It was done as we had a security audit and found some issues. I'm going to be brutally honest with you, at this point the "process" is arbitrary. You said you have not been here long so I will tell you that we are very open to feedback about how the system works and what we add to it. We are also very active and very responsive in the community. We will post the whitelist in our docs and we are open to suggestions about what is allowed and what is not.
That being said, we are not an open source project and so we do not release our source code and we are also not creating a development environment. We are creating a home automation hub that allows for coding extensibility within our sandbox. That sandbox is there to protect you and to protect us. We had to make some choices on white listing based on existing apps and drivers to allow all existing code to function. For instance if you try to use Scanner on Smarthings you will also get a security error. I did not see a reason to add that class in based on the code listed above.
I understand wanting to do advanced programming but we still have to maintain the security of our system. I myself have been a Java developer since 2002, so I can understand wanting to use various classes and libraries, however there are some great features in Groovy that allow you to do so much more than you can in Java.
There are plenty of people here on the forum to give help and suggestions. If there are classes that you feel you need, please bring them up and we can discuss.
