Jim Driscoll

I've been neglecting my blog, but just a quick note to mention that my latest talk at JavaOne, DSLs with Groovy, is posted up on Slideshare. The talk's designed for someone with no significant Groovy experience (unlike most Groovy DSL talks), so if it's interesting to you, check it out. I'm hoping (but not promising) to turn the talk into a series of Blog entries in the coming weeks. So if you want, just wait, and I'll send you explanations in more digestible bits and pieces in the coming weeks. (As usual, this entry is cross posted to my main blog site.) ... (more)

Executing Groovy Programs in-memory

Now that we've gone over some Groovy basics, it's time to switch back to writing in the Java language, and talk about how to run Groovy programs inside your Java programs.  Like most general purpose programming languages, there's more than one way to do things in Groovy, and that's never more true when it comes to executing Scripts - I once counted 7 ways to use the String "System.exit(0)" to shut down the VM, and I'm quite sure that I missed a few.  For this example, we'll use the method I consider to be the best and most extensible, which uses the class GroovyShell. Before we ... (more)

A Quick Introduction to the Groovy Language (Part 1)

Before I start talking about using Groovy's capabilities to create a DSL (mostly in Java), let's take a few minutes to go over what Groovy is. Groovy is a general purpose scripting language which runs on the JVM, and can largely be viewed as a superset of Java.  Take the following program: public class Hello { String name; public void sayHello() { System.out.println("Hello "+getName()+"!"); } public void setName(String name) { this.name = name; } public String getName() { return name; } public static void main(String[] args) { Hello hello = new Hello(); hello.setName("world"); hel... (more)

A quick introduction to the Groovy language (part 2)

In my previous post, I started with a simple Java program (which also worked in Groovy), and slowly stripped out the cruft until I was left with the following Groovy script: def sayHello(name) { println("Hello $name!") } def name = 'world' sayHello(name) Now, let's add a little change to use an array.  Since Groovy is a rough superset of Java, you might be tempted to do something like: def sayHello(name) { println("Hello $name!") } String[] names = {"SintSi", "Kaitlyn", "Keira"} for (String name : names) { sayHello(name) } But this won't work.  This is one place where Java syntax d... (more)

Bridging to Open Ajax

The Open Ajax Alliance is a standards organization with the mission of ensuring interoperability within Web based Ajaxified applications. One of their standards relates to intercomponent communication - the ability to subscribe and publish messages which can then be picked up by code written by other authors. Please note that if you don't have an interest in Open Ajax, this post may not be especially illuminating - I've talked about the addOnEvent function before, even recently. To write an Open Ajax application, you need to subscribe to events, much like in JSF 2, by register... (more)