Patch Set 7: No score; No score

Christian wrote:
>This was my first idea, but it didn't worked out when trying to implement it. Problem is that every Command implements call() but throws a different set of exceptions Although we have a common interface the implementations differ in the set of exceptions they throw.

The call interface that you implement already has "throws Exception". Do we need it?

As for the state state. This is a public API, which means we want something that can stay as it is, Ideally forever. If it was an internal thing it would be less important, but it leaks through the setState (now setCallable) method. 

Also: Spelling error in commit message "This API is intendet"