@VisibleForTesting
  public void stopStores() {
    this.taskStores.forEach((taskName, storeMap) -> storeMap.forEach((storeName, store) -> store.stop()));
  }
Set of directory paths for all stores restored by this {@link ContainerStorageManager}.
@return the set of all store directory paths
samza-core/src/main/scala/org/apache/samza/storage/ContainerStorageManager.java