EDIT

package eu.etaxonomy.cdm.vaadin.view;

import java.net.URI;

public interface IAuthenticationComponent {

	public interface AuthenticationComponentListener {

        /**

         * @param uri

         * @param context

         * @param userName

         * @param password

         * @return

         */

        boolean login(URI uri, String context, String userName, String password);

    }

    public void addListener(AuthenticationComponentListener listener);

}