/** @return Nodes to execute on. */
  private Collection<ClusterNode> nodes() {
    CacheMode cacheMode = cctx.config().getCacheMode();

    switch (cacheMode) {
      case LOCAL:
        if (prj != null)
          U.warn(
              log,
              "Ignoring query projection because it's executed over LOCAL cache "
                  + "(only local node will be queried): "
                  + this);

        return Collections.singletonList(cctx.localNode());

      case REPLICATED:
        if (prj != null || partition() != null) return nodes(cctx, prj, partition());

        return cctx.affinityNode()
            ? Collections.singletonList(cctx.localNode())
            : Collections.singletonList(F.rand(nodes(cctx, null, partition())));

      case PARTITIONED:
        return nodes(cctx, prj, partition());

      default:
        throw new IllegalStateException("Unknown cache distribution mode: " + cacheMode);
    }
  }
  /**
   * Processes cache query response.
   *
   * @param sndId Sender node id.
   * @param res Query response.
   */
  @SuppressWarnings("unchecked")
  private void processQueryResponse(UUID sndId, GridCacheQueryResponse res) {
    if (log.isDebugEnabled()) log.debug("Received query response: " + res);

    GridCacheQueryFutureAdapter fut = getQueryFuture(res.requestId());

    if (fut != null)
      if (res.fields())
        ((GridCacheDistributedFieldsQueryFuture) fut)
            .onPage(
                sndId,
                res.metadata(),
                (Collection<Map<String, Object>>) ((Collection) res.data()),
                res.error(),
                res.isFinished());
      else fut.onPage(sndId, res.data(), res.error(), res.isFinished());
    else if (!cancelled.contains(res.requestId()))
      U.warn(
          log,
          "Received response for finished or unknown query [rmtNodeId="
              + sndId
              + ", res="
              + res
              + ']');
  }