/**
   * {@inheritDoc}
   *
   * @param ctx
   */
  @Override
  public void prepareMarshal(GridCacheSharedContext ctx) throws IgniteCheckedException {
    super.prepareMarshal(ctx);

    if (ownedVals != null) {
      ownedValKeys = ownedVals.keySet();

      ownedValVals = ownedVals.values();

      for (Map.Entry<IgniteTxKey, CacheVersionedValue> entry : ownedVals.entrySet()) {
        GridCacheContext cacheCtx = ctx.cacheContext(entry.getKey().cacheId());

        entry.getKey().prepareMarshal(cacheCtx);

        entry.getValue().prepareMarshal(cacheCtx.cacheObjectContext());
      }
    }

    if (retVal != null && retVal.cacheId() != 0) {
      GridCacheContext cctx = ctx.cacheContext(retVal.cacheId());

      assert cctx != null : retVal.cacheId();

      retVal.prepareMarshal(cctx);
    }

    if (filterFailedKeys != null) {
      for (IgniteTxKey key : filterFailedKeys) {
        GridCacheContext cctx = ctx.cacheContext(key.cacheId());

        key.prepareMarshal(cctx);
      }
    }
  }
  /** Clears swap entries for evicted partition. */
  private void clearSwap() {
    assert state() == EVICTED;
    assert !GridQueryProcessor.isEnabled(cctx.config())
        : "Indexing needs to have unswapped values.";

    try {
      GridCloseableIterator<Map.Entry<byte[], GridCacheSwapEntry>> it = cctx.swap().iterator(id);

      boolean isLocStore = cctx.store().isLocal();

      if (it != null) {
        // We can safely remove these values because no entries will be created for evicted
        // partition.
        while (it.hasNext()) {
          Map.Entry<byte[], GridCacheSwapEntry> entry = it.next();

          byte[] keyBytes = entry.getKey();

          KeyCacheObject key = cctx.toCacheKeyObject(keyBytes);

          cctx.swap().remove(key);

          if (isLocStore) cctx.store().remove(null, key.value(cctx.cacheObjectContext(), false));
        }
      }
    } catch (IgniteCheckedException e) {
      U.error(log, "Failed to clear swap for evicted partition: " + this, e);
    }
  }
  /** Perform cleanup of the trash directory. */
  private void delete() {
    IgfsFileInfo info = null;

    try {
      info = meta.info(TRASH_ID);
    } catch (ClusterTopologyServerNotFoundException e) {
      LT.warn(log, e, "Server nodes not found.");
    } catch (IgniteCheckedException e) {
      U.error(log, "Cannot obtain trash directory info.", e);
    }

    if (info != null) {
      for (Map.Entry<String, IgfsListingEntry> entry : info.listing().entrySet()) {
        IgniteUuid fileId = entry.getValue().fileId();

        if (log.isDebugEnabled())
          log.debug(
              "Deleting IGFS trash entry [name=" + entry.getKey() + ", fileId=" + fileId + ']');

        try {
          if (!cancelled) {
            if (delete(entry.getKey(), fileId)) {
              if (log.isDebugEnabled())
                log.debug(
                    "Sending delete confirmation message [name="
                        + entry.getKey()
                        + ", fileId="
                        + fileId
                        + ']');

              sendDeleteMessage(new IgfsDeleteMessage(fileId));
            }
          } else break;
        } catch (IgniteInterruptedCheckedException ignored) {
          // Ignore this exception while stopping.
        } catch (IgniteCheckedException e) {
          U.error(log, "Failed to delete entry from the trash directory: " + entry.getKey(), e);

          sendDeleteMessage(new IgfsDeleteMessage(fileId, e));
        }
      }
    }
  }
  /**
   * Updates partition map in all caches.
   *
   * @param msg Partitions single message.
   */
  private void updatePartitionSingleMap(GridDhtPartitionsSingleMessage msg) {
    for (Map.Entry<Integer, GridDhtPartitionMap> entry : msg.partitions().entrySet()) {
      Integer cacheId = entry.getKey();
      GridCacheContext cacheCtx = cctx.cacheContext(cacheId);

      GridDhtPartitionTopology top =
          cacheCtx != null ? cacheCtx.topology() : cctx.exchange().clientTopology(cacheId, this);

      top.update(exchId, entry.getValue());
    }
  }
  /**
   * Updates partition map in all caches.
   *
   * @param msg Partitions full messages.
   */
  private void updatePartitionFullMap(GridDhtPartitionsFullMessage msg) {
    for (Map.Entry<Integer, GridDhtPartitionFullMap> entry : msg.partitions().entrySet()) {
      Integer cacheId = entry.getKey();

      GridCacheContext cacheCtx = cctx.cacheContext(cacheId);

      if (cacheCtx != null) cacheCtx.topology().update(exchId, entry.getValue());
      else {
        ClusterNode oldest = CU.oldestAliveCacheServerNode(cctx, AffinityTopologyVersion.NONE);

        if (oldest != null && oldest.isLocal())
          cctx.exchange().clientTopology(cacheId, this).update(exchId, entry.getValue());
      }
    }
  }
  /**
   * Starts activity.
   *
   * @throws IgniteInterruptedCheckedException If interrupted.
   */
  public void init() throws IgniteInterruptedCheckedException {
    if (isDone()) return;

    if (init.compareAndSet(false, true)) {
      if (isDone()) return;

      try {
        // Wait for event to occur to make sure that discovery
        // will return corresponding nodes.
        U.await(evtLatch);

        assert discoEvt != null : this;
        assert !dummy && !forcePreload : this;

        ClusterNode oldest = CU.oldestAliveCacheServerNode(cctx, exchId.topologyVersion());

        oldestNode.set(oldest);

        startCaches();

        // True if client node joined or failed.
        boolean clientNodeEvt;

        if (F.isEmpty(reqs)) {
          int type = discoEvt.type();

          assert type == EVT_NODE_JOINED || type == EVT_NODE_LEFT || type == EVT_NODE_FAILED
              : discoEvt;

          clientNodeEvt = CU.clientNode(discoEvt.eventNode());
        } else {
          assert discoEvt.type() == EVT_DISCOVERY_CUSTOM_EVT : discoEvt;

          boolean clientOnlyStart = true;

          for (DynamicCacheChangeRequest req : reqs) {
            if (!req.clientStartOnly()) {
              clientOnlyStart = false;

              break;
            }
          }

          clientNodeEvt = clientOnlyStart;
        }

        if (clientNodeEvt) {
          ClusterNode node = discoEvt.eventNode();

          // Client need to initialize affinity for local join event or for stated client caches.
          if (!node.isLocal()) {
            for (GridCacheContext cacheCtx : cctx.cacheContexts()) {
              if (cacheCtx.isLocal()) continue;

              GridDhtPartitionTopology top = cacheCtx.topology();

              top.updateTopologyVersion(exchId, this, -1, stopping(cacheCtx.cacheId()));

              if (cacheCtx.affinity().affinityTopologyVersion() == AffinityTopologyVersion.NONE) {
                initTopology(cacheCtx);

                top.beforeExchange(this);
              } else
                cacheCtx.affinity().clientEventTopologyChange(discoEvt, exchId.topologyVersion());
            }

            if (exchId.isLeft())
              cctx.mvcc().removeExplicitNodeLocks(exchId.nodeId(), exchId.topologyVersion());

            onDone(exchId.topologyVersion());

            skipPreload = cctx.kernalContext().clientNode();

            return;
          }
        }

        if (cctx.kernalContext().clientNode()) {
          skipPreload = true;

          for (GridCacheContext cacheCtx : cctx.cacheContexts()) {
            if (cacheCtx.isLocal()) continue;

            GridDhtPartitionTopology top = cacheCtx.topology();

            top.updateTopologyVersion(exchId, this, -1, stopping(cacheCtx.cacheId()));
          }

          for (GridCacheContext cacheCtx : cctx.cacheContexts()) {
            if (cacheCtx.isLocal()) continue;

            initTopology(cacheCtx);
          }

          if (oldestNode.get() != null) {
            rmtNodes =
                new ConcurrentLinkedQueue<>(
                    CU.aliveRemoteServerNodesWithCaches(cctx, exchId.topologyVersion()));

            rmtIds = Collections.unmodifiableSet(new HashSet<>(F.nodeIds(rmtNodes)));

            ready.set(true);

            initFut.onDone(true);

            if (log.isDebugEnabled()) log.debug("Initialized future: " + this);

            sendPartitions();
          } else onDone(exchId.topologyVersion());

          return;
        }

        assert oldestNode.get() != null;

        for (GridCacheContext cacheCtx : cctx.cacheContexts()) {
          if (isCacheAdded(cacheCtx.cacheId(), exchId.topologyVersion())) {
            if (cacheCtx
                .discovery()
                .cacheAffinityNodes(cacheCtx.name(), topologyVersion())
                .isEmpty())
              U.quietAndWarn(log, "No server nodes found for cache client: " + cacheCtx.namex());
          }

          cacheCtx.preloader().onExchangeFutureAdded();
        }

        List<String> cachesWithoutNodes = null;

        if (exchId.isLeft()) {
          for (String name : cctx.cache().cacheNames()) {
            if (cctx.discovery().cacheAffinityNodes(name, topologyVersion()).isEmpty()) {
              if (cachesWithoutNodes == null) cachesWithoutNodes = new ArrayList<>();

              cachesWithoutNodes.add(name);

              // Fire event even if there is no client cache started.
              if (cctx.gridEvents().isRecordable(EventType.EVT_CACHE_NODES_LEFT)) {
                Event evt =
                    new CacheEvent(
                        name,
                        cctx.localNode(),
                        cctx.localNode(),
                        "All server nodes have left the cluster.",
                        EventType.EVT_CACHE_NODES_LEFT,
                        0,
                        false,
                        null,
                        null,
                        null,
                        null,
                        false,
                        null,
                        false,
                        null,
                        null,
                        null);

                cctx.gridEvents().record(evt);
              }
            }
          }
        }

        if (cachesWithoutNodes != null) {
          StringBuilder sb =
              new StringBuilder(
                  "All server nodes for the following caches have left the cluster: ");

          for (int i = 0; i < cachesWithoutNodes.size(); i++) {
            String cache = cachesWithoutNodes.get(i);

            sb.append('\'').append(cache).append('\'');

            if (i != cachesWithoutNodes.size() - 1) sb.append(", ");
          }

          U.quietAndWarn(log, sb.toString());

          U.quietAndWarn(log, "Must have server nodes for caches to operate.");
        }

        assert discoEvt != null;

        assert exchId.nodeId().equals(discoEvt.eventNode().id());

        for (GridCacheContext cacheCtx : cctx.cacheContexts()) {
          GridClientPartitionTopology clientTop =
              cctx.exchange().clearClientTopology(cacheCtx.cacheId());

          long updSeq = clientTop == null ? -1 : clientTop.lastUpdateSequence();

          // Update before waiting for locks.
          if (!cacheCtx.isLocal())
            cacheCtx
                .topology()
                .updateTopologyVersion(exchId, this, updSeq, stopping(cacheCtx.cacheId()));
        }

        // Grab all alive remote nodes with order of equal or less than last joined node.
        rmtNodes =
            new ConcurrentLinkedQueue<>(
                CU.aliveRemoteServerNodesWithCaches(cctx, exchId.topologyVersion()));

        rmtIds = Collections.unmodifiableSet(new HashSet<>(F.nodeIds(rmtNodes)));

        for (Map.Entry<UUID, GridDhtPartitionsSingleMessage> m : singleMsgs.entrySet())
          // If received any messages, process them.
          onReceive(m.getKey(), m.getValue());

        for (Map.Entry<UUID, GridDhtPartitionsFullMessage> m : fullMsgs.entrySet())
          // If received any messages, process them.
          onReceive(m.getKey(), m.getValue());

        AffinityTopologyVersion topVer = exchId.topologyVersion();

        for (GridCacheContext cacheCtx : cctx.cacheContexts()) {
          if (cacheCtx.isLocal()) continue;

          // Must initialize topology after we get discovery event.
          initTopology(cacheCtx);

          cacheCtx.preloader().updateLastExchangeFuture(this);
        }

        IgniteInternalFuture<?> partReleaseFut = cctx.partitionReleaseFuture(topVer);

        // Assign to class variable so it will be included into toString() method.
        this.partReleaseFut = partReleaseFut;

        if (log.isDebugEnabled()) log.debug("Before waiting for partition release future: " + this);

        while (true) {
          try {
            partReleaseFut.get(2 * cctx.gridConfig().getNetworkTimeout(), TimeUnit.MILLISECONDS);

            break;
          } catch (IgniteFutureTimeoutCheckedException ignored) {
            // Print pending transactions and locks that might have led to hang.
            dumpPendingObjects();
          }
        }

        if (log.isDebugEnabled()) log.debug("After waiting for partition release future: " + this);

        if (!F.isEmpty(reqs)) blockGateways();

        if (exchId.isLeft())
          cctx.mvcc().removeExplicitNodeLocks(exchId.nodeId(), exchId.topologyVersion());

        IgniteInternalFuture<?> locksFut = cctx.mvcc().finishLocks(exchId.topologyVersion());

        while (true) {
          try {
            locksFut.get(2 * cctx.gridConfig().getNetworkTimeout(), TimeUnit.MILLISECONDS);

            break;
          } catch (IgniteFutureTimeoutCheckedException ignored) {
            U.warn(
                log,
                "Failed to wait for locks release future. "
                    + "Dumping pending objects that might be the cause: "
                    + cctx.localNodeId());

            U.warn(log, "Locked entries:");

            Map<IgniteTxKey, Collection<GridCacheMvccCandidate>> locks =
                cctx.mvcc().unfinishedLocks(exchId.topologyVersion());

            for (Map.Entry<IgniteTxKey, Collection<GridCacheMvccCandidate>> e : locks.entrySet())
              U.warn(log, "Locked entry [key=" + e.getKey() + ", mvcc=" + e.getValue() + ']');
          }
        }

        for (GridCacheContext cacheCtx : cctx.cacheContexts()) {
          if (cacheCtx.isLocal()) continue;

          // Notify replication manager.
          GridCacheContext drCacheCtx =
              cacheCtx.isNear() ? cacheCtx.near().dht().context() : cacheCtx;

          if (drCacheCtx.isDrEnabled()) drCacheCtx.dr().beforeExchange(topVer, exchId.isLeft());

          // Partition release future is done so we can flush the write-behind store.
          cacheCtx.store().forceFlush();

          // Process queued undeploys prior to sending/spreading map.
          cacheCtx.preloader().unwindUndeploys();

          GridDhtPartitionTopology top = cacheCtx.topology();

          assert topVer.equals(top.topologyVersion())
              : "Topology version is updated only in this class instances inside single ExchangeWorker thread.";

          top.beforeExchange(this);
        }

        for (GridClientPartitionTopology top : cctx.exchange().clientTopologies()) {
          top.updateTopologyVersion(exchId, this, -1, stopping(top.cacheId()));

          top.beforeExchange(this);
        }
      } catch (IgniteInterruptedCheckedException e) {
        onDone(e);

        throw e;
      } catch (Throwable e) {
        U.error(
            log,
            "Failed to reinitialize local partitions (preloading will be stopped): " + exchId,
            e);

        onDone(e);

        if (e instanceof Error) throw (Error) e;

        return;
      }

      if (F.isEmpty(rmtIds)) {
        onDone(exchId.topologyVersion());

        return;
      }

      ready.set(true);

      initFut.onDone(true);

      if (log.isDebugEnabled()) log.debug("Initialized future: " + this);

      // If this node is not oldest.
      if (!oldestNode.get().id().equals(cctx.localNodeId())) sendPartitions();
      else {
        boolean allReceived = allReceived();

        if (allReceived && replied.compareAndSet(false, true)) {
          if (spreadPartitions()) onDone(exchId.topologyVersion());
        }
      }

      scheduleRecheck();
    } else assert false : "Skipped init future: " + this;
  }
  /**
   * Remove particular entry from the trash directory or subdirectory.
   *
   * @param parentId Parent ID.
   * @param id Entry id.
   * @throws IgniteCheckedException If delete failed for some reason.
   */
  private void deleteDirectory(IgniteUuid parentId, IgniteUuid id) throws IgniteCheckedException {
    assert parentId != null;
    assert id != null;

    while (true) {
      IgfsFileInfo info = meta.info(id);

      if (info != null) {
        assert info.isDirectory();

        Map<String, IgfsListingEntry> listing = info.listing();

        if (listing.isEmpty()) return; // Directory is empty.

        Map<String, IgfsListingEntry> delListing;

        if (listing.size() <= MAX_DELETE_BATCH) delListing = listing;
        else {
          delListing = new HashMap<>(MAX_DELETE_BATCH, 1.0f);

          int i = 0;

          for (Map.Entry<String, IgfsListingEntry> entry : listing.entrySet()) {
            delListing.put(entry.getKey(), entry.getValue());

            if (++i == MAX_DELETE_BATCH) break;
          }
        }

        GridCompoundFuture<Object, ?> fut = new GridCompoundFuture<>();

        // Delegate to child folders.
        for (IgfsListingEntry entry : delListing.values()) {
          if (!cancelled) {
            if (entry.isDirectory()) deleteDirectory(id, entry.fileId());
            else {
              IgfsFileInfo fileInfo = meta.info(entry.fileId());

              if (fileInfo != null) {
                assert fileInfo.isFile();

                fut.add(data.delete(fileInfo));
              }
            }
          } else return;
        }

        fut.markInitialized();

        // Wait for data cache to delete values before clearing meta cache.
        try {
          fut.get();
        } catch (IgniteFutureCancelledCheckedException ignore) {
          // This future can be cancelled only due to IGFS shutdown.
          cancelled = true;

          return;
        }

        // Actual delete of folder content.
        Collection<IgniteUuid> delIds = meta.delete(id, delListing);

        if (delListing == listing && delListing.size() == delIds.size())
          break; // All entries were deleted.
      } else break; // Entry was deleted concurrently.
    }
  }