As predicted, this week Google announced that its Google App Engine now supports Java. This was the first feature request put in when the cloud service was unveiled a year ago, so as you can imagine there’s a great deal of excitement in the air on this point. Here’s a round-up of the highlights: One thing last week’s speculation got wrong: The App Engine VM is not Dalvik’s, the Harmony-derived not-Sun-Certified VM that underlies the Android platform. The Java Performance Blog has the scoop — it’s just a standard Sun Java HotSpot Client VM. Google has a list of technologies that will work with App Engine. The service is open not just to Java, but to other JVM-based languages as well — JRuby, Groovy, Scala, Jython, and BeanShell. The Java EE spec is not entirely supported; Spring is supported, Hibernate and Struts are not. SpringSource is pretty excited about the Groovy and Spring angles, obviously, and even has a tutorial on writing a Groovy app for App Engine. Ola Bini had got a sneak peak at this, and offers his impressions. Over at O’Reilly, Hari Gottipati offers a pretty detailed breakdown of what you can expect. And as ZDNet reminds us, Java on App Engine isn’t just a boon for Java. It also brings the App Engine service more firmly into the mainstream. I hope you all enjoy playing with Google App Engine next week, while I’m off on vacation! Hopefully Sun won’t be acquired by the Sheinhardt Wig Corporation until I get back. Cloud Computing