docs: public static long copy(final InputStream in, final OutputStream out) throws IOException {
  		long length = 0;
  		final byte[] b = new byte[IO_BUFFER_SIZE];
  		int read;
  		while ((read = in.read(b)) != -1) {
  			out.write(b, 0, read);
  			length += read;
  		}
  		return length;
  	}