The state pattern is a behavioral design pattern. According to GoF definition, a state allows an object to alter its behavior when its internal state changes. The object will appear to change its class. It can be drawn from above definition that there shall be a separate concrete class per possible state of an object. […]
Mediator Design Pattern
Mediator helps in establishing loosely coupled communication between objects and helps in reducing the direct references to each other.
Observer Design Pattern
According to GoF definition, observer pattern defines a one-to-many dependency between objects so that when one object changes state, all its dependents are notified and updated automatically. It is also referred to as the publish-subscribe pattern. In observer pattern, there are many observers (subscriber objects) that are observing a particular subject (publisher object). Observers register […]
Memento Design Pattern
Memento design pattern is behavioral pattern and one of 23 design patterns discussed by Gang of Four. Memento pattern is used to restore state of an object to a previous state. It is also known as snapshot pattern. A memento is is like a restore point during the life cycle on the object, which the […]
Iterator Design Pattern
An iterator design pattern provides a way to access the elements of an aggregate object sequentially without exposing its underlying representation.
Command Design Pattern
Command pattern is a behavioral design pattern which is useful to abstract business logic into discrete actions i.e. commands. It motivates loose coupling.
Strategy Design Pattern
Strategy design pattern is behavioral design pattern where we choose a specific implementation of algorithm or task in run time – out of multiple other implementations for same task.
Template Method Design Pattern
Template method design pattern is widely accepted behavioral design pattern to enforce some sort of algorithm (fixed set of steps) in the context of programming. It defines the sequential steps to execute a multi-step algorithm and optionally can provide a default implementation as well (based on requirements). Table of Contents Introduction Problem Statement Solution Code […]
Visitor Design Pattern Example
Design patterns are used to solve the problems which occur in a pattern, we all know that, right? Also we know that behavioral design patterns are design patterns that identify common communication patterns between objects. One of such behavioral patterns is visitor pattern, which we are going to learn about in this post. If you […]
Chain of Responsibility Design Pattern
The Chain of Responsibility is known as a behavioral pattern. The main objective of this pattern is that it avoids coupling the sender of the request to the receiver, giving more than one object the opportunity to handle the request. The core logic defined by GoF is : “Gives more than one object an opportunity […]