This library builds on openid4java library and implements the server-side and client-side OpenID protocols.
To use this library, you need to subtype the Session class and provides the logic that actually authenticates the user on the server-side (this information is then sent to the OpenID client requesting authentication.)
The OpenIDServer class is the object you bind to the URL space. Normally this is a singleton object.
To use the client side of this library, you instanciate OpenIDSession class per session and binds it somewhere in the URL space. You call this object's authenticate() method and obtain the OpenIDIdentity which represents the authenticated user.
If you call this method when the current user is not authenticated, an HttpResponse object is thrown to redirect the user to OpenID server for authentication, so the HTTP request that calls into the authenticate method better be side-effect free.