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00: Why favor composition over inheritance?

This not only one of the most popular Java OOP Interview Questions & Answers asked 90% of the time in job interview, but also a key OOP concept you must know …


03: Q16 – Q17 Java Polymorphism vs Overriding vs Overloading

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…


04: Q18 Explain abstraction, encapsulation, Inheritance, and polymorphism with the given Java code?

Q18. Given code:

…

05: Q19- Q24 How to create a well designed Java application with OOP?

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. …


06: Q25 – Q32 Design principles interview questions & answers for Java developers

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 …


07: Q33 Top 5 OOP tips for Java developers

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 …


08: Write code to add, subtract, multiply, and divide given numbers?

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 …


Q1 – Q10 Java OOPs interview Q&As

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 …


Understanding Open/Closed Principle (OCP) from the SOLID OO principles with a Java example

Q. Is there anything wrong with the following class design? If yes, can the design be improved?

…

What are good real life Java inheritance (or use of abstract classes) examples ?

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 …


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