Define datatype w/o creating a new instance

Is it possible to define a datatype without create a new instance of one and repopulating?

I am passing a bean where a couple of the properties are arrays of other beans. Because of this i am unable to access the getter/setter methods of the bean as the data type object isn't defined. If i can define the data type object when its received then i'll have access to those getter/setters.

Thanks!