I have a project and I need help... The idea is a web application that allows users to sign a pdf located on server via a jar file (which is also on server) that take a pdf and PKCS#12 file (.p12 or .pfx) and generate a digitally signed PDF.

1. How is it possible to make the signing process take place on clientside using the .jar file ??
   
2. Or how can I recieve the user's PKCS#12 file and use it on server to allow user to sign the pdf without saving it on server (serverside)??

any helpful Ideas or recommandations!