Top 21 final modifier (keyword) Interview Questions and Answers in Java

The final modifier is one of the important keywords in Java. You can use this with a class, method, and variable as well. Good knowledge of the final keyword is not only essential for writing good, performant, and secure Java programs but also to clear any  Java interview. The interviewer pays special attention to the final keyword and expects candidates to know how and when to use the final modifier with variables, methods, and classes. In this article, I have collected Java interview questions that are based upon the concept of the final modifier. You might have seen many of these questions on both telephonic and face-to-face rounds. 

Is it possible to have an abstract method in a final class? Example

This is one of the interesting core Java questions which was asked to one of my readers recently during a telephonic interview for a Java developer job interview. Even though he knows that you cannot make an abstract class final in Java, he got confused by the wording of the methods. The answer is simple, No, it's not possible to have an abstract method in a final class in Java. Why? because as soon as you declare an abstract method in a Java class, the class automatically becomes an abstract class and you cannot make an abstract class final in Java as discussed before, hence it's not possible to have an abstract method in a final class in Java.

What is final in Java? Final variable , Method and Class Example

Final in Java is very important keyword and can be applied to class, method, and variables in Java. In this java final tutorial we will see what is a final keyword in Java, what does it mean by making final variable, final method and final class in java and what are primary benefits of using final keywords in Java and finally some examples of final in Java. Final is often used along with static keyword in Java to make static final constant and you will see how final in Java can increase the performance of Java application.