The Mule server fails to deploy due to this error.
4 answers

It is unlikely that your problem is that you lack a JDK since you can start the Mule instance and get to the point where you get the error message.
However the Map interface in java.util is spelled with a capital 'M'.
So make sure that if you referenced it in your flow (for example as an returnClass) you spell it "java.util.Map" with a capital M.