presto-main/src/main/java/io/prestosql/split/SplitManager.java/SplitManager/addConnectorSplitManager
class SplitManager:    public void addConnectorSplitManager(CatalogName catalogName, ConnectorSplitManager connectorSplitManager)
    {
        requireNonNull(catalogName, "catalogName is null");
        requireNonNull(connectorSplitManager, "connectorSplitManager is null");
        checkState(splitManagers.putIfAbsent(catalogName, connectorSplitManager) == null, "SplitManager for connector '%s' is already registered", catalogName);
    }