@Override
  public boolean supports(Class<? extends Object> auth) {
    return KerberosServiceRequestToken.class.isAssignableFrom(auth);
  }
AmbariKerberosAuthenticationProvider is an {@link org.springframework.security.authentication.AuthenticationProvider}
implementation used to authenticate users using a Kerberos ticket.
<p>
In order for this provider to be usable, Kerberos authentication must be enabled. This may be done
using the <code>ambari-server setup-kerberos</code> CLI.
<p>
This implementation supports Trusted Proxy authentication.
ambari-server/src/main/java/org/apache/ambari/server/security/authentication/kerberos/AmbariKerberosAuthenticationProvider.java