/**
   * @param key Removed key.
   * @param ver Removed version.
   * @throws IgniteCheckedException If failed.
   */
  public void onDeferredDelete(KeyCacheObject key, GridCacheVersion ver)
      throws IgniteCheckedException {
    try {
      T2<KeyCacheObject, GridCacheVersion> evicted = rmvQueue.add(new T2<>(key, ver));

      if (evicted != null) cctx.dht().removeVersionedEntry(evicted.get1(), evicted.get2());
    } catch (InterruptedException e) {
      Thread.currentThread().interrupt();

      throw new IgniteInterruptedCheckedException(e);
    }
  }
  /**
   * @param entry Entry to enlist.
   * @throws IgniteCheckedException If failed.
   * @return {@code True} if entry was enlisted.
   */
  private boolean addEntry(IgniteTxEntry entry) throws IgniteCheckedException {
    checkInternal(entry.txKey());

    GridCacheContext cacheCtx = entry.context();

    if (!cacheCtx.isNear()) cacheCtx = cacheCtx.dht().near().context();

    GridNearCacheEntry cached = cacheCtx.near().peekExx(entry.key());

    if (cached == null) {
      evicted.add(entry.txKey());

      return false;
    } else {
      cached.unswap();

      try {
        CacheObject val = cached.peek(true, false, false, null);

        if (val == null && cached.evictInternal(false, xidVer, null)) {
          evicted.add(entry.txKey());

          return false;
        } else {
          // Initialize cache entry.
          entry.cached(cached);

          writeMap.put(entry.txKey(), entry);

          addExplicit(entry);

          return true;
        }
      } catch (GridCacheEntryRemovedException ignore) {
        evicted.add(entry.txKey());

        if (log.isDebugEnabled())
          log.debug("Got removed entry when adding to remote transaction (will ignore): " + cached);

        return false;
      }
    }
  }