Groovy, the Red Pill: Metaprogramming--How to Blow the Mind of Developers on the Java Platform
TS-5572

This session undoes the past year's hard work of convincing conservative Java platform shops that there's nothing radical about Groovy. OK, it is still true that you can Groovy-enable your Java technology-based application by adding a single Java Archive (JAR) to the classpath. It is still true that Groovy can mix in seamlessly with your legacy Java technology-based application, because at the end of the day, Groovy is implemented on the Java platform. It is still true that you can use your existing Java IDE to write Groovy, use your existing build process, and deploy to your existing platform the same old way you always have. But what fun is that?

The presentation focuses on the ways Groovy can turn the world view of a traditional developer on the Java platform upside down. It starts by talking about how you can thumb your nose at The Man by leaving out many of the main syntactic hallmarks of the Java programming language: semicolons, parentheses, return statements, type declarations (a.k.a. Duck-typing), and the ever-present try/catch block. Then it looks at features such as operator overloading and method pointers that Groovy welcomes back into the language with open arms.

But the bulk of the session focuses on metaprogramming with Groovy. The presentation adds new methods to classes at runtime--even if they were originally implemented on the Java platform and even if they were declared final. (Thanks, ExpandoMetaClass!) It calls methods that don't exist and avoids the dreaded MethodNotFound Exception. (Thanks, invokeMethod!) It narrowly scopes metaprogramming shenanigans with use blocks and categories and then casts the changes to the wind so that every instance of a class gets the added juice.

If you are happy taking the Blue Pill, this session is not for you. You can continue using Groovy as a slimmed-down dialect of the Java programming language--an "After" picture to the Java programming language's "Before." If, however, the Red Pill looks interesting, please attend this session. Remember, all it is offering is the truth. Nothing more.

Who should attend? This session is aimed squarely at developers on the Java platform. The more experience you have, the better, but even neophytes will appreciate what Groovy offers developers on the Java platform. Experience with other dynamic languages such as Ruby, the JavaScript programming language, or Python will help but certainly isn't required.

What should you know before attending? You should be comfortable with the basic syntactic rules of the Java programming language (so they can be mercilessly squashed). You should understand the basic "Laws of the Java Programming Language" when it comes to the semantics of a statically typed language (so sand can be kicked in its face). Most important, you should possess an open mind and a belly full of dynamic-language KoolAid. This is not the forum for someone who wants to vocally defend the merits of checked exceptions and static typing. You will be unceremoniously tossed out on your ear, Jerry Springer-style. Seriously. The presentation doesn't try to convince you that this is the way you should write Java code. The status quo can defend itself quite nicely, thank you very much. The session aims to show you how your code could look if you so desire.

Watch The Session
You need to be a registered Sun Developer Network member to view this multimedia session. If you are a registered SDN member, please click on "Watch Multimedia" button to log-in to view the multimedia session. If you wish to join SDN, please click here.