I am not sure exactly what you expect. Surely you searched for a utility for writing the SAS7BDAT format. I assume that you didn't find one for Java. It is a proprietary format that hasn't been released by SAS which means a bit more research is required - and perhaps writing of code on your part. For example, you will have to figure out the file format. There are some 'readers' for the file format (for example dsread: http://www.oview.co.uk/dsread/.) Perhaps one of them can help you figure out the file format necessary to write the format.
SAS apparently can import from CSV or from Excel so you could write to those file formats. And if you have SAS on you could try to automate the IMPORT proc perhaps.