10 Best Java Interview Courses for Beginners and Experienced Developers in 2025

Hello friends, if you are preparing for Java interviews like for a core Java developer role in a big Investment bank like JP Morgan, Morgan Stanley, etc., or a Java web developer in service-based companies like Infosys, TCS, Luxoft, Tech Mahindra, IBM, and Cognizant, and looking for some awesome courses and material, then you have come to the right place.

Earlier, I have shared the best coding interview books and courses, which focused on essential coding interview skills like Data Structure and Algorithms, SQL, Linux, etc.  

While those are still very good to prepare for any coding interview, including the Java developer role and you can use them to build your programming fundamentals.

In this article, I will share some of the best online courses you can take to prepare key topics like core Java, multithreading, concurrency, algorithms, data structure, system design, design patterns, and software architecture.  

These are advanced online interview preparation courses that focus on programming job interviews by sharing helpful questions and teaching you techniques to answer them. 

There is no order in which you want to prepare but I  think you can start with the topic you most struggle with, for example, many of my readers told me that they struggle to solve coding and system design problems during Java interviews.

In that case, you can start with the system design and coding pattern course mentioned in this article. 

Similarly, if you are in rush and don't have much time to prepare for your interview, it's better to join a book or course where you can quickly revise all concepts. In that case, you can read these Grokking the Java Interview and Spring Boot Interview books. You can also use code friends30 to get 30% discount.

10 Best Online Courses to Crack Java Interviews in 2025

Without wasting any more of your time, here is my list of 10 online courses to crack any Java Programming interviews. I have included courses to cover essential coding skills like Data Structure and Algorithms, Problem-solving, Core Java, Concurrency, Design Patterns, and Software Design, Object-oriented programming, SQL, and Spring Framework with Spring Boot.

1. Grokking the System Design Interview

Until long ago, System Design questions were normally not asked on Java interviews but things have changed in last few years. You will see an increase in System Design, Architecture and OOP Design questions on Java developer interviews along with classic Java, Multithreading, and Spring Boot questions.

System design is closely related to OOP design and analysis but focuses on the much bigger picture at component and tier level rather than class level.

To solve system design questions like designing a website like Amazon or designing a complex system handling millions of orders.

You need to know a lot of stuff to solve these problems, from caching to DB interaction, scaling to load-balancing, and how the distribution system works.

If you have never done this before, don't worry, this course will walk you through some common system design problems from companies like Amazon, Apple, Facebook, Microsoft, Google, IBM, etc., to give you enough knowledge and skills to crack system design question on your Interview.

Here is the link to join this course - Grokking the System Design Interview

Though, if you are preparing for coding interviews including Java developer interviews then I also recommend you to get all of DesignGurus.io courses which include Grokking the Coding Interview Pattern, Grokking the Dynamic Programming Pattern and Grokking the Advanced System Design pattern and several others.

You can actually get all courses as a bundle for a 70% discount, I highly recommend that for better preparation. 

And, if you need more choices you can also see this list of best system design courses for Java interviews. 

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

This is your one-stop shop for all kinds of traditional Java interview questions you can expect in companies.

It covers Java questions from telephonic round to face-to-face round and covers all essential topics like collections, generics, concurrency, core java, etc.

This is one of the most comprehensive courses for Java developer interviews as it covers almost all the core Java topics which a Java developer needs to prepare for interviews. 

If you need to buy just one course for your Java interview preparation, then you should buy this course. It is also very affordable. 

Here is the link to join this course - Java Interview Guide: 200+ Interview Questions and Answers

3. Grokking the Coding Interview: Patterns for Coding Questions

One of the most essential things to crack any programming job interview is your ability to apply whatever you have learned to a completely unknown problem.

This is very important because sometimes you will face questions which you have never heard before, and you need to solve them right there.

This course helps you to build those patterns in your mind. It will teach you some of the most useful techniques to apply to coding problems and break them down into a known pattern,

For example, you can use a Stack to convert a recursive solution to an iterative one.

You can divide a number by 10 to eliminate the last digit and take the remainder to get the last digit. Similarly, a stack is beneficial for parsing, etc.

In short, one of the best coding algorithm courses for Java developer interviews.

Here is the link to join this course - Grokking the Coding Interview: Patterns for Coding Questions

Btw, you would need an Educative subscription to join this course, which not only provide access to this course but more than 1200+ AI powered courses to learn essential tech skills, prepare for coding interview and improve yourself as a Developer.

If you want to invest yourself and upgrade your tech skill, this is one subscription you definitely need. They are also offering 50% discount now.

4. Grokking the Object-Oriented Design Interview

Another important topic in Java interviews is object-oriented analysis and design.

You will be either given a requirement like designing a vending machine or coffee machine and need to code in 2-hour or so with unit test, or you will be involved in verbal discussion.

If you have never done any object-oriented analysis and design, this is a great course to prepare for a Java interview and learn from real examples. 

Here is the link to join this course - Grokking the Object-Oriented Design Interview

And, if you need more options or alternatives then you can also see this list of best courses to prepare for Object-Oriented Programming and Design for Java interviews. 

5. Java Multithreading for Senior Engineering Interviews

Concurrency in Java is one of the most complex and advanced topics brought up during senior engineering interviews. Knowledge of concurrency and multithreading can put interviewees at a considerable advantage.

This course lays the foundations of advanced concurrency and multithreading and explains concepts such as Monitors and Deferred Callbacks in depth.

This skill can separate you from the crowd, and this course is great for building necessary concurrency skills.

You will practice some common concurrency problems from programming interviews and learn some key techniques and concepts like latch, barriers, synchronization, race conditions, etc. All the above four courses are from the Educative platform.

Here is the link to join this course - Java Multithreading for Senior Engineering Interviews

You have options either to buy these courses or go for the Educative subscription, which costs around $18 per month (45% discount) and gives you access to their 1200+ software development and coding courses.

I prefer the subscription because sometimes you just need that flexibility to join the course whenever you want without going into all the hassle of buying it.

6. 200+ SQL Interview Questions

SQL is another topic that is very common in Java interviews. Good knowledge of SQL and Database concepts like normalization and query optimization goes a long way in securing a job and working on a complex project. 

This course is good to prepare for an SQL Developer Interview with these 200+ real World SQL Questions and Practical Answers.

Here is the link to join this course - 200+ SQL Interview Questions

If you are new to SQL and Database, you can also check out these best SQL courses to build and revise some SQL and database fundamentals. 

7. Grokking Dynamic Programming Patterns for Coding Interviews

You might know that Dynamic Programming (DP) problems can be some of the most intimidating in a coding interview. 

Even when it's actually clear if a problem can be solved using DP (which it rarely is), it can be pretty challenging to even know where to start on the solution.

Unless that is, you're trained on the approach to solving DP problems.

This course is made from scratch with just that goal in mind. It'll equip you with a set of easy-to-understand techniques to handle any DP problem. 

Rather than just having you try to memorize solutions, you'll be walked through five underlying DP patterns that can then be applied to solve 35+ DP problems.

Here is the link to join this course - Grokking Dynamic Programming Patterns for Coding Interviews

If you need more choices, you can also see this list of best dynamic programming courses for coding interviews. 

8. Java Data Structures & Algorithms + LEETCODE Exercises

Along with SQL, Data Structure and Algorithms are two other skills that are very common in interviews.

In fact, those are so important that if you don't brush upon them, you will not go past the telephonic round in most interviews.

This course can be used to level up your Data structure and algorithms skills before  Java interviews.

Here is the link to join this course - Java Data Structures & Algorithms + LEETCODE Exercises

9. Design Patterns in Java

Design patterns are like concurrency, an essential skill for Java developers. It's expected from senior developers that they know about all object-oriented patterns and understand when to use them in your code. 

If you don't know about design patterns or GOF design patterns, then this course will help you to discover the modern implementation of design patterns in Java

Here is the link to join this course - Design Patterns in Java

And, if you need more choices, you can also see this list of a must-have design pattern course for senior Java developers.

10. Spring and Spring Boot Interview Guide

Spring and Spring Boot is probably the most important framework for Java developers. The interviewer expects you to know how to work on Spring and Spring Boot projects, and that's why there will always be some questions on this topic. 

This is a good course to prepare for Spring interview questions as you will learn to answer 200 interview questions on Spring, Spring Boot, and Spring MVC. 

Here is the link to join this course - Spring and Spring Boot Interview Guide

This course is a great resource for revising all those important Spring and Spring Boot topics before interviews.

Though, if you are in hurry. You can also combine this with, Grokking the Spring Boot Interview book. You can also use discount code friends20 to get 20% OFF. 

That's all about some of the best courses to crack your next Java interviews. These courses cover some of the most essential topics for any programming job interviews and are useful for core Java developers looking to get into big investment banks like Goldman Sachs, JP Morgan, Barclays, Citibank, Deutsche Bank, and others and Java web developers working on service-based companies like Infosys, TCS, Wipro, Cognizant, Tech Mahindra, and others.

Other Java Interview resources for you

• How to Prepare for Java Programming Interviews in 2025 (guide)
• 133 Java Interview Questions from the last 5 years (list)
• 15 Data Structure and Algorithm Interview Questions (list)
• 10 Spring Framework Interview Questions (list)
• 6 Courses to learn Spring Framework in-depth (courses)
• 20 Hibernate Framework Interview Questions with Answers (list)
• 50 Java Concurrency Interview Questions (list)
• 10 Courses to prepare for Coding Interviews (course)
• 25 Java Collection Interview Questions (list)
• 10 RESTful Web Service Interview Questions for Java developers (list)
• 10 Data Structure and Algorithms Courses for Interviews (courses)
• 50+ Data Structure and Algorithm Questions (questions)
• 20 Spring MVC Interview Questions for Java Developers  (questions)
• 20 Spring and REST Interview Questions for Java Programmers  (questions)
• 20+ Spring Boot Interview Questions with answers (questions)
• 10 Best System Design Courses for Coding interviews (best courses)

Thanks for reading this article so far. If you find these best online courses useful in your Java interview preparation, please share them with your friends and colleagues. IF you have any questions or feedback, then please drop a note.

P.S. - If you prefer books, then you can also check out my list of top ar System Design Interview  - An Insider's guide book and recently released Coding interview pattern book by Alex Xu, both are excellent.