Structural Design Patterns

Question 1

Name all the gof structural design patterns

Answer 1

Adapter
Bridge
Composite
Decorator
Facade
Flyweight
Proxy

Question 2

Give an example of a bridge pattern

Answer 2

Composition over inheritance- this refers to a “has a” relationship between two items that could change instead of something hardwired or inherited. Example is a remote has a car.

Question 3

Give an example of a proxy pattern

Answer 3

Apigee is a proxy pattern. Exposes the entire interface (and does some of its own stuff) diff from a facade bc a facade simplifies.

Question 4

Give an example of a facade pattern

Answer 4

Ocr submission class. Lots of private methods under the hood but externally you just call ‘submit’.

Question 5

Give an example of a composite pattern

Answer 5

A structure where limbs and nodes all extend an abstract class so it can be crawled. VPs and departments.

Question 6

Give an example of a decorated pattern

Answer 6

Open for extension, closed for modification. Example is wrapper classes like Christmas tree interface that’s implemented by tree, garland, and bulbs. Allows class to be dynamically changed at runtime

Question 7

Give an example of an adaptor pattern

Answer 7

Gives a bridge from one class to another. Mapping in rxjs subscriptions.

Question 8

Give an example of a flyweight pattern

Answer 8

Lightweight representation of heavy objects.