@Override
  public Store getStore(PartitionId id) {
    try {
      lock.readLock().lock();
      if (partitionToStore.containsKey(id)) {
        return partitionToStore.get(id).isStarted() ? partitionToStore.get(id) : null;
      }
    } finally {
      lock.readLock().unlock();
    }
    return createAndStartBlobStoreIfAbsent(id);
  }
Returning null because this will not be used as part of CloudStorageManager Implementation.
Implementation will be added if needed.
ambry-cloud/src/main/java/com/github/ambry/cloud/CloudStorageManager.java