How to set groovysdk on mac in IntelliJ IDEA

The solution works for:
Groovy 2.4.12
IntelliJ IDEA 2017.2.6
macOS 10.12.6
Homebrew 1.5.10
It should work with other versions too.


STORY:
    I tried to Config groovy SDK to use in IntelliJ IDEA ... but you need specific path which is .. something like that: /usr/local/Cellar/groovy/x.y.z/ libexec but I couldn't see usr folder. 
As it turns out you need to use a magical shortcut to enable a view of hidden files/folder in Finder on Mac.
How?

SOLUTION:

1. Go to Project Structure
2. Go to Global Libraries
3. Press +
4. Select Java 
5. In Finder, press  ⌘⇧. ( Command key, SHIFT key  dot key a the same time ) to enable 'view hidden files' mode
6. Go to top level (MachintoshHD)
7. go to /usr/local/Cellar/groovy/x.y.z/libexec and press open if you don't see usr folder... perform step 5 (and ensure you have all privileges required) 
8. Press create
9. Done :)