private TokenProvider getTokenProvider() {
TokenProvider provider = null;
SecurityProvider securityProvider = getSecurityProvider();
Root root = getRoot();
if (root != null && securityProvider != null) {
AuthenticationConfiguration authConfig = getSecurityProvider().getConfiguration(AuthenticationConfiguration.class);
provider = authConfig.getTokenProvider(root);
}
if (provider == null && callbackHandler != null) {
try {
TokenProviderCallback tcCallback = new TokenProviderCallback();
callbackHandler.handle(new Callback[] {tcCallback});