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|Java - Interview Questions and Answers|
|Ans. There are four main OOP concepts in Java. These are:|
Abstraction. Abstraction means using simple things to represent complexity. We all know how to turn the TV on, but we don?t need to know how it works in order to enjoy it. In Java, abstraction means simple things like objects, classes, and variables represent more complex underlying code and data. This is important because it lets avoid repeating the same work multiple times.
Encapsulation. This is the practice of keeping fields within a class private, then providing access to them via public methods. It?s a protective barrier that keeps the data and code safe within the class itself. This way, we can re-use objects like code components or variables without allowing open access to the data system-wide.
Inheritance. This is a special feature of Object Oriented Programming in Java. It lets programmers create new classes that share some of the attributes of existing classes. This lets us build on previous work without reinventing the wheel.
Polymorphism. This Java OOP concept lets programmers use the same word to mean different things in different contexts. One form of polymorphism in Java is method overloading. That?s when different meanings are implied by the code itself. The other form is method overriding. That?s when the different meanings are implied by the values of the supplied variables. See more on this below.
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|What are the difference between composition and inheritance in Java?|
|What is the difference between Encapsulation and Abstraction?|
|What are points to consider in terms of access modifier when we are overriding any method?|
| Explain OOPs |
Explain OOPs Principles
Explain OOPs Concepts
Explain OOPs features
Tell me something about OOPs
|What is Polymorphism in Java ?|
|Why every object constructor automatically call super() in Object before its own constructors?|
|Can you give a real world example of Encapsulation and Abstraction ?|
|Difference between Overloading and Overriding ?|
|Difference between Composition and Inheritance ?|
|How compiler handles the exceptions in overriding ?|