Java 17 has been in production since September 2021 – and many teams still aren’t using the new features. Records, Sealed Classes, Pattern Matching: these language features make code easier to understand and maintain.
In two days, this course brings your team up to the level Java 17 makes possible – clearly explained and immediately applicable.
In this two-day course, you’ll learn and master all major new features introduced in Java versions 12 through 17 – in-depth, easy to understand, and with a strong focus on real-world projects.
We’ll explore how modern language features like Records, Switch Expressions, and Pattern Matching make your code more elegant and maintainable. You’ll learn how Text Blocks simplify working with multi-line strings – and how numerous smaller enhancements to the standard API can save you time.
You’ll also get an overview of ZGC and Shenandoah, production-ready since Java 15 – and how the existing garbage collectors have been improved.
You’ll also learn what to watch out for when upgrading to Java 17 – in particular, why Strongly Encapsulate JDK Internals becomes a stumbling block for many teams and how to solve it with confidence.
With hands-on exercises – often based on real project scenarios – you’ll immediately apply what you’ve learned and reinforce your understanding.
At the end of the course, you’ll also get a preview of upcoming features – for example, Pattern Matching for switch, introduced as a preview in Java 17.
You’ll find a complete overview of all new features in the Java 17 features article.
This course is designed for Java developers who want to stay up to date – practical, hands-on, and full of “aha” moments. Ideally, participants should have at least two years of professional Java experience.
The course is also ideal for teams already using Java 17 who want to deepen or refresh their knowledge.
For engineering leads and teams who want to upgrade to Java 17 or get their team ready for the next LTS version, this course is the right starting point.
If you want to catch up on Java 17 and 21 in one go, the combined Java 17 + 21 course is the right choice – or cover all three LTS versions in the combined Java 17 + 21 + 25 course.
We won’t follow the listed order strictly. Instead, we’ll alternate between major features, smaller topics, and theory – keeping the course engaging and balanced, and helping you better retain the material.
Major Features:
switch ExpressionsinstanceofAdditional Enhancements:
NullPointerExceptionsAPI Improvements:
String methodsStream methodsFiles.mismatch()ByteBuffer methodsInstantSourceGarbage Collection:
Performance:
TreeMap implementationsTools:
Deprecations & Removals:
Thread.suspend() and resume(): deprecated for removalThreadGroup: stop(), destroy(), isDestroyed(), setDaemon(), and isDaemon()Looking Ahead:
switchThe agenda isn’t set in stone: we can align the focus, date, and format with your team.
Request now – no obligationI’ve been working with Java for 30 years – as a developer, CTO, trainer, and speaker – and have helped teams modernize complex Java systems and make them more performant.
With HappyCoders.eu, I’ve built one of the most widely read Java blogs in the German-speaking world.
My articles on Java upgrades in Java Magazin and my talks, e.g. at JavaLand, show: I know the pitfalls from practice – not just in theory.
My goal: to make complex topics understandable, practical, and immediately applicable.
100 % of the participants who answered would recommend my training – 82 % without reservation.
More about meSven Woltmann of HappyCoders visited us to test and understand the new features around Java 25 together.
For two days, we worked intensively on Unnamed Variables & Patterns, Stream Gatherers, Scoped Values, the Foreign Function & Memory API, and performance topics such as virtual threads without pinning.
A big thank you to Sven for the excellent preparation, the clear didactics, and the deep technical expertise. That was a training exactly to our taste.
Content and presentation nearly flawless. I enjoyed listening throughout, learned new things, and had fun doing it.
Your confidence in answering questions along the way was impressive.
I found the trainer easy to listen to, and it never got boring. I understood the explanations well. Sven answered questions quickly and corrected errors in the worksheets on the spot.
A comprehensive training, with a trainer who knows what he is talking about. And when he doesn’t know, he looks it up right away or follows up with the answer shortly after.
Anyone who understands Java can easily follow this training. The exercises are well thought out and focused on the essentials.
A knowledgeable trainer. Good structure, practical examples. Compact, and the concepts get explained. Good, comprehensible exercises.
The overall package was very coherent and always tailored to us.
A good, in-depth overview of all relevant Java features since Java 8, and the opportunity to try all of these features out yourself.
The talk was broken up by fitting exercises. Good presentation. Our questions were taken up.
Very practical and good exercise examples.
Quick to respond to questions – a very flexible trainer.
A compact overview of how Java has evolved. A lot of input, much of which you can apply directly.
Very good repo with explanations + exercises in one place.
Pace + depth: top-notch. A very pleasant mix of theory and practice.
A complex topic broken down superbly.
All the important news from Java 9–25 was well explained.
This training can only be booked for teams. If you’d like to attend as an individual, I offer two courses (in German) through ppedv:
Both are possible: I can come to your company for an on-site training – anywhere in Germany, Austria, and Switzerland – or we run the training online, usually via Zoom.
I recommend a maximum of 12 participants per training – that way I can give everyone individual attention. There is no minimum: I charge per training, not per person.
The easiest way is the request form or an email to training@happycoders.eu. Right after submitting, you can book a video call via Calendly, where we discuss the details. You’ll then receive a concrete offer from me.
Ideally, you’re familiar with Java 11. If you’ve worked with Java 8, you’ll be fine too – the most important differences are put into context during the course. In general, I recommend at least two years of practical Java experience.
All participants need an up-to-date IDE with at least Java 17 – I use IntelliJ IDEA myself. Java 17 or later should also be installed in the terminal, as we’ll run some of the exercises there.
A training day consists of four 90-minute modules – six hours of net training time in total. Each module alternates between theory and practice two to three times, so you apply what you’ve just learned directly to code. There’s a short break between the first and second and between the third and fourth module, and a longer lunch break between modules two and three. We align the exact schedule with your working hours – that’s flexible.
About half theory, half practice: a short theory phase is followed directly by applying it to code – with examples from real projects. Listening alone doesn’t help much; the knowledge has to be used immediately for it to stick.
Yes – shortening topics, weighting them differently, changing the order, or combining content from different courses: I’m happy to adapt the agenda to your team. Since that means reworking the training materials, it involves extra effort – I’ll prepare an individual offer for you.
We usually use Zoom. If you prefer your own platform – for example, Microsoft Teams or Google Meet – I’m happy to work with that. Just let me know in advance.
Yes. Before the training, you’ll receive the exercises as a Git repository so you can get started right away. After the training, you’ll also receive the slides – including all solutions to the exercises.
Yes. All participants receive a certificate of attendance after the training.
Travel expenses are charged as a flat rate – depending on the training location and the number of overnight stays required. The exact amount is part of the individual offer I’ll send you.
Yes. For multiple booked trainings or follow-up bookings, I can offer a volume discount. We’ll discuss this in the video call, and I’ll include it in the offer.
Just write to me – I usually reply within one business day.
Or book a free video call right away, and we’ll discuss everything important.