/**
   * Creates new HTTP requests handler.
   *
   * @param hnd Handler.
   * @param authChecker Authentication checking closure.
   * @param log Logger.
   */
  GridJettyRestHandler(
      GridRestProtocolHandler hnd, GridClosure<String, Boolean> authChecker, GridLogger log) {
    assert hnd != null;
    assert log != null;

    this.hnd = hnd;
    this.log = log;
    this.authChecker = authChecker;

    // Init default page and favicon.
    try {
      initDefaultPage();

      if (log.isDebugEnabled()) log.debug("Initialized default page.");
    } catch (IOException e) {
      U.warn(log, "Failed to initialize default page: " + e.getMessage());
    }

    try {
      initFavicon();

      if (log.isDebugEnabled())
        log.debug(
            favicon != null ? "Initialized favicon, size: " + favicon.length : "Favicon is null.");
    } catch (IOException e) {
      U.warn(log, "Failed to initialize favicon: " + e.getMessage());
    }
  }
  /** {@inheritDoc} */
  @SuppressWarnings({"unchecked"})
  @Override
  public void listenAsync(@Nullable final GridInClosure<? super GridFuture<R>> lsnr) {
    if (lsnr != null) {
      checkValid();

      boolean done;

      synchronized (mux) {
        done = this.done;

        if (!done) lsnrs.add(lsnr);
      }

      if (done) {
        try {
          if (syncNotify) notifyListener(lsnr);
          else
            ctx.closure()
                .runLocalSafe(
                    new GPR() {
                      @Override
                      public void run() {
                        notifyListener(lsnr);
                      }
                    },
                    true);
        } catch (IllegalStateException ignore) {
          U.warn(
              null,
              "Future notification will not proceed because grid is stopped: " + ctx.gridName());
        }
      }
    }
  }
  /**
   * @param nodeId Sender node ID.
   * @param msg Finish transaction response.
   */
  private void processFinishResponse(UUID nodeId, GridDistributedTxFinishResponse<K, V> msg) {
    GridReplicatedTxCommitFuture<K, V> fut =
        (GridReplicatedTxCommitFuture<K, V>)
            ctx.mvcc().<GridCacheTx>future(msg.xid().id(), msg.futureId());

    if (fut != null) fut.onResult(nodeId);
    else U.warn(log, "Received finish response for unknown transaction: " + msg);
  }
Beispiel #4
0
  /**
   * @param nodeId Sender.
   * @param res Result.
   */
  void onResult(UUID nodeId, GridNearLockResponse<K, V> res) {
    if (!isDone()) {
      if (log.isDebugEnabled())
        log.debug(
            "Received lock response from node [nodeId="
                + nodeId
                + ", res="
                + res
                + ", fut="
                + this
                + ']');

      for (GridFuture<Boolean> fut : pending()) {
        if (isMini(fut)) {
          MiniFuture mini = (MiniFuture) fut;

          if (mini.futureId().equals(res.miniId())) {
            assert mini.node().id().equals(nodeId);

            if (log.isDebugEnabled())
              log.debug("Found mini future for response [mini=" + mini + ", res=" + res + ']');

            mini.onResult(res);

            if (log.isDebugEnabled())
              log.debug(
                  "Future after processed lock response [fut="
                      + this
                      + ", mini="
                      + mini
                      + ", res="
                      + res
                      + ']');

            return;
          }
        }
      }

      U.warn(
          log,
          "Failed to find mini future for response (perhaps due to stale message) [res="
              + res
              + ", fut="
              + this
              + ']');
    } else if (log.isDebugEnabled())
      log.debug(
          "Ignoring lock response from node (future is done) [nodeId="
              + nodeId
              + ", res="
              + res
              + ", fut="
              + this
              + ']');
  }
  /**
   * Adds new participant to deployment.
   *
   * @param dep Shared deployment.
   * @param meta Request metadata.
   * @return {@code True} if participant was added.
   */
  private boolean addParticipant(SharedDeployment dep, GridDeploymentMetadata meta) {
    assert dep != null;
    assert meta != null;

    assert Thread.holdsLock(mux);

    if (!checkModeMatch(dep, meta)) return false;

    if (meta.participants() != null) {
      for (Map.Entry<UUID, GridTuple2<GridUuid, Long>> e : meta.participants().entrySet()) {
        dep.addParticipant(e.getKey(), e.getValue().get1(), e.getValue().get2());

        if (log.isDebugEnabled())
          log.debug(
              "Added new participant [nodeId="
                  + e.getKey()
                  + ", clsLdrId="
                  + e.getValue().get1()
                  + ", seqNum="
                  + e.getValue().get2()
                  + ']');
      }
    }

    if (dep.deployMode() == CONTINUOUS || meta.participants() == null) {
      if (!dep.addParticipant(meta.senderNodeId(), meta.classLoaderId(), meta.sequenceNumber())) {
        U.warn(
            log,
            "Failed to create shared mode deployment "
                + "(requested class loader was already undeployed, did sender node leave grid?) "
                + "[clsLdrId="
                + meta.classLoaderId()
                + ", senderNodeId="
                + meta.senderNodeId()
                + ']');

        return false;
      }

      if (log.isDebugEnabled())
        log.debug(
            "Added new participant [nodeId="
                + meta.senderNodeId()
                + ", clsLdrId="
                + meta.classLoaderId()
                + ", seqNum="
                + meta.sequenceNumber()
                + ']');
    }

    return true;
  }
  /** {@inheritDoc} */
  @Override
  public void onDiscoveryDataReceived(UUID nodeId, UUID rmtNodeId, Serializable data) {
    Map<String, Serializable> discData = (Map<String, Serializable>) data;

    if (discData != null) {
      for (Map.Entry<String, Serializable> e : discData.entrySet()) {
        PluginProvider provider = plugins.get(e.getKey());

        if (provider != null) provider.receiveDiscoveryData(nodeId, e.getValue());
        else U.warn(log, "Received discovery data for unknown plugin: " + e.getKey());
      }
    }
  }
  /**
   * Processes lock response.
   *
   * @param nodeId Sender node ID.
   * @param res Lock response.
   */
  private void processLockResponse(UUID nodeId, GridDistributedLockResponse<K, V> res) {
    GridReplicatedLockFuture<K, V> fut = futurex(res.lockId(), res.futureId());

    if (fut == null) {
      U.warn(log, "Received lock response for non-existing future (will ignore): " + res);
    } else {
      fut.onResult(nodeId, res);

      if (fut.isDone()) {
        ctx.mvcc().removeFuture(fut);

        if (log.isDebugEnabled())
          log.debug("Received all replies for future (future was removed): " + fut);
      }
    }
  }
  /**
   * Checks if deployment modes match.
   *
   * @param dep Shared deployment.
   * @param meta Request metadata.
   * @return {@code True} if shared deployment modes match.
   */
  private boolean checkModeMatch(GridDeploymentInfo dep, GridDeploymentMetadata meta) {
    if (dep.deployMode() != meta.deploymentMode()) {
      U.warn(
          log,
          "Received invalid deployment mode (will not deploy, make sure that all nodes "
              + "executing the same classes in shared mode have identical GridDeploymentMode parameter) [mode="
              + meta.deploymentMode()
              + ", expected="
              + dep.deployMode()
              + ']');

      return false;
    }

    return true;
  }
Beispiel #9
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    /** @param e Error. */
    void onResult(Throwable e) {
      if (rcvRes.compareAndSet(false, true)) {
        if (log.isDebugEnabled())
          log.debug("Failed to get future result [fut=" + this + ", err=" + e + ']');

        // Fail.
        onDone(e);
      } else
        U.warn(
            log,
            "Received error after another result has been processed [fut="
                + GridNearLockFuture.this
                + ", mini="
                + this
                + ']',
            e);
    }
  /** {@inheritDoc} */
  @SuppressWarnings("deprecation")
  @Override
  public void start() throws IgniteException {
    if (sesFactory == null && F.isEmpty(hibernateCfgPath))
      throw new IgniteException(
          "Either session factory or Hibernate configuration file is required by "
              + getClass().getSimpleName()
              + '.');

    if (!F.isEmpty(hibernateCfgPath)) {
      if (sesFactory == null) {
        try {
          URL url = new URL(hibernateCfgPath);

          sesFactory = new Configuration().configure(url).buildSessionFactory();
        } catch (MalformedURLException ignored) {
          // No-op.
        }

        if (sesFactory == null) {
          File cfgFile = new File(hibernateCfgPath);

          if (cfgFile.exists())
            sesFactory = new Configuration().configure(cfgFile).buildSessionFactory();
        }

        if (sesFactory == null)
          sesFactory = new Configuration().configure(hibernateCfgPath).buildSessionFactory();

        if (sesFactory == null)
          throw new IgniteException(
              "Failed to resolve Hibernate configuration file: " + hibernateCfgPath);

        closeSesOnStop = true;
      } else
        U.warn(
            log,
            "Hibernate configuration file configured in "
                + getClass().getSimpleName()
                + " will be ignored (session factory is already set).");
    }
  }
  /** {@inheritDoc} */
  @Override
  public void close() {
    closed = true;

    U.closeQuiet(srvSock);

    if (gcWorker != null) {
      U.cancel(gcWorker);

      // This method may be called from already interrupted thread.
      // Need to ensure cleaning on close.
      boolean interrupted = Thread.interrupted();

      try {
        U.join(gcWorker);
      } catch (IgniteInterruptedCheckedException e) {
        U.warn(log, "Interrupted when stopping GC worker.", e);
      } finally {
        if (interrupted) Thread.currentThread().interrupt();
      }
    }
  }
  /**
   * Notifies single listener.
   *
   * @param lsnr Listener.
   */
  private void notifyListener(GridInClosure<? super GridFuture<R>> lsnr) {
    assert lsnr != null;

    try {
      lsnr.apply(this);
    } catch (IllegalStateException ignore) {
      U.warn(
          null,
          "Failed to notify listener (grid is stopped) [grid="
              + ctx.gridName()
              + ", lsnr="
              + lsnr
              + ']');
    } catch (RuntimeException e) {
      U.error(log, "Failed to notify listener: " + lsnr, e);

      throw e;
    } catch (Error e) {
      U.error(log, "Failed to notify listener: " + lsnr, e);

      throw e;
    }
  }
  /**
   * Processes lock request.
   *
   * @param nodeId Sender node ID.
   * @param msg Lock request.
   */
  @SuppressWarnings({"unchecked", "ThrowableInstanceNeverThrown"})
  private void processLockRequest(UUID nodeId, GridDistributedLockRequest<K, V> msg) {
    assert !nodeId.equals(locNodeId);

    List<byte[]> keys = msg.keyBytes();

    int cnt = keys.size();

    GridReplicatedTxRemote<K, V> tx = null;

    GridDistributedLockResponse res;

    ClassLoader ldr = null;

    try {
      ldr = ctx.deploy().globalLoader();

      if (ldr != null) {
        res = new GridDistributedLockResponse(msg.version(), msg.futureId(), cnt);

        for (int i = 0; i < keys.size(); i++) {
          byte[] bytes = keys.get(i);
          K key = msg.keys().get(i);

          Collection<GridCacheMvccCandidate<K>> cands = msg.candidatesByIndex(i);

          if (bytes == null) continue;

          if (log.isDebugEnabled()) log.debug("Unmarshalled key: " + key);

          GridDistributedCacheEntry<K, V> entry = null;

          while (true) {
            try {
              entry = entryexx(key);

              // Handle implicit locks for pessimistic transactions.
              if (msg.inTx()) {
                tx = ctx.tm().tx(msg.version());

                if (tx != null) {
                  if (msg.txRead()) tx.addRead(key, bytes);
                  else tx.addWrite(key, bytes);
                } else {
                  tx =
                      new GridReplicatedTxRemote<K, V>(
                          nodeId,
                          msg.threadId(),
                          msg.version(),
                          null,
                          PESSIMISTIC,
                          msg.isolation(),
                          msg.isInvalidate(),
                          msg.timeout(),
                          key,
                          bytes,
                          msg.txRead(),
                          ctx);

                  tx = ctx.tm().onCreated(tx);

                  if (tx == null || !ctx.tm().onStarted(tx))
                    throw new GridCacheTxRollbackException(
                        "Failed to acquire lock "
                            + "(transaction has been completed): "
                            + msg.version());
                }
              }

              // Add remote candidate before reordering.
              entry.addRemote(
                  msg.nodeId(),
                  null,
                  msg.threadId(),
                  msg.version(),
                  msg.timeout(),
                  tx != null && tx.ec(),
                  tx != null,
                  tx != null && tx.implicitSingle());

              // Remote candidates for ordered lock queuing.
              entry.addRemoteCandidates(
                  cands, msg.version(), msg.committedVersions(), msg.rolledbackVersions());

              // Double-check in case if sender node left the grid.
              if (ctx.discovery().node(msg.nodeId()) == null) {
                if (log.isDebugEnabled())
                  log.debug(
                      "Node requesting lock left grid (lock request will be ignored): " + msg);

                if (tx != null) tx.rollback();

                return;
              }

              res.setCandidates(
                  i,
                  entry.localCandidates(),
                  ctx.tm().committedVersions(msg.version()),
                  ctx.tm().rolledbackVersions(msg.version()));

              res.addValueBytes(
                  entry.rawGet(), msg.returnValue(i) ? entry.valueBytes(null) : null, ctx);

              // Entry is legit.
              break;
            } catch (GridCacheEntryRemovedException ignored) {
              assert entry.obsoleteVersion() != null
                  : "Obsolete flag not set on removed entry: " + entry;

              if (log.isDebugEnabled())
                log.debug(
                    "Received entry removed exception (will retry on renewed entry): " + entry);

              if (tx != null) {
                tx.clearEntry(entry.key());

                if (log.isDebugEnabled())
                  log.debug(
                      "Cleared removed entry from remote transaction (will retry) [entry="
                          + entry
                          + ", tx="
                          + tx
                          + ']');
              }
            }
          }
        }
      } else {
        String err = "Failed to acquire deployment class for message: " + msg;

        U.warn(log, err);

        res =
            new GridDistributedLockResponse(msg.version(), msg.futureId(), new GridException(err));
      }
    } catch (GridCacheTxRollbackException e) {
      if (log.isDebugEnabled())
        log.debug("Received lock request for completed transaction (will ignore): " + e);

      res = new GridDistributedLockResponse(msg.version(), msg.futureId(), e);
    } catch (GridException e) {
      String err = "Failed to unmarshal at least one of the keys for lock request message: " + msg;

      log.error(err, e);

      res =
          new GridDistributedLockResponse(msg.version(), msg.futureId(), new GridException(err, e));

      if (tx != null) tx.rollback();
    } catch (GridDistributedLockCancelledException ignored) {
      // Received lock request for cancelled lock.
      if (log.isDebugEnabled())
        log.debug("Received lock request for canceled lock (will ignore): " + msg);

      if (tx != null) tx.rollback();

      // Don't send response back.
      return;
    }

    GridNode node = ctx.discovery().node(msg.nodeId());

    boolean releaseAll = false;

    if (node != null) {
      try {
        // Reply back to sender.
        ctx.io().send(node, res);
      } catch (GridException e) {
        U.error(log, "Failed to send message to node (did the node leave grid?): " + node.id(), e);

        releaseAll = ldr != null;
      }
    }
    // If sender left grid, release all locks acquired so far.
    else releaseAll = ldr != null;

    // Release all locks because sender node left grid.
    if (releaseAll) {
      for (K key : msg.keys()) {
        while (true) {
          GridDistributedCacheEntry<K, V> entry = peekexx(key);

          try {
            if (entry != null) entry.removeExplicitNodeLocks(msg.nodeId());

            break;
          } catch (GridCacheEntryRemovedException ignore) {
            if (log.isDebugEnabled())
              log.debug(
                  "Attempted to remove lock on removed entity during failure "
                      + "of replicated lock request handling (will retry): "
                      + entry);
          }
        }
      }

      U.warn(
          log, "Sender node left grid in the midst of lock acquisition (locks will be released).");
    }
  }
Beispiel #14
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  /** {@inheritDoc} */
  @SuppressWarnings({"CatchGenericClass", "ThrowableInstanceNeverThrown"})
  @Override
  public void finish(boolean commit) throws GridException {
    if (log.isDebugEnabled())
      log.debug("Finishing near local tx [tx=" + this + ", commit=" + commit + "]");

    if (commit) {
      if (!state(COMMITTING)) {
        GridCacheTxState state = state();

        if (state != COMMITTING && state != COMMITTED)
          throw new GridException(
              "Invalid transaction state for commit [state=" + state() + ", tx=" + this + ']');
        else {
          if (log.isDebugEnabled())
            log.debug(
                "Invalid transaction state for commit (another thread is committing): " + this);

          return;
        }
      }
    } else {
      if (!state(ROLLING_BACK)) {
        if (log.isDebugEnabled())
          log.debug(
              "Invalid transaction state for rollback [state=" + state() + ", tx=" + this + ']');

        return;
      }
    }

    GridException err = null;

    // Commit to DB first. This way if there is a failure, transaction
    // won't be committed.
    try {
      if (commit && !isRollbackOnly()) userCommit();
      else userRollback();
    } catch (GridException e) {
      err = e;

      commit = false;

      // If heuristic error.
      if (!isRollbackOnly()) {
        invalidate = true;

        U.warn(
            log,
            "Set transaction invalidation flag to true due to error [tx="
                + this
                + ", err="
                + err
                + ']');
      }
    }

    if (err != null) {
      state(UNKNOWN);

      throw err;
    } else {
      if (!state(commit ? COMMITTED : ROLLED_BACK)) {
        state(UNKNOWN);

        throw new GridException("Invalid transaction state for commit or rollback: " + this);
      }
    }
  }
  /**
   * Initializes store.
   *
   * @throws GridException If failed to initialize.
   */
  private void init() throws GridException {
    if (initGuard.compareAndSet(false, true)) {
      if (log.isDebugEnabled()) log.debug("Initializing cache store.");

      try {
        if (sesFactory != null)
          // Session factory has been provided - nothing to do.
          return;

        if (!F.isEmpty(hibernateCfgPath)) {
          try {
            URL url = new URL(hibernateCfgPath);

            sesFactory = new Configuration().configure(url).buildSessionFactory();

            if (log.isDebugEnabled()) log.debug("Configured session factory using URL: " + url);

            // Session factory has been successfully initialized.
            return;
          } catch (MalformedURLException e) {
            if (log.isDebugEnabled())
              log.debug("Caught malformed URL exception: " + e.getMessage());
          }

          // Provided path is not a valid URL. File?
          File cfgFile = new File(hibernateCfgPath);

          if (cfgFile.exists()) {
            sesFactory = new Configuration().configure(cfgFile).buildSessionFactory();

            if (log.isDebugEnabled())
              log.debug("Configured session factory using file: " + hibernateCfgPath);

            // Session factory has been successfully initialized.
            return;
          }

          // Provided path is not a file. Classpath resource?
          sesFactory = new Configuration().configure(hibernateCfgPath).buildSessionFactory();

          if (log.isDebugEnabled())
            log.debug("Configured session factory using classpath resource: " + hibernateCfgPath);
        } else {
          if (hibernateProps == null) {
            U.warn(
                log, "No Hibernate configuration has been provided for store (will use default).");

            hibernateProps = new Properties();

            hibernateProps.setProperty("hibernate.connection.url", DFLT_CONN_URL);
            hibernateProps.setProperty("hibernate.show_sql", DFLT_SHOW_SQL);
            hibernateProps.setProperty("hibernate.hbm2ddl.auto", DFLT_HBM2DDL_AUTO);
          }

          Configuration cfg = new Configuration();

          cfg.setProperties(hibernateProps);

          assert resourceAvailable(MAPPING_RESOURCE);

          cfg.addResource(MAPPING_RESOURCE);

          sesFactory = cfg.buildSessionFactory();

          if (log.isDebugEnabled())
            log.debug("Configured session factory using properties: " + hibernateProps);
        }
      } catch (HibernateException e) {
        throw new GridException("Failed to initialize store.", e);
      } finally {
        initLatch.countDown();
      }
    } else if (initLatch.getCount() > 0) U.await(initLatch);

    if (sesFactory == null) throw new GridException("Cache store was not properly initialized.");
  }
  /**
   * Removes obsolete deployments in case of redeploy.
   *
   * @param meta Request metadata.
   * @return List of shares deployment.
   */
  private GridTuple2<Boolean, SharedDeployment> checkRedeploy(GridDeploymentMetadata meta) {
    assert Thread.holdsLock(mux);

    SharedDeployment newDep = null;

    for (List<SharedDeployment> deps : cache.values()) {
      for (SharedDeployment dep : deps) {
        if (!dep.isUndeployed() && !dep.isPendingUndeploy()) {
          long undeployTimeout = ctx.config().getNetworkTimeout();

          SharedDeployment doomed = null;

          // Only check deployments with no participants.
          if (!dep.hasParticipants()) {
            // In case of SHARED deployment it is possible to get hear if
            // unmarshalling happens during undeploy. In this case, we
            // simply don't do anything.
            if (dep.deployMode() == CONTINUOUS) {
              if (dep.existingDeployedClass(meta.className()) != null) {
                // Change from shared deploy to shared undeploy or user version change.
                // Simply remove all deployments with no participating nodes.
                if (meta.deploymentMode() == SHARED
                    || !meta.userVersion().equals(dep.userVersion())) doomed = dep;
              }
            }
          }
          // If there are participants, we undeploy if class loader ID on some node changed.
          else if (dep.existingDeployedClass(meta.className()) != null) {
            GridTuple2<GridUuid, Long> ldr = dep.getClassLoaderId(meta.senderNodeId());

            if (ldr != null) {
              if (!ldr.get1().equals(meta.classLoaderId())) {
                // If deployed sequence number is less, then schedule for undeployment.
                if (ldr.get2() < meta.sequenceNumber()) {
                  if (log.isDebugEnabled())
                    log.debug(
                        "Received request for a class with newer sequence number "
                            + "(will schedule current class for undeployment) [newSeq="
                            + meta.sequenceNumber()
                            + ", oldSeq="
                            + ldr.get2()
                            + ", senderNodeId="
                            + meta.senderNodeId()
                            + ", newClsLdrId="
                            + meta.classLoaderId()
                            + ", oldClsLdrId="
                            + ldr.get1()
                            + ']');

                  doomed = dep;
                } else if (ldr.get2() > meta.sequenceNumber()) {
                  long time = System.currentTimeMillis() - dep.timestamp();

                  if (newDep == null && time < ctx.config().getNetworkTimeout()) {
                    // Set undeployTimeout, so the class will be scheduled
                    // for undeployment.
                    undeployTimeout = ctx.config().getNetworkTimeout() - time;

                    if (log.isDebugEnabled())
                      log.debug(
                          "Received execution request for a stale class (will deploy and "
                              + "schedule undeployment in "
                              + undeployTimeout
                              + "ms) "
                              + "[curSeq="
                              + ldr.get2()
                              + ", staleSeq="
                              + meta.sequenceNumber()
                              + ", cls="
                              + meta.className()
                              + ", senderNodeId="
                              + meta.senderNodeId()
                              + ", curLdrId="
                              + ldr.get1()
                              + ", staleLdrId="
                              + meta.classLoaderId()
                              + ']');

                    // We got the redeployed class before the old one.
                    // Simply create a temporary deployment for the sender node,
                    // and schedule undeploy for it.
                    newDep = createNewDeployment(meta, false);

                    doomed = newDep;
                  } else {
                    U.warn(
                        log,
                        "Received execution request for a class that has been redeployed "
                            + "(will ignore): "
                            + meta.alias());

                    if (log.isDebugEnabled())
                      log.debug(
                          "Received execution request for a class that has been redeployed "
                              + "(will ignore) [alias="
                              + meta.alias()
                              + ", dep="
                              + dep
                              + ']');

                    return F.t(false, null);
                  }
                } else {
                  U.error(
                      log,
                      "Sequence number does not correspond to class loader ID [seqNum="
                          + meta.sequenceNumber()
                          + ", dep="
                          + dep
                          + ']');

                  return F.t(false, null);
                }
              }
            }
          }

          if (doomed != null) {
            doomed.onUndeployScheduled();

            if (log.isDebugEnabled()) log.debug("Deployment was scheduled for undeploy: " + doomed);

            // Lifespan time.
            final long endTime = System.currentTimeMillis() + undeployTimeout;

            // Deployment to undeploy.
            final SharedDeployment undep = doomed;

            ctx.timeout()
                .addTimeoutObject(
                    new GridTimeoutObject() {
                      @Override
                      public GridUuid timeoutId() {
                        return undep.classLoaderId();
                      }

                      @Override
                      public long endTime() {
                        return endTime < 0 ? Long.MAX_VALUE : endTime;
                      }

                      @Override
                      public void onTimeout() {
                        boolean removed = false;

                        // Hot redeployment.
                        synchronized (mux) {
                          assert undep.isPendingUndeploy();

                          if (!undep.isUndeployed()) {
                            undep.undeploy();

                            undep.onRemoved();

                            removed = true;

                            Collection<SharedDeployment> deps = cache.get(undep.userVersion());

                            if (deps != null) {
                              for (Iterator<SharedDeployment> i = deps.iterator(); i.hasNext(); )
                                if (i.next() == undep) i.remove();

                              if (deps.isEmpty()) cache.remove(undep.userVersion());
                            }

                            if (log.isInfoEnabled())
                              log.info(
                                  "Undeployed class loader due to deployment mode change, "
                                      + "user version change, or hot redeployment: "
                                      + undep);
                          }
                        }

                        // Outside synchronization.
                        if (removed) undep.recordUndeployed(null);
                      }
                    });
          }
        }
      }
    }

    if (newDep != null) {
      List<SharedDeployment> list =
          F.addIfAbsent(cache, meta.userVersion(), F.<SharedDeployment>newList());

      assert list != null;

      list.add(newDep);
    }

    return F.t(true, newDep);
  }
  /**
   * @param nodeId Primary node ID.
   * @param req Request.
   * @return Remote transaction.
   * @throws GridException If failed.
   * @throws GridDistributedLockCancelledException If lock has been cancelled.
   */
  @SuppressWarnings({"RedundantTypeArguments"})
  @Nullable
  public GridNearTxRemote<K, V> startRemoteTx(UUID nodeId, GridDhtLockRequest<K, V> req)
      throws GridException, GridDistributedLockCancelledException {
    List<byte[]> nearKeyBytes = req.nearKeyBytes();

    GridNearTxRemote<K, V> tx = null;

    ClassLoader ldr = ctx.deploy().globalLoader();

    if (ldr != null) {
      for (int i = 0; i < nearKeyBytes.size(); i++) {
        byte[] bytes = nearKeyBytes.get(i);

        if (bytes == null) continue;

        K key = req.nearKeys().get(i);

        Collection<GridCacheMvccCandidate<K>> cands = req.candidatesByIndex(i);

        if (log.isDebugEnabled()) log.debug("Unmarshalled key: " + key);

        GridNearCacheEntry<K, V> entry = null;

        while (true) {
          try {
            entry = peekExx(key);

            if (entry != null) {
              entry.keyBytes(bytes);

              // Handle implicit locks for pessimistic transactions.
              if (req.inTx()) {
                tx = ctx.tm().tx(req.version());

                if (tx != null) tx.addWrite(key, bytes, null /*Value.*/, null /*Value bytes.*/);
                else {
                  tx =
                      new GridNearTxRemote<K, V>(
                          nodeId,
                          req.nearNodeId(),
                          req.threadId(),
                          req.version(),
                          null,
                          PESSIMISTIC,
                          req.isolation(),
                          req.isInvalidate(),
                          req.timeout(),
                          key,
                          bytes,
                          null, // Value.
                          null, // Value bytes.
                          ctx);

                  if (tx.empty()) return tx;

                  tx = ctx.tm().onCreated(tx);

                  if (tx == null || !ctx.tm().onStarted(tx))
                    throw new GridCacheTxRollbackException(
                        "Failed to acquire lock "
                            + "(transaction has been completed): "
                            + req.version());
                }
              }

              // Add remote candidate before reordering.
              entry.addRemote(
                  req.nodeId(),
                  nodeId,
                  req.threadId(),
                  req.version(),
                  req.timeout(),
                  tx != null && tx.ec(),
                  tx != null,
                  tx != null && tx.implicitSingle());

              // Remote candidates for ordered lock queuing.
              entry.addRemoteCandidates(
                  cands, req.version(), req.committedVersions(), req.rolledbackVersions());

              entry.orderOwned(req.version(), req.owned(entry.key()));
            }

            // Double-check in case if sender node left the grid.
            if (ctx.discovery().node(req.nodeId()) == null) {
              if (log.isDebugEnabled())
                log.debug("Node requesting lock left grid (lock request will be ignored): " + req);

              if (tx != null) tx.rollback();

              return null;
            }

            // Entry is legit.
            break;
          } catch (GridCacheEntryRemovedException ignored) {
            assert entry.obsoleteVersion() != null
                : "Obsolete flag not set on removed entry: " + entry;

            if (log.isDebugEnabled())
              log.debug("Received entry removed exception (will retry on renewed entry): " + entry);

            if (tx != null) {
              tx.clearEntry(entry.key());

              if (log.isDebugEnabled())
                log.debug(
                    "Cleared removed entry from remote transaction (will retry) [entry="
                        + entry
                        + ", tx="
                        + tx
                        + ']');
            }
          }
        }
      }
    } else {
      String err = "Failed to acquire deployment class loader for message: " + req;

      U.warn(log, err);

      throw new GridException(err);
    }

    return tx;
  }
  /**
   * @param nodeId Primary node ID.
   * @param req Request.
   * @return Remote transaction.
   * @throws GridException If failed.
   * @throws GridDistributedLockCancelledException If lock has been cancelled.
   */
  @SuppressWarnings({"RedundantTypeArguments"})
  @Nullable
  public GridNearTxRemote<K, V> startRemoteTxForFinish(
      UUID nodeId, GridDhtTxFinishRequest<K, V> req)
      throws GridException, GridDistributedLockCancelledException {
    GridNearTxRemote<K, V> tx = null;

    ClassLoader ldr = ctx.deploy().globalLoader();

    if (ldr != null) {
      for (GridCacheTxEntry<K, V> txEntry : req.nearWrites()) {
        GridDistributedCacheEntry<K, V> entry = null;

        while (true) {
          try {
            entry = peekExx(txEntry.key());

            if (entry != null) {
              entry.keyBytes(txEntry.keyBytes());

              // Handle implicit locks for pessimistic transactions.
              tx = ctx.tm().tx(req.version());

              if (tx != null) {
                if (tx.local()) return null;

                if (tx.markFinalizing()) tx.addWrite(txEntry.key(), txEntry.keyBytes());
                else return null;
              } else {
                tx =
                    new GridNearTxRemote<K, V>(
                        nodeId,
                        req.nearNodeId(),
                        req.threadId(),
                        req.version(),
                        null,
                        PESSIMISTIC,
                        req.isolation(),
                        req.isInvalidate(),
                        0,
                        txEntry.key(),
                        txEntry.keyBytes(),
                        txEntry.value(),
                        txEntry.valueBytes(),
                        ctx);

                if (tx.empty()) return tx;

                tx = ctx.tm().onCreated(tx);

                if (tx == null || !ctx.tm().onStarted(tx))
                  throw new GridCacheTxRollbackException(
                      "Failed to acquire lock "
                          + "(transaction has been completed): "
                          + req.version());

                if (!tx.markFinalizing()) return null;
              }

              // Add remote candidate before reordering.
              if (txEntry.explicitVersion() == null)
                entry.addRemote(
                    req.nearNodeId(),
                    nodeId,
                    req.threadId(),
                    req.version(),
                    0,
                    tx.ec(),
                    /*tx*/ true,
                    tx.implicitSingle());

              // Remote candidates for ordered lock queuing.
              entry.addRemoteCandidates(
                  Collections.<GridCacheMvccCandidate<K>>emptyList(),
                  req.version(),
                  req.committedVersions(),
                  req.rolledbackVersions());
            }

            // Double-check in case if sender node left the grid.
            if (ctx.discovery().node(req.nearNodeId()) == null) {
              if (log.isDebugEnabled())
                log.debug("Node requesting lock left grid (lock request will be ignored): " + req);

              if (tx != null) tx.rollback();

              return null;
            }

            // Entry is legit.
            break;
          } catch (GridCacheEntryRemovedException ignored) {
            assert entry.obsoleteVersion() != null
                : "Obsolete flag not set on removed entry: " + entry;

            if (log.isDebugEnabled())
              log.debug("Received entry removed exception (will retry on renewed entry): " + entry);

            if (tx != null) {
              tx.clearEntry(entry.key());

              if (log.isDebugEnabled())
                log.debug(
                    "Cleared removed entry from remote transaction (will retry) [entry="
                        + entry
                        + ", tx="
                        + tx
                        + ']');
            }
          }
        }
      }
    } else {
      String err = "Failed to acquire deployment class loader for message: " + req;

      U.warn(log, err);

      throw new GridException(err);
    }

    return tx;
  }
    /**
     * @param entries Entries to submit.
     * @param curFut Current future.
     * @throws GridInterruptedException If interrupted.
     */
    private void submit(final List<Map.Entry<K, V>> entries, final GridFutureAdapter<Object> curFut)
        throws GridInterruptedException {
      assert entries != null;
      assert !entries.isEmpty();
      assert curFut != null;

      incrementActiveTasks();

      GridFuture<Object> fut;
      if (isLocNode) {
        fut =
            ctx.closure()
                .callLocalSafe(
                    new GridDataLoadUpdateJob<>(ctx, log, cacheName, entries, false, updater),
                    false);

        locFuts.add(fut);

        fut.listenAsync(
            new GridInClosure<GridFuture<Object>>() {
              @Override
              public void apply(GridFuture<Object> t) {
                try {
                  boolean rmv = locFuts.remove(t);

                  assert rmv;

                  curFut.onDone(t.get());
                } catch (GridException e) {
                  curFut.onDone(e);
                }
              }
            });
      } else {
        byte[] entriesBytes;

        try {
          entriesBytes = ctx.config().getMarshaller().marshal(entries);

          if (updaterBytes == null) {
            assert updater != null;

            updaterBytes = ctx.config().getMarshaller().marshal(updater);
          }

          if (topicBytes == null) topicBytes = ctx.config().getMarshaller().marshal(topic);
        } catch (GridException e) {
          U.error(log, "Failed to marshal (request will not be sent).", e);

          return;
        }

        GridDeployment dep = null;
        GridPeerDeployAware jobPda0 = null;

        if (ctx.deploy().enabled()) {
          try {
            jobPda0 = jobPda;

            assert jobPda0 != null;

            dep = ctx.deploy().deploy(jobPda0.deployClass(), jobPda0.classLoader());
          } catch (GridException e) {
            U.error(
                log,
                "Failed to deploy class (request will not be sent): " + jobPda0.deployClass(),
                e);

            return;
          }

          if (dep == null)
            U.warn(log, "Failed to deploy class (request will be sent): " + jobPda0.deployClass());
        }

        long reqId = idGen.incrementAndGet();

        fut = curFut;

        reqs.put(reqId, (GridFutureAdapter<Object>) fut);

        GridDataLoadRequest<Object, Object> req =
            new GridDataLoadRequest<>(
                reqId,
                topicBytes,
                cacheName,
                updaterBytes,
                entriesBytes,
                true,
                dep != null ? dep.deployMode() : null,
                dep != null ? jobPda0.deployClass().getName() : null,
                dep != null ? dep.userVersion() : null,
                dep != null ? dep.participants() : null,
                dep != null ? dep.classLoaderId() : null,
                dep == null);

        try {
          ctx.io().send(node, TOPIC_DATALOAD, req, PUBLIC_POOL);

          if (log.isDebugEnabled())
            log.debug("Sent request to node [nodeId=" + node.id() + ", req=" + req + ']');
        } catch (GridException e) {
          if (ctx.discovery().alive(node) && ctx.discovery().pingNode(node.id()))
            ((GridFutureAdapter<Object>) fut).onDone(e);
          else
            ((GridFutureAdapter<Object>) fut)
                .onDone(
                    new GridTopologyException(
                        "Failed to send " + "request (node has left): " + node.id()));
        }
      }
    }
  /** {@inheritDoc} */
  @SuppressWarnings("BusyWait")
  @Override
  public void start(final GridRestProtocolHandler hnd) throws GridException {
    assert hnd != null;

    GridConfiguration cfg = ctx.config();

    GridNioServerListener<GridClientMessage> lsnr = new GridTcpRestNioListener(log, hnd);

    GridNioParser parser = new GridTcpRestParser(log);

    try {
      host = resolveRestTcpHost(cfg);

      SSLContext sslCtx = null;

      if (cfg.isRestTcpSslEnabled()) {
        GridSslContextFactory factory = cfg.getRestTcpSslContextFactory();

        if (factory == null)
          // Thrown SSL exception instead of GridException for writing correct warning message into
          // log.
          throw new SSLException("SSL is enabled, but SSL context factory is not specified.");

        sslCtx = factory.createSslContext();
      }

      int lastPort = cfg.getRestTcpPort() + cfg.getRestPortRange() - 1;

      for (port = cfg.getRestTcpPort(); port <= lastPort; port++) {
        if (startTcpServer(host, port, lsnr, parser, sslCtx, cfg)) {
          if (log.isInfoEnabled()) log.info(startInfo());

          return;
        }
      }

      U.warn(
          log,
          "Failed to start TCP binary REST server (possibly all ports in range are in use) "
              + "[firstPort="
              + cfg.getRestTcpPort()
              + ", lastPort="
              + lastPort
              + ", host="
              + host
              + ']');
    } catch (SSLException e) {
      U.warn(
          log,
          "Failed to start " + name() + " protocol on port " + port + ": " + e.getMessage(),
          "Failed to start "
              + name()
              + " protocol on port "
              + port
              + ". Check if SSL context factory is "
              + "properly configured.");
    } catch (IOException e) {
      U.warn(
          log,
          "Failed to start " + name() + " protocol on port " + port + ": " + e.getMessage(),
          "Failed to start "
              + name()
              + " protocol on port "
              + port
              + ". "
              + "Check restTcpHost configuration property.");
    }
  }
  /**
   * @param nodeId Sender node ID.
   * @param req Finish transaction message.
   */
  @SuppressWarnings({"CatchGenericClass"})
  private void processFinishRequest(UUID nodeId, GridDistributedTxFinishRequest<K, V> req) {
    assert nodeId != null;
    assert req != null;

    GridReplicatedTxRemote<K, V> tx = ctx.tm().tx(req.version());

    try {
      ClassLoader ldr = ctx.deploy().globalLoader();

      if (req.commit()) {
        // If lock was acquired explicitly.
        if (tx == null) {
          // Create transaction and add entries.
          tx =
              ctx.tm()
                  .onCreated(
                      new GridReplicatedTxRemote<K, V>(
                          ldr,
                          nodeId,
                          req.threadId(),
                          req.version(),
                          req.commitVersion(),
                          PESSIMISTIC,
                          READ_COMMITTED,
                          req.isInvalidate(),
                          /*timeout */ 0,
                          /*read entries*/ null,
                          req.writes(),
                          ctx));

          if (tx == null || !ctx.tm().onStarted(tx))
            throw new GridCacheTxRollbackException(
                "Attempt to start a completed " + "transaction: " + req);
        } else {
          boolean set = tx.commitVersion(req.commitVersion());

          assert set;
        }

        Collection<GridCacheTxEntry<K, V>> writeEntries = req.writes();

        if (!F.isEmpty(writeEntries)) {
          // In OPTIMISTIC mode, we get the values at PREPARE stage.
          assert tx.concurrency() == PESSIMISTIC;

          for (GridCacheTxEntry<K, V> entry : writeEntries) {
            // Unmarshal write entries.
            entry.unmarshal(ctx, ldr);

            if (log.isDebugEnabled())
              log.debug(
                  "Unmarshalled transaction entry from pessimistic transaction [key="
                      + entry.key()
                      + ", value="
                      + entry.value()
                      + ", tx="
                      + tx
                      + ']');

            if (!tx.setWriteValue(entry))
              U.warn(
                  log,
                  "Received entry to commit that was not present in transaction [entry="
                      + entry
                      + ", tx="
                      + tx
                      + ']');
          }
        }

        // Add completed versions.
        tx.doneRemote(req.baseVersion(), req.committedVersions(), req.rolledbackVersions());

        if (tx.pessimistic()) tx.prepare();

        tx.commit();
      } else if (tx != null) {
        tx.doneRemote(req.baseVersion(), req.committedVersions(), req.rolledbackVersions());

        tx.rollback();
      }

      if (req.replyRequired()) {
        GridCacheMessage<K, V> res =
            new GridDistributedTxFinishResponse<K, V>(req.version(), req.futureId());

        try {
          ctx.io().send(nodeId, res);
        } catch (Throwable e) {
          // Double-check.
          if (ctx.discovery().node(nodeId) == null) {
            if (log.isDebugEnabled())
              log.debug(
                  "Node left while sending finish response [nodeId="
                      + nodeId
                      + ", res="
                      + res
                      + ']');
          } else
            U.error(
                log,
                "Failed to send finish response to node [nodeId=" + nodeId + ", res=" + res + ']',
                e);
        }
      }
    } catch (GridCacheTxRollbackException e) {
      if (log.isDebugEnabled())
        log.debug("Attempted to start a completed transaction (will ignore): " + e);
    } catch (Throwable e) {
      U.error(
          log,
          "Failed completing transaction [commit=" + req.commit() + ", tx=" + CU.txString(tx) + ']',
          e);

      if (tx != null) tx.rollback();
    }
  }
  /** {@inheritDoc} */
  @SuppressWarnings("BusyWait")
  @Override
  public void start(GridRestProtocolHandler hnd) throws GridException {
    InetAddress locHost;

    try {
      locHost = U.resolveLocalHost(ctx.config().getLocalHost());
    } catch (IOException e) {
      throw new GridException(
          "Failed to resolve local host to bind address: " + ctx.config().getLocalHost(), e);
    }

    System.setProperty(GG_JETTY_HOST, locHost.getHostAddress());

    jettyHnd =
        new GridJettyRestHandler(
            hnd,
            new C1<String, Boolean>() {
              @Override
              public Boolean apply(String tok) {
                return F.isEmpty(secretKey) || authenticate(tok);
              }
            },
            log);

    String jettyPath = ctx.config().getRestJettyPath();

    final URL cfgUrl;

    if (jettyPath == null) {
      cfgUrl = null;

      if (log.isDebugEnabled())
        log.debug("Jetty configuration file is not provided, using defaults.");
    } else {
      cfgUrl = U.resolveGridGainUrl(jettyPath);

      if (cfgUrl == null)
        throw new GridSpiException("Invalid Jetty configuration file: " + jettyPath);
      else if (log.isDebugEnabled()) log.debug("Jetty configuration file: " + cfgUrl);
    }

    loadJettyConfiguration(cfgUrl);

    AbstractNetworkConnector connector = getJettyConnector();

    try {
      host = InetAddress.getByName(connector.getHost());
    } catch (UnknownHostException e) {
      throw new GridException("Failed to resolve Jetty host address: " + connector.getHost(), e);
    }

    int initPort = connector.getPort();

    int lastPort = initPort + ctx.config().getRestPortRange() - 1;

    for (port = initPort; port <= lastPort; port++) {
      connector.setPort(port);

      if (startJetty()) {
        if (log.isInfoEnabled()) log.info(startInfo());

        return;
      }
    }

    U.warn(
        log,
        "Failed to start Jetty REST server (possibly all ports in range are in use) "
            + "[firstPort="
            + initPort
            + ", lastPort="
            + lastPort
            + ']');
  }
  /** {@inheritDoc} */
  @Override
  public GridDeployment getDeployment(GridDeploymentMetadata meta) {
    assert meta != null;

    assert ctx.config().isPeerClassLoadingEnabled();

    // Validate metadata.
    assert meta.classLoaderId() != null;
    assert meta.senderNodeId() != null;
    assert meta.sequenceNumber() >= -1;
    assert meta.parentLoader() == null;

    if (log.isDebugEnabled())
      log.debug("Starting to peer-load class based on deployment metadata: " + meta);

    while (true) {
      List<SharedDeployment> depsToCheck = null;

      SharedDeployment dep = null;

      synchronized (mux) {
        // Check obsolete request.
        if (isDeadClassLoader(meta)) return null;

        List<SharedDeployment> deps = cache.get(meta.userVersion());

        if (deps != null) {
          assert !deps.isEmpty();

          for (SharedDeployment d : deps) {
            if (d.hasParticipant(meta.senderNodeId(), meta.classLoaderId())
                || meta.senderNodeId().equals(ctx.localNodeId())) {
              // Done.
              dep = d;

              break;
            }
          }

          if (dep == null) {
            GridTuple2<Boolean, SharedDeployment> redeployCheck = checkRedeploy(meta);

            if (!redeployCheck.get1()) {
              // Checking for redeployment encountered invalid state.
              if (log.isDebugEnabled())
                log.debug("Checking for redeployment encountered invalid state: " + meta);

              return null;
            }

            dep = redeployCheck.get2();

            if (dep == null) {
              // Find existing deployments that need to be checked
              // whether they should be reused for this request.
              for (SharedDeployment d : deps) {
                if (!d.isPendingUndeploy() && !d.isUndeployed()) {
                  if (depsToCheck == null) depsToCheck = new LinkedList<SharedDeployment>();

                  if (log.isDebugEnabled()) log.debug("Adding deployment to check: " + d);

                  depsToCheck.add(d);
                }
              }

              // If no deployment can be reused, create a new one.
              if (depsToCheck == null) {
                dep = createNewDeployment(meta, false);

                deps.add(dep);
              }
            }
          }
        } else {
          GridTuple2<Boolean, SharedDeployment> redeployCheck = checkRedeploy(meta);

          if (!redeployCheck.get1()) {
            // Checking for redeployment encountered invalid state.
            if (log.isDebugEnabled())
              log.debug("Checking for redeployment encountered invalid state: " + meta);

            return null;
          }

          dep = redeployCheck.get2();

          if (dep == null)
            // Create peer class loader.
            dep = createNewDeployment(meta, true);
        }
      }

      if (dep != null) {
        if (log.isDebugEnabled())
          log.debug("Found SHARED or CONTINUOUS deployment after first check: " + dep);

        // Cache the deployed class.
        Class<?> cls = dep.deployedClass(meta.className(), meta.alias());

        if (cls == null) {
          U.warn(
              log,
              "Failed to load peer class (ignore if class got undeployed during preloading) [alias="
                  + meta.alias()
                  + ", dep="
                  + dep
                  + ']');

          return null;
        }

        return dep;
      }

      assert meta.parentLoader() == null;
      assert depsToCheck != null;
      assert !depsToCheck.isEmpty();

      /*
       * Logic below must be performed outside of synchronization
       * because it involves network calls.
       */

      // Check if class can be loaded from existing nodes.
      // In most cases this loop will find something.
      for (SharedDeployment d : depsToCheck) {
        // Load class. Note, that remote node will not load this class.
        // The class will only be loaded on this node.
        Class<?> cls = d.deployedClass(meta.className(), meta.alias());

        if (cls != null) {
          synchronized (mux) {
            if (!d.isUndeployed() && !d.isPendingUndeploy()) {
              if (!addParticipant(d, meta)) return null;

              if (log.isDebugEnabled())
                log.debug(
                    "Acquired deployment after verifying it's availability on "
                        + "existing nodes [depCls="
                        + cls
                        + ", dep="
                        + d
                        + ", meta="
                        + meta
                        + ']');

              return d;
            }
          }
        } else if (log.isDebugEnabled()) {
          log.debug(
              "Deployment cannot be reused (class does not exist on participating nodes) [dep="
                  + d
                  + ", meta="
                  + meta
                  + ']');
        }
      }

      // We are here either because all participant nodes failed
      // or the class indeed should have a separate deployment.
      for (SharedDeployment d : depsToCheck) {
        // Temporary class loader.
        ClassLoader temp =
            new GridDeploymentClassLoader(
                GridUuid.randomUuid(),
                meta.userVersion(),
                meta.deploymentMode(),
                true,
                ctx,
                ctxLdr,
                meta.classLoaderId(),
                meta.senderNodeId(),
                meta.sequenceNumber(),
                comm,
                ctx.config().getNetworkTimeout(),
                log,
                ctx.config().getPeerClassLoadingClassPathExclude(),
                0,
                false);

        String path = U.classNameToResourceName(d.sampleClassName());

        // We check if any random class from existing deployment can be
        // loaded from sender node. If it can, then we reuse existing
        // deployment.
        InputStream rsrcIn = temp.getResourceAsStream(path);

        if (rsrcIn != null) {
          // We don't need the actual stream.
          U.closeQuiet(rsrcIn);

          synchronized (mux) {
            if (d.isUndeployed() || d.isPendingUndeploy()) continue;

            // Add new node prior to loading the class, so we attempt
            // to load the class from the latest node.
            if (!addParticipant(d, meta)) {
              if (log.isDebugEnabled())
                log.debug(
                    "Failed to add participant to deployment "
                        + "[meta="
                        + meta
                        + ", dep="
                        + dep
                        + ']');

              return null;
            }
          }

          Class<?> depCls = d.deployedClass(meta.className(), meta.alias());

          if (depCls == null) {
            U.error(
                log,
                "Failed to peer load class after loading it as a resource [alias="
                    + meta.alias()
                    + ", dep="
                    + dep
                    + ']');

            return null;
          }

          if (log.isDebugEnabled())
            log.debug(
                "Acquired deployment class after verifying other class "
                    + "availability on sender node [depCls="
                    + depCls
                    + ", rndCls="
                    + d.sampleClass()
                    + ", sampleClsName="
                    + d.sampleClassName()
                    + ", meta="
                    + meta
                    + ']');

          return d;
        } else if (log.isDebugEnabled())
          log.debug(
              "Deployment cannot be reused (random class could not be loaded from sender node) [dep="
                  + d
                  + ", meta="
                  + meta
                  + ']');
      }

      synchronized (mux) {
        if (log.isDebugEnabled())
          log.debug(
              "None of the existing class-loaders fit (will try to create a new one): " + meta);

        // Check obsolete request.
        if (isDeadClassLoader(meta)) return null;

        // Check that deployment picture has not changed.
        List<SharedDeployment> deps = cache.get(meta.userVersion());

        if (deps != null) {
          assert !deps.isEmpty();

          boolean retry = false;

          for (SharedDeployment d : deps) {
            // Double check if sender was already added.
            if (d.hasParticipant(meta.senderNodeId(), meta.classLoaderId())) {
              dep = d;

              retry = false;

              break;
            }

            // New deployment was added while outside of synchronization.
            // Need to recheck it again.
            if (!d.isPendingUndeploy() && !d.isUndeployed() && !depsToCheck.contains(d))
              retry = true;
          }

          if (retry) {
            if (log.isDebugEnabled()) log.debug("Retrying due to concurrency issues: " + meta);

            // Outer while loop.
            continue;
          }

          if (dep == null) {
            // No new deployments were added, so we can safely add ours.
            dep = createNewDeployment(meta, false);

            deps.add(dep);

            if (log.isDebugEnabled())
              log.debug(
                  "Adding new deployment within second check [dep=" + dep + ", meta=" + meta + ']');
          }
        } else {
          dep = createNewDeployment(meta, true);

          if (log.isDebugEnabled())
            log.debug(
                "Created new deployment within second check [dep=" + dep + ", meta=" + meta + ']');
        }
      }

      if (dep != null) {
        // Cache the deployed class.
        Class<?> cls = dep.deployedClass(meta.className(), meta.alias());

        if (cls == null) {
          U.warn(
              log,
              "Failed to load peer class (ignore if class got undeployed during preloading) [alias="
                  + meta.alias()
                  + ", dep="
                  + dep
                  + ']');

          return null;
        }
      }

      return dep;
    }
  }