code: public static OutputStream bytes2OutputStream(final byte[] bytes) {
          if (bytes == null || bytes.length <= 0) return null;
          ByteArrayOutputStream os = null;
          try {
              os = new ByteArrayOutputStream();
              os.write(bytes);
              return os;
          } catch (IOException e) {
              e.printStackTrace();
              return null;
          } finally {
              IOKit.closeQuietly(os);
          }
      }
docs: outputStream转byteArr
  
  @param bytes 字节数组
  @return 字节数组