param filelen  文件长度，大于0表示真实长度，0或负值表示unknown
     * @param fileName 文件名称
     * @param inline   可选项，是inline还是attachment，默认false
     */
    public static void doReady(HttpServletResponse response, String mimeType, long filelen, String fileName, boolean... inline) {
        if (mimeType == null || mimeType.isEmpty()) mimeType = "multipart/form-data";
        fileName = rawEncode(fileName); // RFC 3986

        response.setCharacterEncoding("UTF-8");
        response.setContentType(mimeType);
        if (filelen > 0) response.setHeader("Content-Length", String.valueOf(filelen));

        // firefox: filename*=utf-8''
        // IE or chrome: filename= or filename*=utf-8''
        // Xunlei: filename= or filename*=utf-8''
        response.setHeader("Content-Disposition", ((inline.length > 0 && inline[0]) ? "inline" : "attachment") + "; filename=\"" + fileName + "\"" + "; filename*=utf-8''" + fileName);
    }

------------------------------------一般情况的下载附件可调用下列方法-------------------------

   /**
     * @param mimeType 文件的mime-type，如为null或空字符串，就取multipart/form-data
     * @param data     数据
     * @param fileName 文件名称
     * @param inline   可选项，是inline还是attachment，默认false
     */
    public static void download(HttpServletResponse response, String mimeType, byte[] data, String fileName, boolean... inline) {
        response.reset();
        doReady(response, mimeType, (long) data.length, fileName, inline);

        OutputStream os = null;
        try {
            os = response.getOutputStream();
            os.write(data);
            os.flush();
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            close(os);
        }
    }

-----------------------------------如果客户端还是没有出来附件下载，检查一下代码---------------------------------------

 //数据导出
     function gwExport(){
         top.$.fn._confirm("确认要导出数据吗？", function(i){
             if(1 == i){
                 var cVal = "";
                 var cValStr=[];
                 $("#myTable td input[name=fileCheck]").each(function(){
                     if(this.checked){
                        cValStr.push($(this).val());
                     }
                 });
                 cVal=cValStr.join(",");
                 if(cVal==""){
                     top.$.fn._alert("请选择需要导出的公文。");
                     return;
                 }

                 //alert(cVal);
                 location.href = "${ctx}/oa/myflow/procinst/gwExport?" + $.param({"pInsIds": cVal});
                 /* $.post("${ctx}/oa/myflow/procinst/gwExport", {"pInsIds": cVal}, function(data){
                     top.$.fn._alert(data.info);
                     if(data.state==1){
                        // location.reload();
                     }
                 }); */
             }
         });
     }