类层次结构
- java.lang.Object 
       
- javax.security.auth.kerberos.EncryptionKey (implements javax.crypto.SecretKey)
 - javax.security.auth.kerberos.KerberosCredMessage (implements javax.security.auth.Destroyable)
 - javax.security.auth.kerberos.KerberosKey (implements javax.crypto.SecretKey)
 - javax.security.auth.kerberos.KerberosPrincipal (implements java.security.Principal, java.io.Serializable)
 - javax.security.auth.kerberos.KerberosTicket (implements javax.security.auth.Destroyable, javax.security.auth.Refreshable, java.io.Serializable)
 - javax.security.auth.kerberos.KeyTab
 - java.security.Permission (implements java.security.Guard, java.io.Serializable) 
         
- java.security.BasicPermission (implements java.io.Serializable) 
           
- javax.security.auth.kerberos.DelegationPermission (implements java.io.Serializable)
 
 - javax.security.auth.kerberos.ServicePermission (implements java.io.Serializable)
 
 - java.security.BasicPermission (implements java.io.Serializable)