code: public void reset() {
          synchronized (zsRef) {
              ensureOpen();
              reset(zsRef.address());
              finish = false;
              finished = false;
              off = len = 0;
              bytesRead = bytesWritten = 0;
          }
      }
docs: Resets deflater so that a new set of input data can be processed.
  Keeps current compression level and strategy settings.