Which PaaS provider could I consider for deploy my app in the cloud without much pain, ie, change structure or source code is not necessary and a provider that offers a good support for ides or command line too?
Some stenches and drawbacks to evaluate for which one in the list above ?
Looks like Jelastic is the most suitable for your needs - easy to start, does not required the code changes at all, integration with Eclipse and JetBrains, different ways to deploy your app, very good performance and auto scalability.
CloudBees and Heroku have many restrictions - no public IP addresses and using A records to point external domains to apps is not supported; they do not allow to use custom ports - it means an app can only listen 80 and 443 ports; limited access to the file system - many redesign issues are related to this restriction; multicast is not supported; no vertical scaling - you should pay for the limit of virtual boxes, not for the real usage. More detailed description of benefits from the vertical scaling is here http://cloud.dzone.com/articles/truth-about-paas-vertical