Eclipse Luna - how to collapse / collapse private javascript function

Question

I am using the Eclipse Luna JavaEE IDE for web developers

How to collapse a private javascript function inside a class?

  var ClientBattle = function(wtfClient){

        this.setDataPet = function(){
           // code in here can collapse
        }

        function generateBox(){
          // code in here cannot collapse
        }

    }

any plugin will also appreciate