Part 3. Polyglot programming on the JVM

This part of the book is all about exploring new language paradigms and polyglot programming on the JVM.

The JVM is an amazing runtime environment—it provides not only performance and power, but also a surprising amount of flexibility to the programmer. In fact, the JVM is the gateway to exploring other languages beyond Java, and it allows you to try out some different approaches to programming.

If you’ve programmed only in Java, you may be wondering what you’ll gain from learning different languages. As we said in chapter 1, the essence of being a well-grounded Java developer is to have a growing mastery of all aspects of the Java language, platform, and ecosystem. That includes an appreciation of topics that are on the horizon now, but that will be an integral part of the landscape in the near future.

The future is already here—it’s just not evenly distributed.

William Gibson

It turns out that many of the new ideas that will be needed in the future are present in other JVM languages today, such as functional programming. By learning a new JVM language, you can steal a glimpse into another world—one that may resemble some of your future projects. Exploring an unfamiliar point of view can help you put your existing knowledge into a fresh light. This opens the possibility that by learning a new language you’ll discover new talents you didn’t know you had and add new skills that will prove useful going forward.