Fastdfs读取文件内容

String txtId = vo.getTxtId();
if(txtId!=null){
     OkHttpClient httpClient = new OkHttpClient();
     Request request = new Request.Builder().url(FASTDFS_URL+txtId).build();
     Response response = null;
     try {
        response = httpClient.newCall(request).execute();
        vo.setTxtId(response.body().string());
     } catch (IOException e) {
        e.printStackTrace();
     }
 }