Categories: FreshersJava

Java Interview Questions (Part 1) – Rookies Series

The article (first in the series) aims to present some tricky interview Java questions that could help you score high in your next Java interviews:

  

Programming fundamentals

  

Java Objects

  

Collections
  • Question: What is difference between LinkedList and ArrayList? When would you want to use one and not the other?
    Answer: http://javarevisited.blogspot.in/2012/02/difference-between-linkedlist-vs.html
  • Question: How come you keep on adding objects in an ArrayList using add method and no exception is ever thrown? Could you think about underlying code?
    Answer: Take a look at the pictures below. The magic happens in the ensureCapacity method where a new arrayList is created, the elements from old arraylist is copied to new one and reference of new arraylist is assigned to member variable (elementData).

    fig: java arraylist add method

  • Question: What is difference between a Set and a List?
    Answer: The primary difference is that Set is a collection that consists of no duplicate elements or, in other words, consists of all unique elements.  Read further on the following page:
    http://stackoverflow.com/questions/1035008/what-is-the-difference-between-set-and-list

  

Exception Handling

  

Others

 

[adsenseyu1]
Ajitesh Kumar

I have been recently working in the area of Data analytics including Data Science and Machine Learning / Deep Learning. I am also passionate about different technologies including programming languages such as Java/JEE, Javascript, Python, R, Julia, etc, and technologies such as Blockchain, mobile computing, cloud-native technologies, application security, cloud computing platforms, big data, etc. I would love to connect with you on Linkedin. Check out my latest book titled as First Principles Thinking: Building winning products using first principles thinking.

View Comments

Recent Posts

Mathematics Topics for Machine Learning Beginners

In this blog, you would get to know the essential mathematical topics you need to…

2 weeks ago

Questions to Ask When Thinking Like a Product Leader

This blog represents a list of questions you can ask when thinking like a product…

2 weeks ago

Three Approaches to Creating AI Agents: Code Examples

AI agents are autonomous systems combining three core components: a reasoning engine (powered by LLM),…

3 weeks ago

What is Embodied AI? Explained with Examples

Artificial Intelligence (AI) has evolved significantly, from its early days of symbolic reasoning to the…

2 months ago

Retrieval Augmented Generation (RAG) & LLM: Examples

Last updated: 25th Jan, 2025 Have you ever wondered how to seamlessly integrate the vast…

5 months ago

How to Setup MEAN App with LangChain.js

Hey there! As I venture into building agentic MEAN apps with LangChain.js, I wanted to…

5 months ago