presto-spi/src/main/java/io/prestosql/spi/connector/CatalogSchemaName.java/CatalogSchemaName/CatalogSchemaName
class CatalogSchemaName:    public CatalogSchemaName(String catalogName, String schemaName)
    {
        this.catalogName = requireNonNull(catalogName, "catalogName is null").toLowerCase(ENGLISH);
        this.schemaName = requireNonNull(schemaName, "schemaName is null").toLowerCase(ENGLISH);
    }