[hibernate-issues] how to generate mapping file from java file without annotation?

Hi : I am devoloping a webservice application. the main functions of the app is: 1. allow clients to upload user JavaBean classes.(normall JavaBean classes without hibernate annotation) 2. allow clients send instances of the JavaBean classes which they upload before. 3. save the instances which the clients sended into DB using hibernate. My problem is both @annotation and mapping files is not exist, how can i save these instances using hiberante ?? or is there anyway to generate either annotation or mapping files from normall JavaBean classes ?? Thanks