Polymorphism is the ability of a class instance to behave as if it were an instance of another class in its inheritance tree, most often one of its ancestor classes. Overriding is the means by which you achieve polymorphism. Java Polymorphism vs Overriding vs Overloading explained in detail to handle drill down Java OOP interview questions with ease when quizzed further.
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Q18. Given code:
A18. Firstly, let’s take abstraction and encapsulation as the difference is subtle. Abstraction is often not possible without encapsulation because if a class exposes its internal state, it can’t change its inner workings.
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A software application is built by coupling various classes, modules, and components. Without coupling, you can’t build a software system. But, the software applications are always subject to changes and enhancements. So, you need to build your applications such a way that they can not only adapt to growing requirements,...
Design principles interview questions & answers for Java developers so that you can expand your OOP skills to design robust Java apps Q25. What are the SOLID design principles? A25. SOLID is an abbreviation for 5 design principles. SRP (Single Responsibility Principle) If you have a class with calculation logic,...
Tip #1: Tightly encapsulate your classes. A class generally contains data as well as methods, and is responsible for the integrity of its own data. The standard way to protect the data is to make it private, so that no other class can get direct access to it, … Read more...
A trivial coding example (i.e. a Calculator) tackled using the following programming paradigms in Java not only to perform well in coding interviews, but also to learn these programming paradigms.
Approach 1: Procedural Programming
Approaches 2 – 4: Object Oriented Programming
Approach 5: Functional Programming (Java 8)
Approach 1: Procedural
Output: result=13
Approach 2: OOP
When you have more mathematical operations,
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If you don’t get Java OOPs interview questions & answers right in the job interviews you can say OOPS !!!! to your Java interview success. Q1. Is Java a 100% Object Oriented (OO) language? if yes why? and if no, why not? A1. … Read more ›...
Q. Is there anything wrong with the following class design? If yes, can the design be improved? JUnit test class. A. It’s not a good idea to try to anticipate changes in requirements ahead of time, … Read more ›...
We have already looked at Why favor composition over inheritance? with reasoning and code examples. Inheritance still has its use and let’s look at some real life examples. #1. Unit Test Classes In the base class you can wire up Spring configs, shared logic, … Read more ›...
This is not only one of the most popular Java OOP Interview Questions & Answers asked 90% of the time in job interviews, but also a key OOP concept you must know well. The correct answer depends on the problem you are trying to solve, and the answer you give reveal a lot about your know-hows &
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