java developer - Java Developer Interview Questions

Your Guide to the Top Java Developer Interview Questions

Despite being one of the oldest programming languages around, Java is still one of the most widely used in the industry. This means that the need for qualified Java Developers isn’t letting up.

To secure a Java Developer role, you’ll need to demonstrate your Java skills, knowledge and expertise during the interview process. The field is highly competitive, so in order to wow potential employers, you’ll be expected to show them exactly how well you know your stuff. 

If you want to ace your next interview, here are some ideas on how you can get prepared with these Java Developer interview questions. 

Getting Ready For Your Interview

While your Java Developer resume provides insight into your skills and experience, you’ll need to be able to articulate how these look in practical situations. In order to do this, you’ll need to have your terminology nailed down. 

Some common terms that you should be prepared to explain include:

  • Class
  • Object
  • Inheritance
  • Interface
  • Abstract class
  • String
  • Array
  • Factorial
  • Permutation

Foundational Java Developer Questions

The first type of Java Developer interview questions you can anticipate being asked are foundational questions. These are designed to test your knowledge and see just how well you know the key aspects of Java development. 

Some questions you may be asked include:

  • What’s Java?
  • How does Java support high performance?
  • Why’s Java a platform-independent language?
  • What are the key features of Java? 
  • What are the Java IDEs?
  • What’s a local variable? What is an instance variable?
  • How do you reverse a string in Java?
  • How do you find an intersection of two arrays?
  • How do you create deadlock between two threads?

Technical Application Questions

Not only will you be expected to explain your skills, but you can also expect to be asked to demonstrate them. As with just about any job in the industry, tech tests generally make up a portion of the Java Developer interview. 

Expect the technical portion of the interview to focus on functions required for the specific job you’re applying for. However, there are still some common Java Developer interview questions that you’ll likely run across during this part of the interview. 

These questions generally start with “Write a Java Program to…”. Some sample questions could be:

  • Find a square root of X number. 
  • Implement merge sort.
  • Implement a quick sort. 
  • Implement insertion sort.
  • Implement selection sort. 
  • Convert uppercase to lowercase.
  • Remove specific characters in a String.
  • Calculate the total number of characters in a String.

Advanced Tools

Not every Java Developer has the same suite of skills, and the tools they primarily use may vary. When you’re preparing with Java Developer interview questions and answers, it’s important to take a moment to consider what sort of tools you may be asked about. Interviewers will likely be looking not just for you to tell them you’re familiar with certain tools, but also how you’ve used them in the past.  

These could include:

  • Apache Spark
  • Kafka
  • Spring Security
  • Spring Boot 2
  • Spring Framework 5.0
  • Docker
  • Groovy
  • Git
  • Jenkins
  • Selenium 

Land Your Dream Java Developer Job 

By preparing to answer some of the Java Developer interview questions, you’ll be well-positioned to showcase your skills and along with showing why you should be paid a top Java Developer salary. Whether you’re seeking an in-person or remote Java Developer job, a strong interview will be the key to being the person to land the role. 

Are you interested in pursuing a new career as a Java Developer or up-leveling your current Java skills?

Udacity’s Java Programming and Java Developer Nanodegree Programs combine technical skills with hands-on practice that help prepare students to secure a career in the exciting and challenging world of Java. 

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