presto-raptor-legacy/src/main/java/io/prestosql/plugin/raptor/legacy/RaptorConnectorFactory.java/RaptorConnectorFactory/RaptorConnectorFactory
class RaptorConnectorFactory:    public RaptorConnectorFactory(String name, Module metadataModule, Map<String, Module> backupProviders)
    {
        checkArgument(!isNullOrEmpty(name), "name is null or empty");
        this.name = name;
        this.metadataModule = requireNonNull(metadataModule, "metadataModule is null");
        this.backupProviders = ImmutableMap.copyOf(requireNonNull(backupProviders, "backupProviders is null"));
    }