Java in the cloud: Google, Aptana, and Stax
Google App Engine, Aptana Cloud, and Stax for EC2 make it easy to spin up and scale a simple Java Servlet Container, but are still a far cry from the full Java EEFollow @infoworld
The service is just a pretty face on many of the standard VPS (virtual private server) tools out there, something that will be comforting and familiar to anyone with hard-won experience wrestling with the standard offerings. Access to the database is available on port 3306. Secure FTP and Subversion are also ready and running. If you want root, it's yours with a click. All of the log files are nicely presented in yet another tab. The system load and memory consumption appear in a dashboard-like tab. You never need to leave Eclipse/Aptana Studio.
While you're technically running on a single virtual machine, the servers have eight CPUs and they're set up to allow bursts of computation that can consume over 95 percent of those eight processors. This is more a nice feature that smooths bumps for occasional busy periods, not a way to get eight CPUs on the cheap.
Aptana Cloud is less revolutionary and more evolutionary. You can use all of the experience you have with the traditional tools again here. The buttons map pretty cleanly to the tasks that used to require Emacs in the shell and just simplify the process. If you need to poke around under the covers, or set up some other workflow, the opportunity is here.
Stax on Amazon EC2
While the other two solutions come built as plug-ins to Eclipse, Stax Networks offers a complete set of Web tools for creating and managing the projects. Everything starts with the Web. Then you download the source to your local computer for editing by invoking a command-line tool that handles downloads and redeployment. Then it's back to the Web for all of the management. I'm guessing you could switch from a single machine to a big, five-server cluster with just a few clicks at one of those computers they park in a hotel lobby to let you check in for your flight.
A wide variety of starting points is available from basic servlets to Apache Struts or Apache Wicket, all running on Tomcat. Stax also offers JRuby and Jython running on top of the same Java foundation. All can talk to MySQL databases running in the same cluster.
At this point in time, you download the code, build your application on your machine, and redeploy code with a command-line tool. This flexibility lets you use Ant, Eclipse, or any other Java tool to build the application. I wouldn't be surprised if Stax doesn't eventually integrate some of the wiki-like features from other Web sites into its tool and make it possible to do much of the building in your browser.
The Stax cloud, by the way, is just a subcloud of Amazon's EC2. Or maybe it's a virtual cloud. In any case, Stax Networks rents from Amazon and then turns around and rents to you. This means that you might want to use some of Amazon's other services, like S3, because they don't require a long trip across the Internet. They're all in the same server farm.