FastDFS的配置、部署与API使用解读（3）以流的方式上传文件的客户端代码（转）

调用的API为：

String[] upload_file(

String group_name,//组名，不指定则可设为null

long file_size,//文件大小，必须制定

UploadCallback callback,//回调

String file_ext_name,

NameValuePair[] meta_list

)

     /**
      * Upload File to DFS, directly transferring java.io.InputStream to java.io.OutStream
      * @author Poechant
      * @email zhongchao.ustc@gmail.com
      * @param fileBuff, file to be uploaded.
      * @param uploadFileName, the name of the file.
      * @param fileLength, the length of the file.
      * @return the file ID in DFS.
      * @throws IOException
      */
     public String[] uploadFileByStream(InputStream inStream, String uploadFileName, long fileLength) throws IOException {  

         String[] results = null;
         String fileExtName = "";
         if (uploadFileName.contains(".")) {
             fileExtName = uploadFileName.substring(uploadFileName.lastIndexOf(".") + );
         } else {
             logger.warn("Fail to upload file, because the format of filename is illegal.");
             return results;
         }  

         TrackerClient tracker = new TrackerClient();
            TrackerServer trackerServer = tracker.getConnection();
            StorageServer storageServer = null;
            StorageClient1 client = new StorageClient1(trackerServer, storageServer);  

            NameValuePair[] metaList = new NameValuePair[];
            metaList[] = new NameValuePair("fileName", uploadFileName);
            metaList[] = new NameValuePair("fileExtName", fileExtName);
            metaList[] = new NameValuePair("fileLength", String.valueOf(fileLength));  

            try {
             // results[0]: groupName, results[1]: remoteFilename.
             results = client.upload_file(null, fileLength, new UploadFileSender(inStream), fileExtName, metaList);
         } catch (Exception e) {
             logger.warn("Upload file \"" + uploadFileName + "\"fails");
         }  

             trackerServer.close();  

         return results;
     }  

其中的UploadFileSender是一个实现了UploadCallback接口的类：

     private static class UploadFileSender implements UploadCallback {  

         private InputStream inStream;  

         public UploadFileSender(InputStream inStream) {
             this.inStream = inStream;
         }  

         public int send(OutputStream out) throws IOException {
             int readBytes;
             while((readBytes = inStream.read()) > ) {
                 out.write(readBytes);
             }
             return ;
         }
     }