In the past, 99% of people used the Oracle (previously SUN) version of Java for all their Java needs. As of January 2019, the license is changing on Oracle Java which makes it no longer free for commercial use as well as the end of updates for Java 8. This has led to many people looking at alternatives to Oracle. Java itself is open source, so it will always be free and there are several other organizations offering their own builds of Java. If you want support, it matters which provider you get Java from.
This page is a work in progress to track the non-Oracle JREs and how to use them. Please send pull requests to this page with any additional information you have as this is a changing landscape right now.
You can read more about Oracle's changes in this post:
Corretto is a build of OpenJDK maintained by Amazon. It is free and will have long term support. Initial tests show that Corretto 1.8 works with CommandBox and ACF 11.
OpenJDK is Oracle's free version of Java. it comes with a 6 month support window. CommandBox has received a fair amount of testing on OpenJDK and everything seems to work.
Zulu is free and offers long term support. Zulu provides supported builds of OpenJDK. Initial tests show that Corretto 1.8 works with CommandBox and ACF 11.
When running box.exe on Windows, the registry is used to determine the current versions of java that are installed. If you install a some non-Oracle JRE such as Corretto, you will not currently have the necessary registry entries created for box to find Java.
Oracle - No manual action needed
Azul - No manual action needed
OpenJDK - Manual creation of registry keys required
Corretto - Manual creation of registry keys required
You can manually create the needed keys by modifying and running the following registry entries. (Contributed by Jim Pickering)
The box binary on *nix uses your OS environment variables to locate Java. In the absence of an env var called JAVA_HOME, box will look for java in the default system path.
Oracle - No manual action needed
Azul - No manual action needed
OpenJDK - Manual creation of JAVA_HOME required
Corretto - Manual creation of JAVA_HOME required
To manually configure the JAVA_HOME env var on a *nix system, edit your /etc/profile file to have these lines. Adjust the path as necessary based on your installation.
And as always, on any operating system and with any JRE provider, you can override what version of java is used by creating a folder called JRE in the same directory as the box or box.exe binary that contains the JRE you wish CommandBox to use. This will bypass all registry and env var checks above.
For macOS users who have installed CommandBox via HomeBrew, the installer creates a box alias in /usr/local/bin/ which points to the box binary in the /usr/local/Cellar/commandbox/<version>/bin/ directory. If you want CommandBox to use a particular version of the JRE then put the jre folder in the /usr/local/bin/ directory. If you want CommandBox to have a different home .CommandBox directory, place your commandbox.properties file in the /usr/local/Cellar/commandbox/<version>/bin/libexec/bin/ directory.
If you want to debug what JRE is being used by the CommandBox CLI, use the -clidebug flag when starting CommandBox and the first few lines will tell you what version of Java is being used, and where on disk it lives.
