I am looking for a Framework (Java is preferred), that will run on Goggle App Engine, but is also possible to switch over to another cloud vendor like maybe AWS-Beanstalk or OpenStack. For sure you will have to change some properties files and stuff but I don’t want to change much of my code.
And also I’m quite concerned about the Performance, the App should with decent performance even on the Free GAE offer. With growing size I maybe commit to payment, however as a starting point payment isn’t planned.
So my first thought was the Spring Framework, but I have no experience with it and so I am not sure if it fits my needs? Are there any serious competitors even for business applications?
As a final point if have to state that I am quite experienced with developing Java but haven’t done anything with a java framework (in aspect to an application framework) yet. The only Framework I’ve used till now was Symfony.
You can check the compatibility of different Java frameworks in: Will it play in GAE?
Spring is composed by different modules. Some of them will run out-of-the-box, some of them require some patches. It really depends on the classes you can run in GAE, defined in the Google class whitelist.
IMHO, I find it anoying each time I have to fix a library in order to make it work on GAE, so when it is possible I use full Java spec support PaaS, like Heroku.