Appendix A
JDK 11 was released on September 25, 2018. Aside from all the novelties already covered in this book, there was also the news that developers had been suspecting since the introduction of modules. Java is still free, but the Oracle JDK isn’t. Developers can use the Oracle JDK to learn, but applications that are deployed in production require a license.
The work-around is to use an OpenJDK build (https://adoptopenjdk.net), but this does not come with Oracle support. JDK 17 is a major release that will benefit from long-term support and if you are curious about the Oracle terms of use, you can read them at https://www.oracle.com/technetwork/java/javase/terms/license/javase-license.html.
The Java world has changed, and Oracle restrictions ...