001 //$HeadURL: https://svn.wald.intevation.org/svn/deegree/base/branches/2.3_testing/src/org/deegree/io/datastore/sql/idgenerator/DBSeqIdGenerator.java $
002 /*----------------------------------------------------------------------------
003 This file is part of deegree, http://deegree.org/
004 Copyright (C) 2001-2009 by:
005 Department of Geography, University of Bonn
006 and
007 lat/lon GmbH
008
009 This library is free software; you can redistribute it and/or modify it under
010 the terms of the GNU Lesser General Public License as published by the Free
011 Software Foundation; either version 2.1 of the License, or (at your option)
012 any later version.
013 This library is distributed in the hope that it will be useful, but WITHOUT
014 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
015 FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
016 details.
017 You should have received a copy of the GNU Lesser General Public License
018 along with this library; if not, write to the Free Software Foundation, Inc.,
019 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
020
021 Contact information:
022
023 lat/lon GmbH
024 Aennchenstr. 19, 53177 Bonn
025 Germany
026 http://lat-lon.de/
027
028 Department of Geography, University of Bonn
029 Prof. Dr. Klaus Greve
030 Postfach 1147, 53001 Bonn
031 Germany
032 http://www.geographie.uni-bonn.de/deegree/
033
034 e-mail: info@deegree.org
035 ----------------------------------------------------------------------------*/
036 package org.deegree.io.datastore.sql.idgenerator;
037
038 import java.sql.Connection;
039 import java.util.Properties;
040
041 import org.deegree.io.datastore.Datastore;
042 import org.deegree.io.datastore.DatastoreException;
043 import org.deegree.io.datastore.DatastoreTransaction;
044 import org.deegree.io.datastore.FeatureId;
045 import org.deegree.io.datastore.idgenerator.IdGenerationException;
046 import org.deegree.io.datastore.idgenerator.IdGenerator;
047 import org.deegree.io.datastore.schema.MappedFeatureType;
048 import org.deegree.io.datastore.schema.MappedGMLId;
049 import org.deegree.io.datastore.sql.AbstractSQLDatastore;
050 import org.deegree.io.datastore.sql.transaction.SQLTransaction;
051
052 /**
053 * Feature id generator that uses an SQL sequence to create new values.
054 *
055 * @author <a href="mailto:schneider@lat-lon.de">Markus Schneider </a>
056 * @author last edited by: $Author: mschneider $
057 *
058 * @version $Revision: 18195 $, $Date: 2009-06-18 17:55:39 +0200 (Do, 18. Jun 2009) $
059 */
060 public class DBSeqIdGenerator extends IdGenerator {
061
062 private String sequenceName;
063
064 private int offset = -1;
065
066 /**
067 * Creates a new <code>DBSeqIdGenerator</code> instance.
068 * <p>
069 * Supported configuration parameters:
070 * <table border="1">
071 * <tr>
072 * <th>Name</th>
073 * <th>optional?</th>
074 * <th>Usage</th>
075 * </tr>
076 * <tr>
077 * <td>sequence</td>
078 * <td>no</td>
079 * <td>name of the SQL sequence to be used</td>
080 * </tr>
081 * <tr>
082 * <td>offset</td>
083 * <td>yes</td>
084 * <td>integer value, if omitted the next value of the sequence is used (default)<br>
085 * otherwise the current value + offset is used</td>
086 * </tr>
087 * </table>
088 *
089 * @param params
090 * configuration parameters
091 * @throws IdGenerationException
092 */
093 public DBSeqIdGenerator( Properties params ) throws IdGenerationException {
094 super( params );
095 this.sequenceName = params.getProperty( "sequence" );
096 if ( this.sequenceName == null ) {
097 throw new IdGenerationException( "DBSeqIdGenerator requires 'sequence' parameter." );
098 }
099 String offsetString = params.getProperty( "offset" );
100 if ( offsetString != null ) {
101 try {
102 offset = Integer.parseInt( offsetString );
103 } catch ( NumberFormatException e ) {
104 throw new IdGenerationException( "DBSeqIdGenerator 'offset' parameter must be an integer value." );
105 }
106 }
107 }
108
109 /**
110 * Returns the name of the used sequence.
111 *
112 * @return the name of the used sequence
113 */
114 public String getSequenceName() {
115 return this.sequenceName;
116 }
117
118 /**
119 * Returns a new primary key.
120 *
121 * @param ta
122 * datastore transaction (context)
123 * @return a new primary key.
124 * @throws IdGenerationException
125 * if the generation of the id could not be performed
126 */
127 @Override
128 public Object getNewId( DatastoreTransaction ta )
129 throws IdGenerationException {
130 if ( !( ta instanceof SQLTransaction ) ) {
131 throw new IllegalArgumentException( "DBSeqIdGenerator can only be used with SQL datastores." );
132 }
133
134 Object pk;
135 try {
136 AbstractSQLDatastore ds = (AbstractSQLDatastore) ta.getDatastore();
137 Connection conn = ( (SQLTransaction) ta ).getConnection();
138 if (offset == -1) {
139 pk = ds.getSequenceNextVal( conn, this.sequenceName );
140 } else {
141 pk = ds.getSequenceCurrValPlusOffset( conn, this.sequenceName, offset );
142 }
143 } catch ( DatastoreException e ) {
144 throw new IdGenerationException( e.getMessage(), e );
145 }
146 return pk;
147 }
148
149 /**
150 * Returns a new id for a feature of the given type.
151 *
152 * @param ft
153 * (mapped) feature type
154 * @return a new feature id.
155 * @throws IdGenerationException
156 * if the generation of the id could not be performed
157 */
158 @Override
159 public FeatureId getNewId( MappedFeatureType ft, DatastoreTransaction ta )
160 throws IdGenerationException {
161
162 MappedGMLId fidDefinition = ft.getGMLId();
163 if ( fidDefinition.getKeySize() != 1 ) {
164 throw new IdGenerationException( "Cannot generate feature ids that are mapped to "
165 + fidDefinition.getKeySize() + " columns." );
166 }
167
168 Datastore ds = ft.getGMLSchema().getDatastore();
169 if ( !( ds instanceof AbstractSQLDatastore ) ) {
170 throw new IllegalArgumentException( "DBSeqIdGenerator can only be used with SQL datastores." );
171 }
172
173 Object fidNucleus;
174 try {
175 fidNucleus = ( (AbstractSQLDatastore) ds ).getSequenceNextVal( ( (SQLTransaction) ta ).getConnection(),
176 this.sequenceName );
177 } catch ( DatastoreException e ) {
178 throw new IdGenerationException( e.getMessage(), e );
179 }
180
181 FeatureId fid = new FeatureId( ft, new Object[] { fidNucleus } );
182 return fid;
183 }
184 }