/** * {@inheritDoc} **/ @Override protected final HandlerResult doAuthentication(final Credential credential) throws GeneralSecurityException, PreventedException { final UsernamePasswordCredential userPass = (UsernamePasswordCredential) credential; if (userPass.getUsername() == null) { throw new AccountNotFoundException("Username is null."); } final String transformedUsername= this.principalNameTransformer.transform(userPass.getUsername()); if (transformedUsername == null) { throw new AccountNotFoundException("Transformed username is null."); } userPass.setUsername(transformedUsername); return authenticateUsernamePasswordInternal(userPass); }