Factory Method Pattern

The Factory Method Pattern lets a subclass decide which concrete type to create, without the class that uses it ever naming that type.

A class often needs to make an object without knowing which one. A report generator produces a document. A parser builds a node. A notification service creates a message. The moment you write new PdfDocument() inside the report generator, that generator is welded to PDF, and adding HTML output means editing a class that already works and is already tested.

Consider a ReportGenerator