It's been more than a couple of years or so since JDK 9 was launched, and the new year is probably the best time to learn Java 9 and get yourself familiar with new features and enhancements on existing APIs. The highlight of the JDK 9 release was Project Jigsaw or Module system. The Java 9 Platform Module System allows Java to move forward by modularizing the JDK as well as adding modules as first-class citizens to Java, but that's not the only thing to look forward to, there are many small changes that are very useful in day-to-day coding. For me the static factory methods introduced in List, Set, and Map to create an immutable list, set and the map is the most interesting one. Along with several changes in Stream API and Optional class. Those are the ones, I will most likely use as soon as we start with JDK 9. If you are a regular reader of this blog, then you would notice that I haven't published an article on JDK 9 here yet, but I have been learning and doing some research in the last couple of days, and this article is the result of that. Also, when Java 8 was released, I had published a list of the best Java 8 tutorials, which many of my readers have appreciated, and I thought the same this time as well. In this article, I am going to share some of the interesting articles, tutorials, and online courses that you can use to learn Java 9. These are some of the best resources on JDK 9 at the moment. They are excellent to start with and get yourself familiar with. For more deep dive and in-depth knowledge, I suggest picking a good book on Java 9 or joining a course like What's New in Java 9 - Modules and more is a better option. 5 Best Java Module Tutorials and Courses Anyway, without further Ado, here is the list of useful tutorials to learn JDK 9 features, including modules, factory methods, and others. Table of Contents 1. What's New in Java 9 - Modules and More! [Udemy]This is one of the best course materials to learn Java 9 at the moment. You will not only learn about the Installation and Setup of JDK 9 but also all-important Java 9 features like The Java Shell (REPL) The Java 9 Platform Module System The Streams API Private Method in Interfaces Factory Methods for Collections Try With Resources Diamond Operator SafeVarargs AnnotationIt also covers updates to the Process API, which now allows Java developers to work with native processes directly in Java code. In short, one of the best resources to learn Java 9 in a quick time. This course is created by Tim Buchalka, author of Udemy's most popular Java course, The Java Programming Masterclass, covering Java 11 & Java 17, which is trusted by more than 600K developers. This means you will be learning from the master himself. 2. 9 New Features in Java 9 [Pluralsight] This is another good list of essential JDK 9 features on the Pluralsight blog by Sander Make, author of Java 9 Modularity: First Look course on PluralSight. In this article, Sander has gone through 9 of the essential JDK 9 feature, which matters most for Java developers. I particularly liked his example of The Java Platform module system and how modules are linked together in modularized JDK. The list also covers JShell: the interactive Java REPL, Improved Javadoc, Collection factory methods, Stream API improvements, Private interface methods, HTTP/2, and Multi-release JARs. By the way, you would need a Pluralsight membership to join this course which costs around $29 per month or $199 per year (33% discount). I highly recommend this subscription to all programmers as it provides instant access to more than 7000+ online courses to learn any tech skill. Alternatively, you can also use their 10-day-free-pass to watch this course for FREE. 3. Code First Java 9 Module System Tutorial Project Jigsaw or Module system was one of the highlights of the JDK 9 release, and this is probably the best course to start with that. The writer is also the author of The Java 9 Module System book, which means you will get a comprehensive overview of authority. In this tutorial, you will first learn a simple Hello World example and learn how to take an existing demo application and modularize it with Java 9. You will also learn how to create module declarations ( module-info.java) and use the module path to compile, package, and run the application. If you want to learn more, Joshua Bloch has also provided an excellent overview of JDK 9's Module system on Item 51 of Effective Java 3rd Edition, one of the must-read books for Java programmers in 2025. 4. First steps with Java 9 and Project Jigsaw This is another great tutorial to learn Project Jigsaw or JDK 9 Module system. It's a two-part tutorial, in the first part you will learn about what is a module and how the Java Runtime was modularized with a demo application that demonstrated how to (and not to) compile, package, and run a modular application. In the second part, he explains how does Jigsaw interoperates with non-modular legacy code and how you can build your own Java runtime images. In short, very comprehensive coverage of the Java 9 Module system with some hands-on advice on how to compile, build and run a modular application in Java 9. 5. Nine New Developer Features in JDK 9This is one of the first articles I read to learn about Java 9 features. The article explains two of my favorite features, Factory Methods for Collections (JEP 269) and Stream API Enhancements. If you are interested in those two, then you can read more about that article. Also, this is actually excerpted from the July/August 2017 issue of Java Magazine. So if you want to learn all 9 features, make sure you read the full article in Java Magazine. You can find the link at the bottom of that article. 6. Java 9 New Features on Baeldung The Baeldung blog also has an excellent overview of most of the useful Java 9 features. It's not comprehensive but provides an excellent overview of what every Java developer should know about Java 9 changes. It includes both significant changes like Project Jigsaw or Module system and Http 2.0 client but also smaller language enhancements like Diamond Operator Extension, which provides methods on an interface, Try-with-resource enhancements, and new API enhancements like changes on Optional and Stream API. It also covers Jshell. In short, if you need a quick overview of JDK 9 features, then this is a great list to start with. If you need a more comprehensive overview, I suggest joining What's New in Java 9 - Modules and more courses on Udemy. 7. Java 9 Features with Examples on JournalDev This is another good list of JDK 9 features with small examples. It includes most of the JDK 9 changes at the language and API level along with Module Systems and Factory method enhancements. Here is a full list of features which is covered in this article: Java 9 REPL (JShell) Factory Methods for Immutable List, Set, Map, and Map.Entry Private methods in Interfaces Java 9 Module System Process API Improvements Try With Resources Improvement CompletableFuture API Improvements Reactive Streams Diamond Operator for Anonymous Inner Class Optional Class Improvements Stream API Improvements Enhanced @Deprecated annotation HTTP 2 Client Мulti-Resolution Image API Miscellaneous Java 9 Features I really like their short descriptions and short examples. The list is pretty much similar to the previous list, and you can refer to it if you need a quick overview. If you need to learn each feature in-depth then you better join this Java 9 course on Udemy, you may get this course for just $9.99 on Udemy's flash sale. That's all about some of the best tutorials and courses to learn Java 9 features. The work on JDK 10 is already started, but like me, there are many Java developers out there who are still going through JDK 8 features. I don't know if I am going to use the module system anytime soon, but I am sure I'll use the API enchantments, like factory methods for creating an immutable List, Set, and Map as well as some Stream API enchantments as soon as we move to Java 9. Other Free Programming Resources you may like to explore The 2025 Java Developer RoadMap 10 Things Java Developers Should Learn in 2025 10 Essential Testing Tools for Java Programmers 20 Vital libraries in Java Developers 20 Books Java Programmers Can Read in 2025 10 Everyday tools for Java Programmers 5 Free Courses to Learn Spring and Spring Boot Online 10 Frameworks for Java and Web Developers 10 tips to become a better Java developer Top 5 Spring Boot Features Every Java developer should learn 10 Courses to learn Spring Boot in 2025 Thanks for reading this article so far. If you like these best Java 9 and Module tutorials, then please share them with your friends and colleagues. If you have any questions or feedback, then please drop a note. P. S. - If you are looking for online courses to learn Java from scratch, and not just Java 9 features then I suggest you join The Complete Java Programming Masterclass course by Tim Buchalka on Udemy. One of the most comprehensive and up-to-date courses to learn Java.