001    //$HeadURL: svn+ssh://rbezema@svn.wald.intevation.org/deegree/base/branches/2.2_testing/src/org/deegree/io/datastore/idgenerator/UUIDGenerator.java $
002    /*----------------    FILE HEADER  ------------------------------------------
003    
004     This file is part of deegree.
005     Copyright (C) 2001-2008 by:
006     EXSE, Department of Geography, University of Bonn
007     http://www.giub.uni-bonn.de/deegree/
008     lat/lon GmbH
009     http://www.lat-lon.de
010    
011     This library is free software; you can redistribute it and/or
012     modify it under the terms of the GNU Lesser General Public
013     License as published by the Free Software Foundation; either
014     version 2.1 of the License, or (at your option) any later version.
015    
016     This library is distributed in the hope that it will be useful,
017     but WITHOUT ANY WARRANTY; without even the implied warranty of
018     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
019     Lesser General Public License for more details.
020    
021     You should have received a copy of the GNU Lesser General Public
022     License along with this library; if not, write to the Free Software
023     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
024    
025     Contact:
026    
027     Andreas Poth
028     lat/lon GmbH
029     Aennchenstraße 19
030     53177 Bonn
031     Germany
032     E-Mail: poth@lat-lon.de
033    
034     Prof. Dr. Klaus Greve
035     Department of Geography
036     University of Bonn
037     Meckenheimer Allee 166
038     53115 Bonn
039     Germany
040     E-Mail: greve@giub.uni-bonn.de
041     
042     ---------------------------------------------------------------------------*/
043    package org.deegree.io.datastore.idgenerator;
044    
045    import java.util.Properties;
046    import java.util.UUID;
047    
048    import org.deegree.datatypes.Types;
049    import org.deegree.io.datastore.DatastoreTransaction;
050    import org.deegree.io.datastore.FeatureId;
051    import org.deegree.io.datastore.schema.MappedFeatureType;
052    import org.deegree.io.datastore.schema.MappedGMLId;
053    
054    /**
055     * Primary key and {@link FeatureId} generator that is based on UUIDs.
056     * 
057     * @author <a href="mailto:schneider@lat-lon.de">Markus Schneider </a>
058     * @author last edited by: $Author: apoth $
059     * 
060     * @version $Revision: 9342 $, $Date: 2007-12-27 13:32:57 +0100 (Do, 27 Dez 2007) $
061     */
062    public class UUIDGenerator extends IdGenerator {
063    
064        private long mac;
065    
066        private boolean macSet;
067    
068        /**
069         * Creates a new <code>UUIDGenerator</code> instance.
070         * <p>
071         * Supported configuration parameters: <table>
072         * <tr>
073         * <th>Name</th>
074         * <th>optional?</th>
075         * <th>Usage</th>
076         * </tr>
077         * <tr>
078         * <td>macAddress</td>
079         * <td>yes</td>
080         * <td>specify MAC address component of UUID</td>
081         * </tr>
082         * </table>
083         * 
084         * @param params
085         *            configuration parameters
086         * @throws IdGenerationException
087         */
088        public UUIDGenerator( Properties params ) throws IdGenerationException {
089            super( params );
090            String macAddress = params.getProperty( "macAddress" );
091            if ( macAddress != null ) {
092                long decoded;
093                try {
094                    decoded = Long.decode( macAddress );
095                } catch ( NumberFormatException e ) {
096                    throw new IdGenerationException( "Value for parameter 'macAddress': '" + macAddress
097                                                     + "' can not be decoded as Long." );
098                }
099                mac = decoded;
100                macSet = true;
101            }
102        }
103    
104        /**
105         * Returns a new primary key.
106         * 
107         * @param ta
108         *            datastore transaction (context)
109         * @return a new primary key.
110         * @throws IdGenerationException
111         *             if the generation of the id could not be performed
112         */
113        @Override
114        public String getNewId( DatastoreTransaction ta )
115                                throws IdGenerationException {
116            return "UUID_" + ( macSet ? new UUID( mac, (long) ( Math.random() * Long.MAX_VALUE ) ) : UUID.randomUUID() );
117        }
118    
119        /**
120         * Returns a new id for a feature of the given type.
121         * 
122         * @param ft
123         *            (mapped) feature type (irrelevant for this generator)
124         * @param ta
125         *            datastore transaction (context)
126         * @return a new feature id.
127         * @throws IdGenerationException
128         */
129        @Override
130        public FeatureId getNewId( MappedFeatureType ft, DatastoreTransaction ta )
131                                throws IdGenerationException {
132    
133            FeatureId fid = null;
134    
135            MappedGMLId fidDefinition = ft.getGMLId();
136            if ( fidDefinition.getKeySize() != 1 ) {
137                throw new IdGenerationException( "Cannot generate feature ids that are mapped to "
138                                                 + fidDefinition.getKeySize() + " columns." );
139            }
140            if ( fidDefinition.getIdFields()[0].getType() == Types.VARCHAR
141                 || fidDefinition.getIdFields()[0].getType() == Types.CHAR ) {
142                String uuidString = "UUID_"
143                                    + ( macSet ? new UUID( mac, (long) ( Math.random() * Long.MAX_VALUE ) )
144                                              : UUID.randomUUID() );
145                fid = new FeatureId( ft, new Object[] { uuidString } );
146            } else {
147                // TODO add handling of NUMERIC columns (>= 128 bit)
148                throw new IdGenerationException( "UUIDGenerator may currently only be used for VARCHAR fields." );
149            }
150            return fid;
151        }
152    }