public void addContainerStorageStats(String partitionClassName, long partitionId, short accountId,
      ContainerStorageStats stats) {
    storageStats.computeIfAbsent(partitionClassName, k -> new HashMap<>())
        .computeIfAbsent(partitionId, k -> new HashMap<>())
        .computeIfAbsent(accountId, k -> new HashMap<>())
        .put(stats.getContainerId(), stats);
  }
Add container storage stats to this {@link HostPartitionClassStorageStats}.
@param partitionClassName The partition class name
@param partitionId The partition id
@param accountId The account id
@param stats The container stats
ambry-api/src/main/java/com/github/ambry/server/storagestats/HostPartitionClassStorageStats.java