content: /*
   * This library is part of OpenCms -
   * the Open Source Content Management System
   *
   * Copyright (c) Alkacon Software GmbH & Co. KG (https://www.alkacon.com)
   *
   * This library is free software; you can redistribute it and/or
   * modify it under the terms of the GNU Lesser General Public
   * License as published by the Free Software Foundation; either
   * version 2.1 of the License, or (at your option) any later version.
   *
   * This library is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
   * Lesser General Public License for more details.
   *
   * For further information about Alkacon Software, please see the
   * company website: https://www.alkacon.com
   *
   * For further information about OpenCms, please see the
   * project website: https://www.opencms.org
   *
   * You should have received a copy of the GNU Lesser General Public
   * License along with this library; if not, write to the Free Software
   * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
   */
  
  package org.opencms.ui.client;
  
  import org.opencms.ui.components.extensions.CmsHistoryExtension;
  import org.opencms.ui.shared.components.CmsHistoryState;
  
  import com.google.gwt.user.client.History;
  import com.vaadin.client.ServerConnector;
  import com.vaadin.client.communication.StateChangeEvent;
  import com.vaadin.client.extensions.AbstractExtensionConnector;
  import com.vaadin.shared.ui.Connect;
  
  /**
   * The history extension connector.<p>
   */
  @Connect(CmsHistoryExtension.class)
  public class CmsHistoryConnector extends AbstractExtensionConnector {
  
      /** Serial version id. */
      private static final long serialVersionUID = 1172858679530092378L;
  
      /**
       * @see com.vaadin.client.ui.AbstractConnector#getState()
       */
      @Override
      public CmsHistoryState getState() {
  
          return (CmsHistoryState)super.getState();
  
      }
  
      /**
       * @see com.vaadin.client.ui.AbstractConnector#onStateChanged(com.vaadin.client.communication.StateChangeEvent)
       */
      @Override
      public void onStateChanged(StateChangeEvent stateChangeEvent) {
  
          super.onStateChanged(stateChangeEvent);
  
          executeHistoryAction();
      }
  
      /**
       * @see com.vaadin.client.extensions.AbstractExtensionConnector#extend(com.vaadin.client.ServerConnector)
       */
      @Override
      protected void extend(ServerConnector target) {
  
          // nothing to do
      }
  
      /**
       * Executes the history action according to the history state.<p>
       */
      private void executeHistoryAction() {
  
          CmsHistoryState state = getState();
          if (state.isHistoryBack()) {
              History.back();
          } else if (state.isHistoryForward()) {
              History.forward();
          }
      }
  }
  