Understanding the 23 Gang of Four (GoF) design patterns

Understanding the 23 Gang of Four (GoF) design patterns

In this post, we will discuss what the GoF design patterns are? Where they are used? Why they are used? How they can help developers and projects?

But First, What are Design Patterns and how do they fit in Software Engineering?

In software engineering, design patterns are part of the larger concept of software design. Software design refers to the process of creating a plan or blueprint for the software to be developed. Design patterns are one of the tools used by software engineers to help them create this plan.

The use of design patterns in software engineering has several benefits. First, design patterns provide a common vocabulary for discussing software design. This helps to improve communication between team members and makes it easier to understand the design decisions made by others. Second, design patterns provide a set of best practices that have been proven to work in the past. This makes it easier for software engineers to create software that is robust, reliable, and maintainable. Finally, design patterns help to promote code reuse, which can save time and effort in the long run.

Ok, I got that! Now, what are these GoF Design Patterns? Are there other design patterns than the 23 of GoF?

These patterns were first introduced by the Gang of Four (GoF), a renowned group of software developers who wrote a book on design patterns in 1994. These patterns are divided into three categories: creational patterns, structural patterns, and behavioral patterns. Creational patterns deal with object creation and initialization, Structural patterns deal with the composition of classes and objects and Behavioral patterns deal with communication and interaction between objects.

In addition to these 23 GoF patterns, there are other design patterns that have been developed and documented by software engineers and architects over the years. However, the GoF patterns remain the most widely used and recognized patterns in the software development industry.

Cool, so where are the GoF Design Patterns used?

The GoF design patterns are used in a wide variety of software development projects, including web applications, desktop applications, mobile applications, and games. They are used in any situation where a developer wants to solve a common software development problem in a standard and repeatable way.

Also, how can the GoF Design Patterns help Developers like me and our Projects?

The GoF design patterns can help developers and projects in several ways. First, they can help developers write better code by providing a standard way to solve common software development problems. Second, they can save time and effort by promoting code reuse. Third, they can help projects stay on schedule and within budget by avoiding common mistakes and pitfalls in software development.

When to Use the GoF Design Patterns?

The GoF design patterns should be used when the developer is facing a common software development problem that has already been solved by one of the patterns. They should not be used when the developer is trying to solve a unique or unusual problem, as the patterns may not be appropriate or helpful in this case.

Are the 23 GoF design patterns still relevant in modern software development, or have they been superseded by newer approaches?

The 23 GoF design patterns are still highly relevant in modern software development, and they continue to be widely used and studied by developers. They provide proven solutions to common problems and can be applied to a wide range of programming languages and frameworks. However, it's worth noting that newer approaches and patterns have emerged in recent years. For example, there are patterns specifically tailored to reactive programming or cloud-based architectures and some developers may choose to use different patterns depending on their specific project requirements or preferences. Nevertheless, the GoF design patterns remain a valuable tool for developers, and their concepts are still highly applicable and relevant in modern software development.

Now, I have understood the motive and I am interested to learn them. Tell me more about them.

These 23 patterns are categorized into three groups:

  1. Creational Patterns (5): These patterns deal with object creation mechanisms, trying to create objects in a manner suitable to the situation.

  2. Structural Patterns (7): These patterns deal with object composition, to form large structures from small ones.

  3. Behavioral Patterns (11): These patterns deal with communication between objects, how they cooperate, and how they operate to perform a task.

We will now discuss each of these groups in detail but to avoid making the post much bigger, boring and to give you a little break further discussion is in next post.