EDIT

package eu.etaxonomy.cdm.vaadin.ui;

import java.net.URI;

import java.util.logging.Logger;

import com.vaadin.navigator.Navigator;

import com.vaadin.server.Page;

import com.vaadin.server.VaadinRequest;

import com.vaadin.server.VaadinServlet;

import com.vaadin.server.VaadinSession;

import com.vaadin.ui.UI;

import eu.etaxonomy.cdm.vaadin.util.CdmVaadinAuthentication;

import eu.etaxonomy.cdm.vaadin.view.AuthenticationView;

public abstract class AbstractAuthenticatedUI extends CdmBaseUI {

	/**

	 *

	 */

	private static final long serialVersionUID = 1L;

	Navigator navigator;

	private static final String AUTHENTICATION_VIEW = "abstractAuthenticatedUI";

	private boolean ignoreAuthentication = false;

	private final static Logger logger =

			Logger.getLogger(AbstractAuthenticatedUI.class.getName());

	@Override

	protected void init(VaadinRequest request) {

	    super.init(request);

        // Create a navigator to control the views

        navigator = new Navigator(this, this);

        AuthenticationView av = new AuthenticationView();

        navigator.addView(AUTHENTICATION_VIEW, av);

        // Create and register the views

        CdmVaadinAuthentication cvAuthentication = (CdmVaadinAuthentication) VaadinSession.getCurrent().getAttribute(CdmVaadinAuthentication.KEY);

        doInit(request);

        URI uri = Page.getCurrent().getLocation();

        String context = VaadinServlet.getCurrent().getServletContext().getContextPath();

        if(ignoreAuthentication || (cvAuthentication != null && cvAuthentication.isAuthenticated(uri, context))) {

            if(cvAuthentication != null) {

                cvAuthentication.setSecurityContextAuthentication(uri, context);

            }

            UI.getCurrent().getNavigator().navigateTo(getFirstViewName());

        } else {

            UI.getCurrent().getNavigator().navigateTo(AUTHENTICATION_VIEW);

        }

	}

	protected abstract void doInit(VaadinRequest request);

	public abstract String getFirstViewName();

	public void setIgnoreAuthentication(boolean ignoreAuthentication) {

	    this.ignoreAuthentication = ignoreAuthentication;

	}

}