Scala generic function fill type dynamicaly

Question

I am using a org.json4s for json read and write. The library containa method like this.

val ser = read[ContentObject](jsonString)

But,, i want to do something like.

val c = Class.forName(r.e)
val e = read[Login](URLDecoder.decode(r.c))

Because the object type and content is retrieve in a format of String. But this is not allow.

I would like to ask what is the right way to do this? The method write[T], what is T? Is it a Class[]??

Thank :D