Exception thrown when SP requests a particular authentication method that is not configured

If an SP requests a specific mechanism and the IdP is not configured for that mechanism an exception is throw. This caused AuthenticationEngine line 319 does not check to see if there are methods remaining after filtering. Attached is a trace.

8:08:33.557 - DEBUG [edu.internet2.middleware.shibboleth.idp.authn.AuthenticationEngine:352] - Configured LoginHandlers: {urn:oasis:names:tc:SAML:2.0:ac:classes:unspecified=edu.internet2.middleware.shibboleth.idp.authn.provider.RemoteUserLoginHandler@ef7d74, urn:oasis:names:tc:SAML:2.0:ac:classes:PreviousSession=edu.internet2.middleware.shibboleth.idp.authn.provider.PreviousSessionLoginHandler@1157f77}
18:08:33.557 - DEBUG [edu.internet2.middleware.shibboleth.idp.authn.AuthenticationEngine:353] - Requested authentication methods: org.opensaml.xml.util.LazyList@1bca486
18:08:33.557 - DEBUG [edu.internet2.middleware.shibboleth.idp.authn.AuthenticationEngine:300] - Possible authentication handlers for this request: {urn:oasis:names:tc:SAML:2.0:ac:classes:PreviousSession=edu.internet2.middleware.shibboleth.idp.authn.provider.PreviousSessionLoginHandler@1157f77}
18:08:33.557 - DEBUG [edu.internet2.middleware.shibboleth.idp.authn.AuthenticationEngine:313] - Possible authentication handlers after filtering: {urn:oasis:names:tc:SAML:2.0:ac:classes:PreviousSession=edu.internet2.middleware.shibboleth.idp.authn.provider.PreviousSessionLoginHandler@1157f77}
18:08:33.558 - ERROR [edu.internet2.middleware.shibboleth.common.profile.ProfileRequestDispatcherServlet:85] - Error processing profile request
java.util.NoSuchElementException
at java.util.HashMap$HashIterator.nextEntry(HashMap.java:844) [na:1.5.0_14]
at java.util.HashMap$EntryIterator.next(HashMap.java:883) [na:1.5.0_14]
at java.util.HashMap$EntryIterator.next(HashMap.java:881) [na:1.5.0_14]
at edu.internet2.middleware.shibboleth.idp.authn.AuthenticationEngine.startUserAuthentication(AuthenticationEngine.java:320) [shibboleth-identityprovider-2.1.2.jar:na]
at edu.internet2.middleware.shibboleth.idp.authn.AuthenticationEngine.service(AuthenticationEngine.java:275) [shibboleth-identityprovider-2.1.2.jar:na]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717) [servlet-api.jar:na]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290) [catalina.jar:na]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) [catalina.jar:na]
at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:630) [catalina.jar:na]
at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:436) [catalina.jar:na]
at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:374) [catalina.jar:na]
at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:302) [catalina.jar:na]
at edu.internet2.middleware.shibboleth.idp.profile.saml2.SSOProfileHandler.performAuthentication(SSOProfileHandler.java:192) [shibboleth-identityprovider-2.1.2.jar:na]
at edu.internet2.middleware.shibboleth.idp.profile.saml2.SSOProfileHandler.processRequest(SSOProfileHandler.java:145) [shibboleth-identityprovider-2.1.2.jar:na]
at edu.internet2.middleware.shibboleth.idp.profile.saml2.SSOProfileHandler.processRequest(SSOProfileHandler.java:82) [shibboleth-identityprovider-2.1.2.jar:na]
at edu.internet2.middleware.shibboleth.common.profile.ProfileRequestDispatcherServlet.service(ProfileRequestDispatcherServlet.java:82) [shibboleth-common-1.1.2.jar:na]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717) [servlet-api.jar:na]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290) [catalina.jar:na]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) [catalina.jar:na]
at edu.internet2.middleware.shibboleth.idp.session.IdPSessionFilter.doFilter(IdPSessionFilter.java:77) [shibboleth-identityprovider-2.1.2.jar:na]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) [catalina.jar:na]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) [catalina.jar:na]
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233) [catalina.jar:na]
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191) [catalina.jar:na]
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128) [catalina.jar:na]
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) [catalina.jar:na]
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) [catalina.jar:na]
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:286) [catalina.jar:na]
at org.apache.jk.server.JkCoyoteHandler.invoke(JkCoyoteHandler.java:190) [tomcat-coyote.jar:na]
at org.apache.jk.common.HandlerRequest.invoke(HandlerRequest.java:283) [tomcat-coyote.jar:na]
at org.apache.jk.common.ChannelSocket.invoke(ChannelSocket.java:767) [tomcat-coyote.jar:na]
at org.apache.jk.common.ChannelSocket.processConnection(ChannelSocket.java:697) [tomcat-coyote.jar:na]
at org.apache.jk.common.ChannelSocket$SocketConnection.runIt(ChannelSocket.java:889) [tomcat-coyote.jar:na]
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:690) [tomcat-coyote.jar:na]
at java.lang.Thread.run(Thread.java:595) [na:1.5.0_14]