Behavioral Design Patterns in C++ - Document Framework - I

The video tutorial explains the Template Method design pattern, commonly used in frameworks to allow basic implementation customization. It provides an example of a framework class that users can extend to define their own file types. The tutorial focuses on implementing a document class with a stream object and a boolean to track modifications. Clients can subclass this document class to create specific document types, such as a text document, by overriding save and load methods. The tutorial demonstrates how to implement these methods, handle file operations, and use the framework effectively.

What is the primary purpose of the Template Method design pattern in frameworks?

• To provide a complete implementation that cannot be modified.

• To offer a basic implementation that users can customize.

• To enforce strict rules on how classes should be used.

• To allow users to define their own classes from scratch.

What does the Document class provide to its subclasses?

• A method to delete documents.

• A stream object for saving document state.

• A fixed document format.

• A user interface for document editing.

How does a client use the framework to create a TextDocument?

• By creating a new class unrelated to Document.

• By directly modifying the Document class.

• By using a pre-defined TextDocument class.

• By inheriting from the Document class and overriding methods.

What is the purpose of the 'ismodified' boolean in the Document class?

• To track if the document is currently open.

• To indicate if the document has unsaved changes.

• To specify the document's file format.

• To determine the document's size.

What happens if a file is modified and a new file is attempted to be loaded?

• The application crashes.

• A message prompts to save current changes first.

• The new file is loaded without any warning.

• The modified file is automatically saved.

What is the role of the 'seek P' function in the save method?

• To position the write pointer at the beginning of the file.

• To move the write pointer to the end of the file.

• To check for file errors.

• To close the file after writing.

Why is the protected access modifier used in the Document class?

• To prevent any access to the variables.

• To hide variables from the Document class itself.

• To make variables accessible to all classes.

• To allow subclasses to access certain variables.