001/*
002 * This library is part of OpenCms -
003 * the Open Source Content Management System
004 *
005 * Copyright (c) Alkacon Software GmbH & Co. KG (http://www.alkacon.com)
006 *
007 * This library is free software; you can redistribute it and/or
008 * modify it under the terms of the GNU Lesser General Public
009 * License as published by the Free Software Foundation; either
010 * version 2.1 of the License, or (at your option) any later version.
011 *
012 * This library is distributed in the hope that it will be useful,
013 * but WITHOUT ANY WARRANTY; without even the implied warranty of
014 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
015 * Lesser General Public License for more details.
016 *
017 * For further information about Alkacon Software, please see the
018 * company website: http://www.alkacon.com
019 *
020 * For further information about OpenCms, please see the
021 * project website: http://www.opencms.org
022 *
023 * You should have received a copy of the GNU Lesser General Public
024 * License along with this library; if not, write to the Free Software
025 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
026 */
027
028package org.opencms.i18n;
029
030import org.opencms.util.CmsStringUtil;
031
032import java.util.Map;
033
034import com.google.common.base.Optional;
035
036/**
037 * Message key fallback handler which replaces a given set of prefixes with alternative prefixes.<p>
038 */
039public class CmsReplaceMessageKeyPrefix implements CmsMultiMessages.I_KeyFallbackHandler {
040
041    /** The prefix substitutions. */
042    private Map<String, String> m_substitutions;
043
044    /**
045     * Creates a new instance.<p>
046     *
047     * @param configuration a pipe-separated list of colon-separated key-value pairs, where the key is the prefix and the value is the replacement
048     */
049    public CmsReplaceMessageKeyPrefix(String configuration) {
050
051        m_substitutions = CmsStringUtil.splitAsMap(configuration, "|", ":");
052
053    }
054
055    /**
056     * @see org.opencms.i18n.CmsMultiMessages.I_KeyFallbackHandler#getFallbackKey(java.lang.String)
057     */
058    public Optional<String> getFallbackKey(String key) {
059
060        for (String prefix : m_substitutions.keySet()) {
061            if (key.startsWith(prefix)) {
062                return Optional.fromNullable(m_substitutions.get(prefix) + key.substring(prefix.length()));
063            }
064        }
065        return Optional.absent();
066    }
067
068}