title: How do I talk to ADFS from Java?
body: <p>We have a website running on Caucho Resin. It's written primarily in Java using JSP. We have our own custom authentication on the site. (We're not using any third party authentication frameworks.) We would now like to support federation using SAML. Primarily, the IdPs will be running ADFS, but my question is about SAML. In particular, <strong>how do I federate with the upstream IdPs from our Java app</strong> either using OpenSAML, Shibboleth or some other Java-compatible option?</p>
  <p>EDIT: Another option would be OAuth. Pros? Cons?</p>