Project Streaming Refactorings

Perform the following refactorings to the Project Streaming codebase.

• In the method Account::report() lines 94-97, the variable time is used for two different purposes. Perform an Introduce Explaining Variable that adds a new variable to make this part of the code easier to understand.
• In the class Video, the two attributes lengthHours and lengthMinutes always occur together. Perform an Extract Class to combine these into a single class, Duration, with minutes and hours as attributes.
• In the method Account::report(), apply an Extract Method to extract a new method getNumberOfStreams() from the code in the loop that computes the number of streams.
• In the method Account::report(), apply an Extract Method to extract a new method getNumberOfOriginals() from the code in the loop that computes the number of originals.
• The methods extracted in the previous two steps are located in the class Account but focus all their attention on the class Video. So use a Move Method to move these methods from class Account to class Video. Note: The alternative is to move these methods to class Stream. Either move is acceptable.
• In Account::data(), apply an Extract Method to extract a new method, getStreamType() from the code in the loop that determines the stream type.
• The extracted method primarily works with the class Video, so apply a Move Method to move the method to the class Video.

• Big Refactoring

  The class Video has a type attribute that determines what it is: (Movie, TV, or Original). A switch statement selects the proper logic, a classic sign of poor abstraction and design. Instead, the code should use subclassing and virtual methods to address this problem. Do so by performing the following separate steps:

  • Create three new classes, Movie, TV, and Original, that inherit from the class Video.
  • Perform a Replace Type Code with Subclasses on the class Video and classes Movie, TV, and Original.
  • Perform a Replace Conditional with Polymorphism in getNumberOfStreams(), getNumberOfOrginals(), and getStreamType().
  • Perform a Push Method Down on all three methods (making them virtual) into the appropriate subclass. In the class Video, these methods would be a pure virtual methods, making the class Video abstract.