This class provides an empty implementation of IdentifierParserVisitor,
which can be extended to create a visitor which only needs to handle a subset
of the available methods.
This class provides an empty implementation of IoTDBSqlParserVisitor,
which can be extended to create a visitor which only needs to handle a subset
of the available methods.
This class provides an empty implementation of PathParserVisitor,
which can be extended to create a visitor which only needs to handle a subset
of the available methods.