How to Crack Java Programming Interviews in 2024? Topics, Courses, Books, and Qu...

How to Crack Java Programming Interviews in 2024? Topics, Courses, Books, and Questions

Java Interviews are a little bit different than traditional programming interviews on tech giants and product-based companies like Google, Amazon, Microsoft, or Facebook. First, even though it has questions from Data Structures and Algorithms like String or Array, you can still manage to clear Java interviews if you are not an expert on them. The questions are a little bit easier and more practical than those companies. Another essential thing about Java interviews are questions based upon Java programming language and JDK API. Since Java is also an Object-oriented programming language, you will find lots of OOP questions there.

Loaded: 0.70%

Since Java is primarily used as an application programming language, the focus is aligned accordingly with questions mostly focusing on API, Java concepts, and design patterns.

Also, Java interviews change a lot depending upon the candidate's experience. For example, junior developers with 1 to 2 or 3 to 4 years of experience will see more questions on topics like Java fundamentals, API, data structure, and algorithms.

More senior developers like Java programmers with 5 to 6 years of experience will find more questions on concurrent programming, Java concurrency API, JVM internals, GC tuning, and Java Performance.

So your preparation should be aligned with your experience and not just focused on common programming questions.

Also, Java EE interviews are totally different than core Java interviews because core Java interviews are mostly focused on core Java concepts like Concurrency, Collections, and JVM internals, while Java EE interviews are based upon a framework like JSF, Spring, Hibernate, and others.

The best way to prepare for Java interviews is to join a course like Java Interview Guide: 200+ Interview Questions and Answers, though there is no substitute for the experience you can still manage to sail through by carefully preparing for your Java interviews.

Which Topics to Prepare for Java Interviews in 2024?

As I told you, the importance of topics depends upon the candidate's experience. I would ask more questions from Java fundamentals like String, Collections, equals() and hashcode and OOP concept to a fresher or Junior Java developers of 2 years experience, but those topics will be too trivial for Java developer of 4 to 5 years experience.

For those, I prefer to ask Concurrency, JVM internals, Garbage Collection, testing, and design patterns. Another thing that decides which topic you should prepare for your interview is the Job description.

Also, there is no better guide than the Job description to prepare for relevant topics.

For example, if you are going to work for a core Java multi-threading based application, then you should prepare well for core Java topics like multithreading and concurrency, Java Collections, Generics, Enum, GC Algorithms, and JVM internals.

Similarly, if you are going to work for a Java Web Service application then preparing about REST and SOAP, XML, JSON, and other relevant topics.

For Java, web application developers, JSP, Servlet, Spring, and Hibernate are more critical than multi-threading and JVM internals. Similarly, for an Android developer, apart from knowledge of Java fundamentals, knowing Android API is more important.

Nevertheless, here is the list of topics I suggest to any Java developer who is serious about interviews.

• Java Fundamentals
• Object-Oriented Concepts (questions)
• Data Structure and Algorithms (questions)
• Multithreading, concurrency, and thread basics (questions)
• Date type conversion and fundamentals (questions)
• Garbage Collection (questions)
• Java Collections Framework (questions)
• Array (questions)
• String (questions)
• GOF Design Patterns (questions)
• SOLID design principles (questions)
• Abstract class and interface (questions)
• Java basics e.g. equal and hashcode (questions)
• Generics and Enum (questions)
• Java IO and NIO (questions)
• Common Networking protocols
• Data structure and algorithm in Java (questions)
• Regular expressions
• JVM internals (questions)
• Java Best Practices
• JDBC  (questions)
• Date, Time, and Calendar (questions)
• XML Processing in Java (questions)
• JUnit 
• Programming questions (questions)

Apart from these topics, you could also take help from books like Java interview exposed and the Cracking the coding interview. These are great books written, especially from the interview perspective, and it will give you a good idea of what to expect in Java programming job interviews.

You will also find questions asked from various tech companies like Facebook, Google, and Investment banks like Barclays, Citi, Deutsche Bank, Morgan Stanley, and others.

For a more serious developer who wants to become an expert and not just focus on clearing an interview, I suggest you take a look at my 12 advanced Java books for experienced programmers article. It contains books for every important topic in Java.

And if you lack on some topic, you can always go back to the book you read or the course you followed to learn the Java-like The Complete Java MasterClass course on Udemy is a very comprehensive course and best for learning from scratch.

New Courses and Books For Java Interviews in 2024

Recently I come across some excellent books to prepare for core Java and web developer interviews, these books focus more on core Java concepts like multi-threading, collections, Java fundamentals, etc., but also touch on web development concepts like Web service, Spring, Hibernate, JSP, Servlet, etc.

These books and courses are both cheap, will cost you less than $15 but gives you enough practice and ideas to do well on your Java interviews.

Though nothing can beat the true experience and constant learning, if you are short of experience and not in touch with Java for more than a year, then you can use these books to prepare better for your Java interviews.

1. Java Interview Guide: 200+ Interview Questions and Answers

This is an excellent course to get an idea about Java interviews. It is very well organized and covers almost all the topics we have discussed here and probably more, e.g., web services, spring, hibernate, JDBC, etc. It is equally useful for both entry-level Java programmer and experienced Java developer interviews.

2. Grokking the Java and Spring Boot Interview