Android-SDK之如何实现下载文件（一）?

简单下载


下载指定文件，下载后将获得文件的输入流，此操作要求用户对该Object有读权限。同步调用：

1. // 构造下载文件请求
2. GetObjectRequest get = new GetObjectRequest("<bucketName>", "<objectKey>");
4. try {
5.     // 同步执行下载请求，返回结果
6.     GetObjectResult getResult = oss.getObject(get);
8.     Log.d("Content-Length", "" + getResult.getContentLength());
10.     // 获取文件输入流
11.     InputStream inputStream = getResult.getObjectContent();
13.     byte[] buffer = new byte[2048];
14.     int len;
16.     while ((len = inputStream.read(buffer)) != -1) {
17.         // 处理下载的数据，比如图片展示或者写入文件等
18.     }
20.     // 下载后可以查看文件元信息
21.     ObjectMetadata metadata = getResult.getMetadata();
22.     Log.d("ContentType", metadata.getContentType());
25. } catch (ClientException e) {
26.     // 本地异常如网络异常等
27.     e.printStackTrace();
28. } catch (ServiceException e) {
29.     // 服务异常
30.     Log.e("RequestId", e.getRequestId());
31.     Log.e("ErrorCode", e.getErrorCode());
32.     Log.e("HostId", e.getHostId());
33.     Log.e("RawMessage", e.getRawMessage());
34. } catch (IOException e) {
35.     e.printStackTrace();
36. }

1. GetObjectRequest get = new GetObjectRequest("<bucketName>", "<objectKey>");
3. OSSAsyncTask task = oss.asyncGetObject(get, new OSSCompletedCallback<GetObjectRequest, GetObjectResult>() {
4.     @Override
5.     public void onSuccess(GetObjectRequest request, GetObjectResult result) {
6.         // 请求成功
7.         InputStream inputStream = result.getObjectContent();
9.         byte[] buffer = new byte[2048];
10.         int len;
12.         try {
13.             while ((len = inputStream.read(buffer)) != -1) {
14.                 // 处理下载的数据
15.             }
16.         } catch (IOException e) {
17.             e.printStackTrace();
18.         }
19.     }
21.     @Override
22.     public void onFailure(GetObjectRequest request, ClientException clientExcepion, ServiceException serviceException) {
23.         // 请求异常
24.         if (clientExcepion != null) {
25.             // 本地异常如网络异常等
26.             clientExcepion.printStackTrace();
27.         }
28.         if (serviceException != null) {
29.             // 服务异常
30.             Log.e("ErrorCode", serviceException.getErrorCode());
31.             Log.e("RequestId", serviceException.getRequestId());
32.             Log.e("HostId", serviceException.getHostId());
33.             Log.e("RawMessage", serviceException.getRawMessage());
34.         }
35.     }
36. });