Behavioral Flashcards
Observer
Define a one-to-many dependency between objects so that when one object changes states, all its dependents are notified and updated automatically
Command
Encapsulate a request as an object, thereby letting us parameterize clients with different requests, queue or log requests, and support undoable operations.
Iterator
Provide a way to access the elements of an aggregate object sequentially without exposing its underlying representation.
Memento
Without violating encapsulation, capture and externalize an object’s internal state so that the object can be restored to this state later.
Template Method
Define the skeleton of an algorithm in an operation, deferring some steps to subclasses. Let subclasses redefine certain steps of an algorithm without changing the algorithm’s structure.
Chain of Responsibility
Avoid coupling the sender of a request to its receiver by giving more than one object a chance to handle the request. Link the receiving objects and pass the request along the list until an object handles it.
Strategy
Define a family of algorithms, encapsulate each one, and make them interchangeable. Let the algorithm vary independently from clients that use it.
State
Allow an object to alter its behavior when its internal state changes. The object will appear to change its class.
Visitor
Represent an operation to be performed on the elements of an object structure. Let us define a new operation without changing the classes of the elements on which it operates.
Interpreter
Given a language, define a representation for its grammar along with a processor that uses the representation to parse sentences in the language
Mediator
Define an object that encapsulates how a set of objects interact. Promotes loose coupling by keeping objects from referring to each other explicitly, and lets you vary their iteraction independently.
