docs: public void renew(final Txn<T> newTxn) {
      if (SHOULD_CHECK) {
        requireNonNull(newTxn);
        checkNotClosed();
        this.txn.checkReadOnly(); // existing
        newTxn.checkReadOnly();
        newTxn.checkReady();
      }
      checkRc(LIB.mdb_cursor_renew(newTxn.pointer(), ptrCursor));
      this.txn = newTxn;
    }