Groovy is a long way towards this goal. Although it doesn’t have perfect Java compatibility, it does follow Java syntax pretty closely and you can generally guess what something will look like with the only new syntax being those things that are actually new features. Like closures and builders for instance. Like most good programming languages it borrows a lot from its peers, Python, Ruby, and Perl while leaving self, end, and $%*)&@#$@( behind. Although they are further along adoption and maturity-wise, Groovy comes fully equipped with a framework and class library that they will only dream about — the full Java platform. Not only can you use the frameworks, you can even implement interfaces and extend classes using Groovy so you are not in any way limited.
Not only is the feature set nice, I’ve had the pleasure of looking at the source code, fixing some bugs, and now adding some new things, like a GroovyServlet that will run your Groovy scripts directly from a web application. As a testament to their programming prowess, it only took about 100 lines to write it. Groovy’s internals boast extremely clean APIs and an obviousness that makes it a pleasure to work with. Additionally, since they develop in Eclipse, you can just check it out as a project or use Maven to build on the command-line.
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