public void write(OutputStream output) throws IOException,
            ServiceFormattedException {
          FSDataInputStream in = null;
          for (String path : request.entries) {
            try {
              try {
                in = getApi().open(path);
              } catch (AccessControlException ex) {
                LOG.error("Error in opening file {}. Ignoring concat of this files.", path.substring(1), ex);
                continue;
              }

              long bytesCopied = IOUtils.copyLarge(in, output);
              LOG.info("concated file : {}, total bytes added = {}", path, bytesCopied);
            } catch (Exception ex) {
              LOG.error("Error occurred : ", ex);
              throw new ServiceFormattedException(ex.getMessage(), ex);
            } finally {
              if (in != null)
                in.close();
            }
          }
        }
Concatenate files
@param request download request
@return response with all files concatenated
contrib/views/files/src/main/java/org/apache/ambari/view/filebrowser/DownloadService.java