package org.apereo.cas.authentication;
<BUG>import org.apache.shiro.util.Assert;</BUG>
import org.apereo.cas.authentication.policy.AnyAuthenticationPolicy;
import org.apereo.cas.authentication.principal.NullPrincipal;
import org.apereo.cas.authentication.principal.PrincipalResolver;
import org.apereo.cas.services.ServicesManager;
import org.apereo.cas.support.events.authentication.CasAuthenticationPolicyFailureEvent;
import org.apereo.cas.support.events.authentication.CasAuthenticationTransactionFailureEvent;
import org.slf4j.Logger;
<BUG>import org.slf4j.LoggerFactory;
import java.security.GeneralSecurityException;</BUG>
import java.util.Collection;

package org.apereo.cas.authentication;
import org.apereo.cas.authentication.policy.AnyAuthenticationPolicy;
import org.apereo.cas.authentication.principal.NullPrincipal;
import org.apereo.cas.authentication.principal.PrincipalResolver;
import org.apereo.cas.services.ServicesManager;
import org.apereo.cas.support.events.authentication.CasAuthenticationPolicyFailureEvent;
import org.apereo.cas.support.events.authentication.CasAuthenticationTransactionFailureEvent;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.util.Assert;
import java.security.GeneralSecurityException;
import java.util.Collection;
