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.i18n;
  
  import org.opencms.util.CmsStringUtil;
  
  import java.util.Map;
  
  import com.google.common.base.Optional;
  
  /**
   * Message key fallback handler which replaces a given set of prefixes with alternative prefixes.<p>
   */
  public class CmsReplaceMessageKeyPrefix implements CmsMultiMessages.I_KeyFallbackHandler {
  
      /** The prefix substitutions. */
      private Map<String, String> m_substitutions;
  
      /**
       * Creates a new instance.<p>
       *
       * @param configuration a pipe-separated list of colon-separated key-value pairs, where the key is the prefix and the value is the replacement
       */
      public CmsReplaceMessageKeyPrefix(String configuration) {
  
          m_substitutions = CmsStringUtil.splitAsMap(configuration, "|", ":");
  
      }
  
      /**
       * @see org.opencms.i18n.CmsMultiMessages.I_KeyFallbackHandler#getFallbackKey(java.lang.String)
       */
      public Optional<String> getFallbackKey(String key) {
  
          for (String prefix : m_substitutions.keySet()) {
              if (key.startsWith(prefix)) {
                  return Optional.fromNullable(m_substitutions.get(prefix) + key.substring(prefix.length()));
              }
          }
          return Optional.absent();
      }
  
  }
  