code: private boolean setupKerberosKeys() {
          if (kerberosKeys != null) {
              return true;
          }
          try {
              final AccessControlContext acc = getAccSE();
              kerberosKeys = AccessController.doPrivileged(
                  // Eliminate dependency on KerberosKey
                  new PrivilegedExceptionAction<SecretKey[]>() {
                  public SecretKey[] run() throws Exception {
                      // get kerberos key for the default principal
                      return Krb5Helper.getServerKeys(acc);
                          }});
  
              // check permission to access and use the secret key of the
              // Kerberized "host" service
              if (kerberosKeys != null && kerberosKeys.length > 0) {
                  if (debug != null && Debug.isOn("handshake")) {
                      for (SecretKey k: kerberosKeys) {
                          System.out.println("Using Kerberos key: " +
                              k);
                      }
                  }
  
                  String serverPrincipal =
                      Krb5Helper.getServerPrincipalName(kerberosKeys[0]);
                  SecurityManager sm = System.getSecurityManager();
                  try {
                     if (sm != null) {
                        // Eliminate dependency on ServicePermission
                        sm.checkPermission(Krb5Helper.getServicePermission(
                            serverPrincipal, "accept"), acc);
                     }
                  } catch (SecurityException se) {
                     kerberosKeys = null;
                     // %%% destroy keys? or will that affect Subject?
                     if (debug != null && Debug.isOn("handshake"))
                        System.out.println("Permission to access Kerberos"
                                  + " secret key denied");
                     return false;
                  }
              }
              return (kerberosKeys != null && kerberosKeys.length > 0);
          } catch (PrivilegedActionException e) {
              // Likely exception here is LoginExceptin
              if (debug != null && Debug.isOn("handshake")) {
                  System.out.println("Attempt to obtain Kerberos key failed: "
                                  + e.toString());
              }
              return false;
          }
      }
docs: Retrieve the Kerberos key for the specified server principal
  from the JAAS configuration file.
  
  @return true if successful, false if not available or invalid