/**
     * 通过文件路径下载文件
     *
     * @param filePath 文件路径
     * @param response
     * @throws Exception
     */
    public int download(String filePath, String attachmentName,HttpServletResponse response) throws Exception {
        // 判断文件是否存在
        File file = new File(filePath);
        logger.info("DOWNLOAD PATH：" + filePath);
        if (!file.exists() || file.isDirectory()) {
            logger.info("FILE DOES NOT EXIST！");
            return 0;
        }
        // 自定义文件名
        String filename = file.getAbsolutePath();
        String suffix = filename.substring(filename.lastIndexOf("."));
        //根据UUID重命名文件
        // String attachmentName = IdUtils.getId() + suffix;
        response.setHeader("content-disposition", "attachment;filename=" + URLEncoder.encode(attachmentName, "UTF-8"));
        InputStream in = null;
        BufferedInputStream bis = null;
        OutputStream out = null;
        BufferedOutputStream bos = null;
        try {
            in = new FileInputStream(filePath);
            bis = new BufferedInputStream(in);
            byte[] data = new byte[1024];
            int bytes = 0;
            out = response.getOutputStream();
            bos = new BufferedOutputStream(out);
            while ((bytes = bis.read(data, 0, data.length)) != -1) {
                bos.write(data, 0, bytes);
            }
            bos.flush();
            return 1;
        } catch (Exception e) {
            logger.error("THE REQUEST FAILED：" + e.getMessage(), e);
            throw new Exception("THE REQUEST FAILED！");
        } finally {
            try {
                if (bos != null) {
                    bos.close();
                }
                if (out != null) {
                    out.close();
                }
                if (bis != null) {
                    bis.close();
                }
                if (in != null) {
                    in.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }


    /**
     * 下载文件
     *
     * @param path 文件的位置
     * @param fileName 自定义下载文件的名称
     * @param resp http响应
     * @param req http请求
     */

    // 字符编码格式
    private static String charsetCode = "utf-8";

    public static int downloadFile(String path, String fileName, HttpServletResponse resp, HttpServletRequest req) {

        int i;
        try {
            File file = new File(path);
            /**
             * 中文乱码解决
             */
            String type = req.getHeader("User-Agent").toLowerCase();
            if (type.indexOf("firefox") > 0 || type.indexOf("chrome") > 0) {
                /**
                 * 谷歌或火狐
                 */
                fileName = new String(fileName.getBytes(charsetCode), "iso8859-1");
            } else {
                /**
                 * IE
                 */
                fileName = URLEncoder.encode(fileName, charsetCode);
            }
            // 设置响应的头部信息
            resp.setHeader("content-disposition", "attachment;filename=" + fileName);
            // 设置响应内容的类型
            resp.setContentType(getFileContentType(fileName) + "; charset=" + charsetCode);
            // 设置响应内容的长度
            resp.setContentLength((int) file.length());
            // 输出
            outStream(new FileInputStream(file), resp.getOutputStream());
            i = 1;
        } catch (Exception e) {
            System.out.println("执行downloadFile发生了异常：" + e.getMessage());
            i = 0;
        }
        return i;
    }

    /**
     * 文件的内容类型
     */
    private static String getFileContentType(String name) {
        String result = "";
        String fileType = name.toLowerCase();
        if (fileType.endsWith(".png")) {
            result = "image/png";
        } else if (fileType.endsWith(".gif")) {
            result = "image/gif";
        } else if (fileType.endsWith(".jpg") || fileType.endsWith(".jpeg")) {
            result = "image/jpeg";
        } else if (fileType.endsWith(".svg")) {
            result = "image/svg+xml";
        } else if (fileType.endsWith(".doc")) {
            result = "application/msword";
        } else if (fileType.endsWith(".xls")) {
            result = "application/x-excel";
        } else if (fileType.endsWith(".zip")) {
            result = "application/zip";
        } else if (fileType.endsWith(".pdf")) {
            result = "application/pdf";
        } else {
            result = "application/octet-stream";
        }
        return result;
    }

    /**
     * 基础字节数组输出
     */
    private static void outStream(InputStream is, OutputStream os) {
        try {
            byte[] buffer = new byte[10240];
            int length = -1;
            while ((length = is.read(buffer)) != -1) {
                os.write(buffer, 0, length);
                os.flush();
            }
        } catch (Exception e) {
            System.out.println("执行 outStream 发生了异常：" + e.getMessage());
        } finally {
            try {
                os.close();
            } catch (IOException e) {
            }
            try {
                is.close();
            } catch (IOException e) {
            }
        }
    }

    /**
     * 从网络Url中下载文件
     *
     * @param urlStr
     * @param fileName
     * @param savePath
     * @throws IOException
     */

    public static int downLoadFromUrl(String urlStr, String fileName, String savePath) {

        try {
            URL url = new URL(urlStr);
            HttpURLConnection conn = (HttpURLConnection) url.openConnection();
            // 设置超时间为3秒
            conn.setConnectTimeout(3 * 1000);
            // 防止屏蔽程序抓取而返回403错误
            conn.setRequestProperty("User-Agent", "Mozilla/4.0 (compatible; MSIE 5.0; Windows NT; DigExt)");
            // 得到输入流
            InputStream inputStream = conn.getInputStream();
            // 获取自己数组
            byte[] getData = readInputStream(inputStream);
            // 文件保存位置
            File saveDir = new File(savePath);
            if (!saveDir.exists()) {
                saveDir.mkdir();
            }

            File file = new File(saveDir + File.separator + fileName);
            FileOutputStream fos = new FileOutputStream(file);
            fos.write(getData);
            if (fos != null) {
                fos.close();
            }
            if (inputStream != null) {
                inputStream.close();
            }
            // System.out.println("info:"+url+" download success");
            // return saveDir + File.separator + fileName;
            return 1;
        } catch (Exception e) {
            e.printStackTrace();
        }
        return 0;
    }


    /**
     * 从输入流中获取字节数组
     *
     * @param inputStream
     * @return
     * @throws IOException
     */

    public static byte[] readInputStream(InputStream inputStream) throws IOException {

        byte[] buffer = new byte[1024];

        int len = 0;

        ByteArrayOutputStream bos = new ByteArrayOutputStream();

        while ((len = inputStream.read(buffer)) != -1) {

            bos.write(buffer, 0, len);

        }

        bos.close();

        return bos.toByteArray();

    }


 public void getFile(HttpServletResponse response,String localMapJsonPath, String fileName) throws Exception {
        File localMapJsonDir = new File(localMapJsonPath);
        if (!localMapJsonDir.exists()) {
            throw new Exception("文件夹不存在: " + localMapJsonPath);
        }
        String filePath = localMapJsonPath + "/" + fileName;
        File file = new File(filePath);
        InputStream inputStream = null;
        if (!file.exists()) {
            throw new Exception("文件不存在: " + filePath);
        }

        ServletOutputStream outputStream = response.getOutputStream();
        try {
            inputStream = new FileInputStream(file);
            byte[] buf = new byte[1024];
            int readLength = inputStream.read(buf);
            while (readLength != -1) {
                outputStream.write(buf, 0, readLength);
                readLength = inputStream.read(buf);
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            if (outputStream != null) {
                try {
                    outputStream.flush();
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
            IOUtils.closeQuietly(outputStream);
            IOUtils.closeQuietly(inputStream);
        }
    }

以上方法自行测试！！！

以下是我自己测试成功的例子（仅供参考）：

后台

  @RequestMapping("/downloadMylData")
    public void downloadMylData(@RequestParam(name = "type") String type,
                                @RequestParam(name = "time") String time,
                                @RequestParam(name = "eleName") String eleName,
                                @RequestParam(name = "ybSection") String ybSection,
                                @RequestParam(name = "timeNode") String timeNode,
                                HttpServletResponse response) throws Exception {
        // String sql = "SELECT\n" +
        //         "\tSRC\n" +
        //         "FROM\n" +
        //         "\tTASK_DATA_SAVE\n" +
        //         "WHERE\n" +
        //         "\tMODULETYPE = '" + type + "'\n" +
        //         "AND STARTTIME = '" + time + "'\n" +
        //         "AND ELETYPE = '" + eleName + "'\n" +
        //         "AND AGING = '" + timeNode + "'\n" +
        //         "AND SCALE = '" + ybSection + "'";
        //
        // List<Map<String, Object>> maps = priJdbcTemplate.queryForList(sql);
        // String filePath = null;
        // if (maps != null && maps.size() > 0) {
        //     filePath = maps.get(0).get("SRC").toString();
        // } else {
        //     logger.info("无此文件路径");
        //     return;
        // }
        // String fileName = filePath.split("\\\\")[6] + "-" + filePath.split("\\\\")[7] + "-" + filePath.split("\\\\")[8];

      /*  String localPath = "D:/downloadFile/" + filePath.split("\\\\")[6] + "-" + filePath.split("\\\\")[7];
        File localFile = new File(localPath);
        if (!localFile.exists()) {
            localFile.mkdirs();
        }*/
        // //本地测试
        String filePath = "C:\\Users\\84695\\Desktop\\GDS\\ECMWF_HR\\RAIN24\\19061408.024";
        String fileName = "ECMWF_HR-RAIN24-19061408.024";
        boolean flag = downFile(fileName, response, filePath);

        if (flag) {
            logger.info(fileName + "文件下载成功！");
        } else {
            logger.info("文件下载失败");
        }
    }

 /**
     * 描述: 下载资料
     *
     * @author: css
     * @create: 2019/10/17 14:00
     */
    public boolean downFile(String fileName, HttpServletResponse response, String filePath) {
        boolean flag = false;
        File file = new File(filePath);
        if (file.exists()) {
            // String[] split = filePath.split("\\\\");
            response.setContentType("application/force-download");// 设置强制下载不打开
            try {
                response.addHeader("Content-Disposition", "attachment;fileName=" + URLEncoder.encode(fileName + ".zip", "UTF-8"));
            } catch (UnsupportedEncodingException e) {
                e.printStackTrace();
            }
            byte[] buffer = new byte[1024];
            FileInputStream fis = null;
            BufferedInputStream bis = null;
            try {
                fis = new FileInputStream(file);
                bis = new BufferedInputStream(fis);
                OutputStream outputStream = response.getOutputStream();
                int i = bis.read(buffer);
                while (i != -1) {
                    outputStream.write(buffer, 0, i);
                    i = bis.read(buffer);
                }
                // return true;
                flag = true;
            } catch (Exception e) {
                e.printStackTrace();
            } finally {
                if (bis != null) {
                    try {
                        bis.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
                if (fis != null) {
                    try {
                        fis.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
            }
        }
        return flag;
    }

前台

<div class="index-form" id="index-operation-btn">
            <a href="javascript:void(0);" class="btn btn-xs btn-default" name="下载资料" id="myDownload" style="margin-top: 5px;">下载资料</a>
        </div>

  /*点击下载资料按钮*/
    downloadMylData: function () {
        $('#index-operation-btn a[name="下载资料"]').click(function () {
            var self = this;
            var title = $(".index-map-title b").text();
            var titleArray = title.split("-");

            var type = $('#index-moduleTpe-select option:selected').val();  // 数据的类型
            var time = titleArray[2];
            var eleName = 'RAIN';
            var ybSection = titleArray[1].split("RAIN")[1];
            var timeNode = titleArray[3];

            //本地
            $('#index-operation-btn a[name="下载资料"]').attr('href', "http://localhost:7777/downloadMyData?type="+type+"&time="+time+"&eleName="+eleName+"&ybSection="+ybSection+"&timeNode="+timeNode);
        });

          // 这个也可以
          // window.location.href = "http://localhost:7777/CJLY3/gridCW/downloadMylData?type=" +
              //  type + "&time=" + time + "&eleName="+ eleName + "&ybSection=" + ybSection + "&timeNode=" + timeNode;
    },

能触发浏览器下载的url有两类:

1. response header——指定了Content-Disposition为attachment，它表示让浏览器把响应体作为附件下载到本地 (一般Content-Disposition还会指定filename, 下载的文件默认就是filename指定的名字)
2. response header——指定了Content-Type 为 application/octet-stream(无类型) 或者application/zip(下载zip包时)以及其它几个不常见类型 (其中还有浏览器差异)，其中 application/octet-stream表示http response为二进制流(没指定明确的type), 需要下载到本地, 由系统决定或者用户手动指定打开方式。