code: private void handleEmptySelects() {
      getLogger().debug("No selectors ready, interrupted: %b",
        Thread.interrupted());
  
      if (++emptySelects > DOUBLE_CHECK_EMPTY) {
        for (SelectionKey sk : selector.keys()) {
          getLogger().debug("%s has %s, interested in %s", sk, sk.readyOps(),
            sk.interestOps());
          if (sk.readyOps() != 0) {
            getLogger().debug("%s has a ready op, handling IO", sk);
            handleIO(sk);
          } else {
            lostConnection((MemcachedNode) sk.attachment());
          }
        }
        assert emptySelects < EXCESSIVE_EMPTY : "Too many empty selects";
      }
    }
docs: Helper method for {@link #handleIO()} to handle empty select calls.