You can capture the user principal by using the openssoclientSDK.
Add clientSDK into your classpath (openssoclientSDK.jar). Deploy the opensso-client-jdk15.war (you can use the appropriate war for your jre).
Start your application server and open open-sso-client webapp and follow the instructions in this documentation http://docs.sun.com/app/docs/doc/820-3748/gieyu?a=view
Use the following code into the Servlet,
SSOTokenManager ssoTokenManager = SSOTokenManager.getInstance();
SSOToken ssoToken = ssoTokenManager.createSSOToken(request);
Principal principal = ssoToken.getPrincipal();
principal.getName();
Common Errors:
SSO Exception Invalid Session: Service URL not found:session
Solution: Deploy and configure the open-sso-client webapp
If you getting redirection error(infinite loops):
Login into the SSO server check/uncheck (depends on the server) the encode cookie value.
