一 流的转换

    /**
     * 获取流
     * @param
     * @param bucketName
     * @param objectKey
     */
    @Override
    public void getViewStream(HttpServletResponse response, String bucketName, String objectKey) {
        AmazonS3 s3 = oosUtils.getAmazonS3();
        try {
            GetObjectRequest getObjectRequest = new GetObjectRequest(bucketName, objectKey);
            S3Object o = s3.getObject(getObjectRequest);
            S3ObjectInputStream s3is = o.getObjectContent();
            response.setContentType("video/mp4");
            response.addHeader("Content-Type", "audio/mp4;charset=UTF-8");
            IOUtils.copy(s3is, response.getOutputStream());
            response.flushBuffer();
        }
        catch (AmazonServiceException | IOException e) {
            System.err.println(e.getMessage());
        }
    }