OOPS (Object Oriented Programming) Concept in Java with Examples

Object Oriented Programming (OOP) is one of the essential concepts in programming. While Simula is the first object-oriented programming language, Smalltalk is the first truly object oriented programming language. Some other object-oriented programming languages are Java, C++, PHP, Python, and more. In this article, we will discuss the OOPs concept in Java. 

What is OOPs Concept (Object Oriented Programming System)?

Object oriented programming is a paradigm surrounding the use of objects to represent and adjust data. In OOP, data gets encapsulated within objects. Objects are described according to their behaviors and properties. OOP comes with various key concepts that allow developers to write reusable, modular, and maintainable code. 

You should also learn about Arrays in Data Structure: A Guide with Examples. 

What Are OOPs Concepts in Java?

OOPs in Java is useful for improving code readability and reusability with an efficient definition of a program. The primary OOPs concepts in Java include abstraction, encapsulation, inheritance, and polymorphism. The different Java OOPs concepts enable us to establish working methods and variables. 

After that, all the variables and methods can be reused without security taking a backseat. Understanding what is object oriented programming in Java is crucial for developing a strong knowledge of Java.

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List of OOPs Concepts in Java

Let us learn about all the Java OOPs concepts below:

1. Classes
2. Objects
3. Inheritance 
4. Polymorphism
5. Abstraction
6. Encapsulation
7. Association
8. Aggregation
9. Composition

• Class

  Class is one of the OOPs in Java, which refers to a collection of objects. A class is a logical entity. It is one of the OOPs concepts in Java, with examples like the creation of a blueprint from which an individual object can be developed. 

• Object

  In object oriented programming, anything that has a state and behavior falls under the category of an object. It is one of the OOPs concepts in Java that can either be physical or logical. These Java OOPs concepts can communicate without learning the details about each other’s code or data. It is one of the OOPs concepts in Java, with examples like a dog or a bike, because they have states and behavior. 

• Inheritance

  Inheritance refers to objects acquiring the behaviors and properties of a parent object. It is an OOPs concept in Java with reusable code. These Java OOPs concepts are useful for achieving runtime polymorphism. It is often easy to understand the OOPs concepts in Java with examples.    

• Polymorphism

  Polymorphism is an OOPs concept in Java that revolves around performing one task in multiple ways. For instance, you might try to convince a customer in different ways. In Java object oriented programming, overloading and overriding methods are used to achieve polymorphism. 

• Abstraction

  In object oriented programming, abstraction involves showing functionality while hiding internal details. Java OOPs concepts use abstract classes and interfaces to achieve abstraction.

• Encapsulation

  Encapsulation is an OOPs concept in Java that involves binding code and data together in a single unit. If you want to understand these OOPs concepts in Java with examples, you should consider a Java class. Java Bean can be described as a fully encapsulated class because all the data members are private. 

• Association

  The OOPs concept in Java that signifies the relationship between the objects is called association. This OOPs concept in Java ensures that an object can be associated with one single object or multiple objects. 

• Aggregation

  Aggregation is the OOPs concept in Java that paves the path for achieving association. Aggregation is symbolic of the weak relationship between objects. This OOPs concept in Java is symbolic of the relationship where one object contains other objects as a part of the state.

• Composition

  In Java object oriented programming, multiple ways to achieve association are present. Composition is yet another way of achieving association. It is one of the Java OOPs concepts that represent the strong relationship between the dependent object and the containing object. 

Advantages of OOPs Concept (Object-Oriented Programming System)

Once you know what is object oriented programming in Java, you should learn about its multiple advantages:

• Reusability

  A reusable code is something that’s written once but used multiple times. The use of class ensures that a particular code can be used an infinite number of times. 

• Data Redundancy

  One of the greatest advantages of Java OOPs concepts is data redundancy. It can be created at the data storage by holding the same piece of data in two different places. When you wish to utilize similar functionality in multiple classes, you can write common class definitions by inheriting them. 

• Code Maintenance

  The OOPs concept in Java makes it easy to maintain existing code as new objects can be created with minor differences from the existing ones. It enables users to rework multiple times and alter the existing code by incorporating new changes. 

• Security

  The Java OOPs concepts like abstracting and data hiding allow filtering out limited exposure. Therefore, the features of OOPs make only necessary data visible to maintain security. 

• Design Benefits

  The OOPs in Java enable designers to have a more extensive design phase. It leads to the creation of better designs. The program reaches critical limits after a certain amount of time. At that point, it becomes easy to program all non-oops individually. 

• Easy Troubleshooting

  The OOPs concept in Java enables the use of self-constrained encapsulation objects. Therefore, developers can easily solve ongoing issues. The features of OOPs also prevent the issue of duplicate codes. 

Disadvantages of OOPs Concept (Object-Oriented Programming System)

Once you understand what is object oriented programming in Java and its benefits, you should also learn about some of its drawbacks. The Java OOPs concepts require a lot of effort. Moreover, object oriented programming is slower than other programs. The size of OOPs is also bigger than others. 

You should also find out about the advantages and disadvantages of arrays in C, C++, and Java. 

Best Practices for OOP Concepts in Java

The goal of the OOPs concept in Java is to save time without compromising ease of use and security. Some of the best practices of object oriented programming to achieve that goal are as follows:

• DRY or Don’t Repeat Yourself is a primacy concept in Java. Therefore, you should never use two blocks of identical code in two different places. You must be using a single method for different applications.
• If you want the Java code to alter in the future, you should encapsulate it by making every method and variable private at the outset. You can increase access to “protected” with time, if necessary. But don’t make it too public. 
• Single responsibility is one of the best practices for Java OOPs concepts. It involves ensuring that a class has a single functionality. It ensures that the class can be used or extended on its own when new applications for it emerge. It will help eliminate coupling between multiple functionalities. 
• The open-closed design is one of the best practices for the OOPs concept in Java. You will have to close all classes and methods for modification but keep them open for extensions. It will ensure that tried and tested codes of Java OOPs concepts remain static. But they can be easily modified to complete new tasks when required.

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Conclusion

Object oriented programming languages have various benefits over other programming languages. For instance, it can encapsulate data and behavior, while other programming languages treat them as separate entities. OOP can reuse code and develop complex systems with the help of inheritance. Moreover, it is more flexible than procedural programming and enables changes to be made in the underlying data without altering the entire system.