A listener that observers changes of a Database . A change_listener shall not observe multiple Databases or be registered at a Database multiple times. If this object is registered multiple times to one or more Databases , then this observer may (depending on the program's configuration) notice this fact and throw an exception.
Registers the given line that was added to the observed Database .
Implements the functionality of register_addition(Line line) for multiple line additions. This can be used in order to optimize performance by grouping incoming events.
Registers the given line that was removed from the Database .
Implements the functionality of register_removal(Line line) for multiple line additions. This can be used in order to optimize performance by grouping incoming events.
The object that is observed by this.