Design Patterns
PART 2
Nirdosh, Milan
Strategy Pattern
Intent:
"Define a family of algorithms, encapsulate each one, and make them interchangeable. Strategy lets the algorithm very independently from clients use it "
Also known as Policy.
Strategy without Pattern:
Open Close Principal : Software Entities should be open for extension, but closed for modification
Non Usable: Strategy is not usable by any other context
Strategy with Pattern:
Applicability
- Many related classes differ only in their behavior
- You need a different variant of an algorithm
- To avoid exposing complex, algorithm-specific structures
- Avoid class with many if -else statements
Consequences
- Families of related algorithms
- An alternative to Subclassing
- Eliminates conditional statements
- Client must be aware of strategies
Challenge ...
