Behavioral patterns
Introduction
Behavioral patterns, in the context of software design, are a type of design patterns that identify common communication patterns between objects and realize these patterns. By doing so, these patterns increase flexibility in carrying out communication.
Overview
Behavioral patterns are concerned with algorithms and the assignment of responsibilities between objects. They deal with the process of objects in a system communicating, handling data, and distributing tasks. These patterns are used to ensure that components of a system function together as a cohesive whole, while still maintaining loose coupling.
Types of Behavioral Patterns
There are several types of behavioral patterns used in software design. Each has a unique way of solving communication problems between objects.
Observer Pattern
The observer pattern is a software design pattern in which an object, named the subject, maintains a list of its dependents, called observers, and notifies them automatically of any state changes, usually by calling one of their methods.
State Pattern
The state pattern is a behavioral design pattern that allows an object to alter its behavior when its internal state changes. The object will appear to change its class.
Strategy Pattern
The strategy pattern is a type of behavioral pattern that enables selecting an algorithm at runtime. Instead of implementing a single algorithm directly, code receives run-time instructions as to which in a family of algorithms to use.
Template Method Pattern
The template method pattern is a behavioral design pattern that defines the program skeleton of an algorithm in a method, called template method, which defers some steps to subclasses.
Visitor Pattern
The visitor pattern is a way of separating an algorithm from an object structure on which it operates. A practical result of this separation is the ability to add new operations to existing object structures without modifying those structures.
Advantages of Behavioral Patterns
Behavioral patterns offer several advantages in software design. They provide clear, flexible ways to carry out communication between objects in a system. They also ensure that the system is loosely coupled, meaning that individual objects can function independently of others.
Disadvantages of Behavioral Patterns
Despite their advantages, behavioral patterns also have some disadvantages. They can add complexity to a system, as they often involve more classes and objects than other types of patterns. They can also be difficult to understand and implement correctly, especially for less experienced developers.
Conclusion
Behavioral patterns play a crucial role in software design, enabling efficient communication between objects and ensuring that systems function as cohesive wholes. Despite their complexity, they offer significant benefits and are an essential tool for any software developer.