Object-Oriented Programming (OOP) is one of the top famous techniques in Software Engineering. OOP is built on top of objects and classes. The concept behind the OOP is to map programming objects with real-world objects, things, or concepts. You can find object oriented programming books below for more information. here I try to explain the concepts with object oriented programming java examples. Let’s first learn what is object oriented programming.
Object-oriented programming out looks just like building blocks. Consider we want to build a house. We can consider the house as a single object end of the build process. But it’s built on a collection of different objects like windows, doors, walls, etc. In the same way, windows are built using Glass, Iron frames, etc.
We use the same manner with programming on Object-oriented programming. Applications build on Objects inside objects. When comes to the programming real-world every tangible item or intangible things consider an object, and those objects contain different types of behaviors, attitudes, and characteristics.
There are a lot of methodologies, concepts, and principles to follow when building a good application. Below are the main four participants when programming. This paradigm is used by different programming languages in different approaches.
- Class
- Objects
- Function or methods
- Attributes
What is Class in OOP?
Class is a blueprint of the object. Classes can contain functions or methods. These are representing the behaviors of objects. Class properties represent using attributes. Classes use to create each individual object.
// Initializing Class
class Car{}When considering the real object car. Cars have basic functions like accelerating, stopping, change Gear. There are attributes like tire count, seat count, and a lot more.
What is an Object in OOP?
An object is something like a real-world thing or an item. It creates an instance of a class. Objects are created separately for every single thing but, when considering the single object may vary with other objects. Therefore each object could be unique or different.
Let’s consider the above car class and create separate two objects for BMW and CIVIC. There are some behaviors and attribute with cars, but values are changed between CIVIC and BMW.
// New civic object create using Car Class (Blue Print) Car civic= new Car(); // New bmw object create using Car Class (Blue Print) Car bmw= new Car()
What is Attribute in OOP?
Attributes are characteristics or properties of objects. Those are defined in a class. Attributes have different access types according to the programming language. Attributes values are able to modify after creating an object.
// Name of the class
class Cat {
//Attribute of Cat class - type Public
public String color;
public int age;
public int legs;
}
What is Method or Function in OOP?
Use methods to define the behavior of objects. Methods have different access levels according to the languages. The method is to do some functionality and return some output.
// Name of the class
class Cat {
//Attribute of Cat class
public String color;
// Method of Cat class
public String speak(){
return "Meaw";
}
public String toString(){
return color;
}
}
public class Oop {
public static void main(String[] args) {
// Create object using Cat class
Cat cat1 =new Cat();
Cat cat2 =new Cat();
cat1.color="Black";
cat2.color="White";
// Cat1 and Cat2 Use same Cat class( Blueprint) to declare two different cats
System.out.println("Cat color "+cat1);
System.out.println("Cat color "+cat2);
}
}// Cat color Black Cat color White
What are the main four Object-Oriented Programming concepts?
- Abstraction: The concept of abstraction is showing the required information to the outside and hiding the low-level complex implementation.
- Encapsulation: Everything (data-attributes / behaviors- method or function) combine and keep together as a single unit.
- Inheritance: Acquiring all the behaviors and attributes from another which means programming one class properties derived from another class.
- Polymorphism: Polymorphism easily says a single class or object ability to play as many forms. In other words, there can be more characteristics with one class according to the situation.
What are the advantages of OOP?
There are so many advantages in OOP, but here just shows high-level advantages. By using these concepts, it is possible to make applications very strong and smart.
- OOP used to make application security
- Complex procedural program changes to simple blocks of structures.
- Improve code reusability
- Easy to debug and easy to maintain
- Easy to extend and easy to understand
object oriented programming books
Summary
OOP programming is every programmer’s touch in their life when starting the programming. Nowadays it’s the most popular programming concept used by most popular languages like Java, PHP, C#, .Net, Python, and a lot more. Their syntax may change but the concept behind usability is the same.
