docs: public static boolean readFullyOrNothing(InputStream in, byte[] buffer) throws IOException {
          int bytesRead = 0;
          do {
              int count = in.read(buffer, bytesRead, buffer.length - bytesRead);
              if (count < 0) {
                  if (bytesRead == 0) {
                      return false;
                  }
                  throw new EOFException();
              }
              bytesRead += count;
          } while (bytesRead < buffer.length);
          return true;
      }