presto-main/src/main/java/io/prestosql/split/PageSourceManager.java/PageSourceManager/getPageSourceProvider
class PageSourceManager:    private ConnectorPageSourceProvider getPageSourceProvider(CatalogName catalogName)
    {
        ConnectorPageSourceProvider provider = pageSourceProviders.get(catalogName);
        checkArgument(provider != null, "No page source provider for connector: %s", catalogName);
        return provider;
    }