I have a date variable
var date: Date = new Date()
then I have converted this date to String:
var dateStr = date.toString(
I see a couple of problems in your code, but this works fine:
scala> val format = new java.text.SimpleDateFormat("dd-MM-yyyy")
format: java.text.SimpleDateFormat = java.text.SimpleDateFormat@9586200
scala> format.format(new java.util.Date())
res4: java.lang.String = 21-03-2011
scala> format.parse("21-03-2011")
res5: java.util.Date = Mon Mar 21 00:00:00 CET 2011