//$Header: /home/deegree/jail/deegreerepository/deegree/src/org/deegree/io/datastore/idgenerator/IdGenerator.java,v 1.7 2006/09/26 16:43:22 mschneider Exp $
/*---------------- FILE HEADER ------------------------------------------
This file is part of deegree.
Copyright (C) 2001-2006 by:
EXSE, Department of Geography, University of Bonn
http://www.giub.uni-bonn.de/deegree/
lat/lon GmbH
http://www.lat-lon.de
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.
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
Contact:
Andreas Poth
lat/lon GmbH
Aennchenstraße 19
53177 Bonn
Germany
E-Mail: poth@lat-lon.de
Prof. Dr. Klaus Greve
Department of Geography
University of Bonn
Meckenheimer Allee 166
53115 Bonn
Germany
E-Mail: greve@giub.uni-bonn.de
---------------------------------------------------------------------------*/
package org.deegree.io.datastore.idgenerator;
import java.lang.reflect.Constructor;
import java.util.Properties;
import java.util.ResourceBundle;
import org.deegree.io.datastore.DatastoreTransaction;
import org.deegree.io.datastore.FeatureId;
import org.deegree.io.datastore.schema.MappedFeatureType;
/**
* Abstract base class for generators that are used to create primary keys (especially
* {@link FeatureId}s).
*
* @author <a href="mailto:schneider@lat-lon.de">Markus Schneider </a>
* @author last edited by: $Author: mschneider $
*
* @version $Revision: 1.7 $, $Date: 2006/09/26 16:43:22 $
*/
public abstract class IdGenerator {
/** Default generator type based on UUIDs. */
public static String TYPE_UUID = "UUID";
private static final String BUNDLE_NAME = "org.deegree.io.datastore.idgenerator.idgenerator";
private static final ResourceBundle RESOURCE_BUNDLE = ResourceBundle.getBundle( BUNDLE_NAME );
protected Properties params;
protected MappedFeatureType ft;
/**
* Creates a new <code>IdGenerator</code> instance.
*
* @param params
* configuration parameters
*/
protected IdGenerator (Properties params) {
this.params = params;
}
/**
* Returns a new primary key.
*
* @param ta
* datastore transaction (context)
* @return a new primary key.
* @throws IdGenerationException
* if the generation of the id could not be performed
*/
public abstract Object getNewId( DatastoreTransaction ta ) throws IdGenerationException;
/**
* Returns a new id for a feature of the given type.
*
* @param ft
* feature type
* @param ta
* datastore transaction (context)
* @return a new feature id.
* @throws IdGenerationException
*/
public abstract FeatureId getNewId( MappedFeatureType ft, DatastoreTransaction ta )
throws IdGenerationException;
/**
* Returns a concrete <code>IdGenerator</code> instance which is identified by the given type
* code.
*
* @param type
* type code
* @param params
* initialization parameters for the IdGenerator
* @return concrete IdGenerator instance
*/
public static final IdGenerator getInstance (String type, Properties params) {
IdGenerator generator = null;
try {
String className = RESOURCE_BUNDLE.getString( type );
Class idGeneratorClass = Class.forName( className );
// get constructor
Class [] parameterTypes = new Class [] { Properties.class };
Constructor constructor = idGeneratorClass.getConstructor(parameterTypes);
// call constructor
Object arglist[] = new Object[] { params };
generator = (IdGenerator) constructor.newInstance(arglist);
} catch (Exception e) {
e.printStackTrace();
// TODO WTF is error message not propagated here?
throw new RuntimeException( "Could not instantiate IdGenerator with type '"
+ type + "': " + e.getMessage() );
}
return generator;
}
}
/* ********************************************************************
Changes to this class. What the people have been up to:
$Log: IdGenerator.java,v $
Revision 1.7 2006/09/26 16:43:22 mschneider
Javadoc corrections + fixed warnings.
Revision 1.6 2006/04/06 20:25:32 poth
*** empty log message ***
Revision 1.5 2006/04/04 20:39:44 poth
*** empty log message ***
Revision 1.4 2006/03/30 21:20:29 poth
*** empty log message ***
Revision 1.3 2006/03/28 13:35:36 mschneider
Changed getNewId() so transaction context (DatastoreTransaction) and thus JDBC connection is accessible in the method.
Revision 1.2 2006/02/22 00:21:44 mschneider
Renamed AbstractDatastore to Datastore.
Revision 1.1 2006/02/17 14:33:06 mschneider
Former GMLIdGenerator.
Revision 1.2 2006/02/04 20:06:57 mschneider
Changed return type for getNewId () to FeatureId.
Revision 1.1 2006/02/03 14:40:13 mschneider
Initial version.
********************************************************************** */