001    /**
002     * 
003     * $Revision: 13085 $ $Date: 2008-02-06 18:27:24 +0100 (Mi, 06 Feb 2008) $
004     *
005     * This file is part of ** M y C o R e **
006     * Visit our homepage at http://www.mycore.de/ for details.
007     *
008     * This program is free software; you can use it, redistribute it
009     * and / or modify it under the terms of the GNU General Public License
010     * (GPL) as published by the Free Software Foundation; either version 2
011     * of the License or (at your option) any later version.
012     *
013     * This program is distributed in the hope that it will be useful, but
014     * WITHOUT ANY WARRANTY; without even the implied warranty of
015     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
016     * GNU General Public License for more details.
017     *
018     * You should have received a copy of the GNU General Public License
019     * along with this program, normally in the file license.txt.
020     * If not, write to the Free Software Foundation Inc.,
021     * 59 Temple Place - Suite 330, Boston, MA  02111-1307 USA
022     *
023     **/
024    
025    package org.mycore.datamodel.common;
026    
027    import java.util.Collection;
028    import java.util.Map;
029    import java.util.concurrent.ConcurrentHashMap;
030    import java.util.concurrent.ConcurrentLinkedQueue;
031    
032    import org.mycore.common.MCRCatchException;
033    
034    /**
035     * This exception holds information about a link condition that did not allow a
036     * certain action to be performed.
037     * 
038     * As this exception does not extend RuntimeException it has to be caught for
039     * data integrity reasons.
040     * 
041     * @author Thomas Scheffler (yagee)
042     */
043    public class MCRActiveLinkException extends MCRCatchException {
044    
045        /**
046         * 
047         */
048        private static final long serialVersionUID = 1L;
049    
050        Map<String, Collection<String>> linkTable = new ConcurrentHashMap<String, Collection<String>>();
051    
052        /**
053         * 
054         * @return a Hashtable with destinations (key) and List of sources (value)
055         */
056        public Map<String, Collection<String>> getActiveLinks() {
057            return linkTable;
058        }
059    
060        /**
061         * collects information on active links that do not permit a certain action
062         * on the repository.
063         * 
064         * @param source
065         *            the source of a link
066         * @param dest
067         *            the destination of a link
068         */
069        public void addLink(String source, String dest) {
070            if (!linkTable.containsKey(dest)) {
071                linkTable.put(dest, new ConcurrentLinkedQueue<String>());
072            }
073            linkTable.get(dest).add(source);
074        }
075    
076        /**
077         * @see MCRCatchException#MCRCatchException(String)
078         */
079        public MCRActiveLinkException(String message) {
080            super(message);
081        }
082    
083        /**
084         * @see MCRCatchException#MCRCatchException(String, Throwable)
085         */
086        public MCRActiveLinkException(String message, Throwable cause) {
087            super(message, cause);
088        }
089    
090    }