Category Archives: Software Engineering

Software Design Patterns

Software Engineering

Software design patterns are essential tools for developers, allowing them to build robust and scalable applications. They provide tried and tested solutions to common software development problems, saving time and effort while ensuring the quality of the code. In this article, we will explore the basics of software design patterns and their importance in modern software development.

Types of Design Patterns

There are three main categories of software design patterns:

Creational patterns

Creational patterns provide solutions for object creation mechanisms, trying to create objects in a manner suitable for the situation. These patterns deal with the process of object creation in such a way that they can be decoupled from the code that uses them.

Structural patterns

Structural patterns focus on the composition of classes and objects to form larger structures. These patterns help developers create large-scale software architectures by arranging and organizing different components.

Behavioral patterns

Behavioral patterns provide solutions for the interaction between objects, focusing on communication between different classes and objects. These patterns define the ways in which objects communicate with each other and how they can be modified to achieve specific results.

Importance of Software Design Patterns

Design patterns are important in software development for several reasons:

They improve the quality of the code

By following well-established design patterns, developers can write clean and organized code that is easier to read, maintain, and scale. Design patterns help developers avoid common coding mistakes and prevent bugs and errors.

They save development time

Design patterns provide proven solutions to common problems, reducing the time and effort required to solve them. Developers can use these patterns to streamline the development process and focus on the unique aspects of their application.

They promote collaboration

Design patterns are widely used and recognized in the software development industry, making it easier for developers to collaborate on large-scale projects. By using standard patterns, developers can communicate more effectively and work together more efficiently.

Examples of Software Design Patterns

Singleton

Singleton is a creational pattern that ensures a class has only one instance, providing a global point of access to it. This pattern is used to ensure that a particular class is instantiated only once, providing centralized control over a resource.

Decorator

The Decorator pattern is a structural pattern that allows developers to add functionality to an object at runtime, without changing its underlying structure. This pattern is often used in GUI programming to add new features to a user interface.

Observer

The Observer pattern is a behavioral pattern that defines a one-to-many dependency between objects, so that when one object changes state, all its dependents are notified and updated automatically. This pattern is often used in event-driven systems, such as user interfaces, to synchronize different components.

Conclusion

Software design patterns are essential tools for developers, providing well-established solutions to common problems encountered in software development. By using design patterns, developers can write clean, organized, and efficient code, saving time and effort while ensuring the quality of the application. Design patterns are widely recognized in the software development industry, promoting collaboration and communication between developers. As software applications become more complex, design patterns will continue to play an important role in software development, helping developers build robust and scalable applications.

Motivation behind using Object Oriented Programming (OOP)

Software Engineering

Simplicity
One important way to deal with complexity is to reduce it to something simpler.
Divide and conquer principle: Divide the original problem into separate sub-problems that can be solved individually.

Maintainability
We must also be able to maintain and extend the solution in an evolving world. So it is important that the use OOP not only solve the problem, but also result in a program that can be maintained.

Reusability
When you divide problems into sub-problems, you will sometimes see similar sub-problems. Then it would be nicer to reuse a similar solution.

Flexibility
It is also desirable that your software is flexible. You may for example need to deliver several variants of your software to different customers.
Or you may need to reconfigure the software to a changed context. Also some of your shared sub-solutions may need to go into contexts that are not completely the same.

Difference between Class and Object

OOP, Software Engineering

Class vs Object
A class is a Blue print of an object. a general concept (like an Animal), an object is a very specific embodiment of that class, with a limited lifespan (like a lion, cat, or a zebra).

Class

  1. Definition: Class is mechanism of binding data members and associated methods in a single unit.
  2. Existence: It is logical existence
  3. Lifespan: Classes do not have a lifespan
  4. Memory Allocation: Memory space is not allocated , when it is created.
  5. Declaration/Definition: Definition is created once.

Object

  1. Definition: Instance of class or variable of class.
  2. Existence: It is physical existence
  3. Lifespan: Objects have a lifespan
  4. Memory Allocation: Memory space is allocated, when it is created.
  5. Declaration/Definition: it is created many time as you require.

What is Software Architecture?

Software Engineering

What is Software Architecture?

Software application architecture is the process of defining a structured solution that meets all of the technical and operational requirements, while optimizing common quality attributes such as performance, security, and manageability. It involves a series of decisions based on a wide range of factors, and each of these decisions can have considerable impact on the quality, performance, maintainability, and overall success of the application.

Philippe Kruchten, Grady Booch, Kurt Bittner, and Rich Reitman derived and refined a definition of architecture based on work by Mary Shaw and David Garlan (Shaw and Garlan 1996). Their definition is:

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Software design vs software architecture

Software Engineering

Architecture usually deals with what (is done) and where (it is done), but on the other hand, Design deals how(it is done).

Architecture is Highest level of abstraction of system, kind of skeleton. MVC, MOVE, 3-Tier, Service Oriented Architecture are architectural patterns exactly like different design patterns.

Software Design is about designing individual class/ modules / components and their responsibilities and functions.