/**
   * @param updateSeq Update sequence.
   * @return {@code True} if entry has been transitioned to state EVICTED.
   */
  boolean tryEvict(boolean updateSeq) {
    if (state.getReference() != RENTING || state.getStamp() != 0 || groupReserved()) return false;

    // Attempt to evict partition entries from cache.
    clearAll();

    if (map.isEmpty() && state.compareAndSet(RENTING, EVICTED, 0, 0)) {
      if (log.isDebugEnabled()) log.debug("Evicted partition: " + this);

      if (!GridQueryProcessor.isEnabled(cctx.config())) clearSwap();

      if (cctx.isDrEnabled()) cctx.dr().partitionEvicted(id);

      cctx.dataStructures().onPartitionEvicted(id);

      rent.onDone();

      ((GridDhtPreloader) cctx.preloader()).onPartitionEvicted(this, updateSeq);

      clearDeferredDeletes();

      return true;
    }

    return false;
  }
  /**
   * @param updateSeq Update sequence.
   * @return Future for evict attempt.
   */
  IgniteInternalFuture<Boolean> tryEvictAsync(boolean updateSeq) {
    if (map.isEmpty()
        && !GridQueryProcessor.isEnabled(cctx.config())
        && state.compareAndSet(RENTING, EVICTED, 0, 0)) {
      if (log.isDebugEnabled()) log.debug("Evicted partition: " + this);

      clearSwap();

      if (cctx.isDrEnabled()) cctx.dr().partitionEvicted(id);

      cctx.dataStructures().onPartitionEvicted(id);

      rent.onDone();

      ((GridDhtPreloader) cctx.preloader()).onPartitionEvicted(this, updateSeq);

      clearDeferredDeletes();

      return new GridFinishedFuture<>(true);
    }

    return cctx.closures()
        .callLocalSafe(
            new GPC<Boolean>() {
              @Override
              public Boolean call() {
                return tryEvict(true);
              }
            }, /*system pool*/
            true);
  }
    /**
     * @param fut Future.
     * @param doneCb Closure.
     */
    ChainFuture(
        GridFutureAdapter<R> fut, IgniteClosure<? super IgniteInternalFuture<R>, T> doneCb) {
      this.fut = fut;
      this.doneCb = doneCb;

      fut.listen(new GridFutureChainListener<>(this, doneCb));
    }
  /** {@inheritDoc} */
  @Override
  public boolean onDone(AffinityTopologyVersion res, Throwable err) {
    Map<Integer, Boolean> m = null;

    for (GridCacheContext cacheCtx : cctx.cacheContexts()) {
      if (cacheCtx.config().getTopologyValidator() != null && !CU.isSystemCache(cacheCtx.name())) {
        if (m == null) m = new HashMap<>();

        m.put(
            cacheCtx.cacheId(),
            cacheCtx.config().getTopologyValidator().validate(discoEvt.topologyNodes()));
      }
    }

    cacheValidRes = m != null ? m : Collections.<Integer, Boolean>emptyMap();

    cctx.cache().onExchangeDone(exchId.topologyVersion(), reqs, err);

    cctx.exchange().onExchangeDone(this, err);

    if (super.onDone(res, err) && !dummy && !forcePreload) {
      if (log.isDebugEnabled())
        log.debug(
            "Completed partition exchange [localNode="
                + cctx.localNodeId()
                + ", exchange= "
                + this
                + ']');

      initFut.onDone(err == null);

      GridTimeoutObject timeoutObj = this.timeoutObj;

      // Deschedule timeout object.
      if (timeoutObj != null) cctx.kernalContext().timeout().removeTimeoutObject(timeoutObj);

      if (exchId.isLeft()) {
        for (GridCacheContext cacheCtx : cctx.cacheContexts())
          cacheCtx.config().getAffinity().removeNode(exchId.nodeId());
      }

      return true;
    }

    return dummy;
  }
  /**
   * 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;
  }
  /** @param nodeId Left node id. */
  public void onNodeLeft(final UUID nodeId) {
    if (isDone()) return;

    if (!enterBusy()) return;

    try {
      // Wait for initialization part of this future to complete.
      initFut.listen(
          new CI1<IgniteInternalFuture<?>>() {
            @Override
            public void apply(IgniteInternalFuture<?> f) {
              if (isDone()) return;

              if (!enterBusy()) return;

              try {
                // Pretend to have received message from this node.
                rcvdIds.add(nodeId);

                Collection<UUID> rmtIds = GridDhtPartitionsExchangeFuture.this.rmtIds;

                assert rmtIds != null;

                ClusterNode oldest = oldestNode.get();

                if (oldest.id().equals(nodeId)) {
                  if (log.isDebugEnabled())
                    log.debug(
                        "Oldest node left or failed on partition exchange "
                            + "(will restart exchange process)) [oldestNodeId="
                            + oldest.id()
                            + ", exchangeId="
                            + exchId
                            + ']');

                  boolean set = false;

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

                  if (newOldest != null) {
                    // If local node is now oldest.
                    if (newOldest.id().equals(cctx.localNodeId())) {
                      synchronized (mux) {
                        if (oldestNode.compareAndSet(oldest, newOldest)) {
                          // If local node is just joining.
                          if (exchId.nodeId().equals(cctx.localNodeId())) {
                            try {
                              for (GridCacheContext cacheCtx : cctx.cacheContexts()) {
                                if (!cacheCtx.isLocal())
                                  cacheCtx
                                      .topology()
                                      .beforeExchange(GridDhtPartitionsExchangeFuture.this);
                              }
                            } catch (IgniteCheckedException e) {
                              onDone(e);

                              return;
                            }
                          }

                          set = true;
                        }
                      }
                    } else {
                      synchronized (mux) {
                        set = oldestNode.compareAndSet(oldest, newOldest);
                      }

                      if (set && log.isDebugEnabled())
                        log.debug(
                            "Reassigned oldest node [this="
                                + cctx.localNodeId()
                                + ", old="
                                + oldest.id()
                                + ", new="
                                + newOldest.id()
                                + ']');
                    }
                  }

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

                    for (Map.Entry<UUID, GridDhtPartitionsFullMessage> m : fullMsgs.entrySet())
                      onReceive(m.getKey(), m.getValue());

                    // Reassign oldest node and resend.
                    recheck();
                  }
                } else if (rmtIds.contains(nodeId)) {
                  if (log.isDebugEnabled())
                    log.debug(
                        "Remote node left of failed during partition exchange (will ignore) "
                            + "[rmtNode="
                            + nodeId
                            + ", exchangeId="
                            + exchId
                            + ']');

                  assert rmtNodes != null;

                  for (Iterator<ClusterNode> it = rmtNodes.iterator(); it.hasNext(); ) {
                    if (it.next().id().equals(nodeId)) it.remove();
                  }

                  if (allReceived() && ready.get() && replied.compareAndSet(false, true))
                    if (spreadPartitions()) onDone(exchId.topologyVersion());
                }
              } finally {
                leaveBusy();
              }
            }
          });
    } finally {
      leaveBusy();
    }
  }
  /**
   * @param nodeId Sender node ID.
   * @param msg Full partition info.
   */
  public void onReceive(final UUID nodeId, final GridDhtPartitionsFullMessage msg) {
    assert msg != null;

    if (isDone()) {
      if (log.isDebugEnabled())
        log.debug("Received message for finished future [msg=" + msg + ", fut=" + this + ']');

      return;
    }

    if (log.isDebugEnabled())
      log.debug("Received full partition map from node [nodeId=" + nodeId + ", msg=" + msg + ']');

    assert exchId.topologyVersion().equals(msg.topologyVersion());

    initFut.listen(
        new CI1<IgniteInternalFuture<Boolean>>() {
          @Override
          public void apply(IgniteInternalFuture<Boolean> t) {
            ClusterNode curOldest = oldestNode.get();

            if (!nodeId.equals(curOldest.id())) {
              if (log.isDebugEnabled())
                log.debug(
                    "Received full partition map from unexpected node [oldest="
                        + curOldest.id()
                        + ", unexpectedNodeId="
                        + nodeId
                        + ']');

              ClusterNode snd = cctx.discovery().node(nodeId);

              if (snd == null) {
                if (log.isDebugEnabled())
                  log.debug(
                      "Sender node left grid, will ignore message from unexpected node [nodeId="
                          + nodeId
                          + ", exchId="
                          + msg.exchangeId()
                          + ']');

                return;
              }

              // Will process message later if sender node becomes oldest node.
              if (snd.order() > curOldest.order()) fullMsgs.put(nodeId, msg);

              return;
            }

            assert msg.exchangeId().equals(exchId);

            assert msg.lastVersion() != null;

            cctx.versions().onReceived(nodeId, msg.lastVersion());

            updatePartitionFullMap(msg);

            onDone(exchId.topologyVersion());
          }
        });
  }
  /**
   * @param nodeId Sender node id.
   * @param msg Single partition info.
   */
  public void onReceive(final UUID nodeId, final GridDhtPartitionsSingleMessage msg) {
    assert msg != null;

    assert msg.exchangeId().equals(exchId);

    // Update last seen version.
    while (true) {
      GridCacheVersion old = lastVer.get();

      if (old == null || old.compareTo(msg.lastVersion()) < 0) {
        if (lastVer.compareAndSet(old, msg.lastVersion())) break;
      } else break;
    }

    if (isDone()) {
      if (log.isDebugEnabled())
        log.debug(
            "Received message for finished future (will reply only to sender) [msg="
                + msg
                + ", fut="
                + this
                + ']');

      sendAllPartitions(nodeId, cctx.gridConfig().getNetworkSendRetryCount());
    } else {
      initFut.listen(
          new CI1<IgniteInternalFuture<Boolean>>() {
            @Override
            public void apply(IgniteInternalFuture<Boolean> t) {
              try {
                if (!t.get()) // Just to check if there was an error.
                return;

                ClusterNode loc = cctx.localNode();

                singleMsgs.put(nodeId, msg);

                boolean match = true;

                // Check if oldest node has changed.
                if (!oldestNode.get().equals(loc)) {
                  match = false;

                  synchronized (mux) {
                    // Double check.
                    if (oldestNode.get().equals(loc)) match = true;
                  }
                }

                if (match) {
                  boolean allReceived;

                  synchronized (rcvdIds) {
                    if (rcvdIds.add(nodeId)) updatePartitionSingleMap(msg);

                    allReceived = allReceived();
                  }

                  // If got all replies, and initialization finished, and reply has not been sent
                  // yet.
                  if (allReceived && ready.get() && replied.compareAndSet(false, true)) {
                    spreadPartitions();

                    onDone(exchId.topologyVersion());
                  } else if (log.isDebugEnabled())
                    log.debug(
                        "Exchange future full map is not sent [allReceived="
                            + allReceived()
                            + ", ready="
                            + ready
                            + ", replied="
                            + replied.get()
                            + ", init="
                            + init.get()
                            + ", fut="
                            + this
                            + ']');
                }
              } catch (IgniteCheckedException e) {
                U.error(log, "Failed to initialize exchange future: " + this, e);
              }
            }
          });
    }
  }