public StorageEngine getStore(String storeName) {
    return stores.get(storeName);
  }
Gets the {@link StorageEngine} associated with the input {@code storeName} if found, or null.

@param storeName store name to get the {@link StorageEngine} for
@return the {@link StorageEngine} associated with {@code storeName} if found, or null
samza-core/src/main/java/org/apache/samza/storage/TaskSideInputStorageManager.java