It really depends on what you are trying to acheive.  For instance, if
you want to be able to view the models as part of a java application,
j3d might be a good choice.  If you simply want to put the models on a
web-page somewhere you can either create a viewing applet using j3d or
you can require the user to download a viewing program (Cortona comes
to mind for VRML, not sure if it can load 3D Studio models) and simply
provide a link to your model file.

I'm not sure how up-to-date this list is, but in any case, this is a
list of java 3d loaders for the model type you mentioned and more:

http://java3d.j3d.org/utilities/loaders.html

I just recently downloaded CyberX3D from this list so I could load some
3D models into an application and interact with them.  I'll leave it to
you to decide which loader package(s) is right for you (if it is even
necessary at all).

--Norman