This appendix will serve as a reference when using pure JRuby features. All these features (except for the JRuby module) are only available after executing this:
This happens automatically if you reference the module named
Java, though. Chapter 6 also covers the information in this appendix, with much more information and detail, when that is needed.
It's easy to use Java classes and interfaces from JRuby, as we've seen through the book.
To reference a Java class in the
org packages, you can use top-level references:
com.foo.Bar java.util.HashMap org.jruby.Main
When working with a class in another package, use the ...