The DB and DBTable classes remain the same, and we added an abstract class DBStorage to the project. The DB class inherits DBStorage, which works as a concrete class, and we created a DBDecorator inheriting the DBStorage as a root class of decorators. DBDecorator also have an instance field of DBStorage, which stores the DB, and DBDecorator delegates its methods. ConsoleLoggingDBDecorator and FileLoggingDBDecorator works properly to record in console or file.