In order to read external files from Java you could use a JDBC-driver
to access the file through a server. For instance if you want to read
a SAS-dataset you could use a the JDBC-driver from SAS Institute.
However a SAS-session has to be running in order to access the data,
as I understand it.

Is it possible just to read a SAS-dataset without a running SAS-
session? In my mind a SAS-dataset is just a certain filetype
like '.txt' is a filetype, which is read quite easily by Java. In
many cases my SAS-datasets are placed on my own client-machine and
not on a remote server.