/**
   * @param alias Class alias.
   * @return Deployed class.
   */
  @Nullable
  private GridDeployment getDeployment(String alias) {
    assert Thread.holdsLock(mux);

    LinkedList<GridDeployment> deps = cache.get(alias);

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

      GridDeployment dep = deps.getFirst();

      if (!dep.isUndeployed()) {
        return dep;
      }
    }

    return null;
  }