Token<DelegationTokenIdentifier> dt =
new Token<DelegationTokenIdentifier>();
dt.decodeFromUrlString(delegationParam);
DelegationTokenManager tokenManager =
HttpFSServerWebApp.get().get(DelegationTokenManager.class);
UserGroupInformation ugi = tokenManager.verifyToken(dt);
final String shortName = ugi.getShortUserName();
// creating a ephemeral token
token = new AuthenticationToken(shortName, ugi.getUserName(),
getType());