I agree a def will solve the problem, performance might suffer a little bit as the format-pattern has to be parsed again and again in the constructor. Cloning seems to be faster then creating :-)

```scala
private val dateFormatTemplate = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'") //use ISO_8601 format
val dateFormat = dateFormatTemplate.clone.asInstanceOf[SimpleDateFormat]
```