org.deegree.io.datastore.sql.idgenerator
Class DBMaxIdGenerator

java.lang.Object
  org.deegree.io.datastore.idgenerator.IdGenerator
      org.deegree.io.datastore.sql.idgenerator.DBMaxIdGenerator

public class DBMaxIdGenerator
extends IdGenerator

Feature id generator that produces successive (+1) values and retrieves its start value from the specified table value (the maximum stored in the field).

Please note that aborted transactions will also increase ids, so feature ids may be skipped.

Version:

$Revision: 6588 $, $Date: 2007-04-11 17:31:29 +0200 (Mi, 11. Apr 2007) $

Author:

Christoph Pollmann, Markus Schneider, last edited by: $Author: mschneider $

Field Summary

Fields inherited from class org.deegree.io.datastore.idgenerator.IdGenerator

ft, params, TYPE_UUID

Constructor Summary

DBMaxIdGenerator(Properties params)
Creates a new DBMaxIdGenerator instance.

Method Summary

Object	getNewId(DatastoreTransaction ta) Returns a new primary key.
FeatureId	getNewId(MappedFeatureType ft, DatastoreTransaction ta) Returns a new id for a feature of the given type.

Methods inherited from class org.deegree.io.datastore.idgenerator.IdGenerator

getInstance

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

DBMaxIdGenerator

public DBMaxIdGenerator(Properties params)
                 throws IdGenerationException

Creates a new DBMaxIdGenerator instance.

Supported configuration parameters:

Name	optional?	Usage
table	no	name of the table where the id field is stored
column	no	name of the id field

Parameters:

params - configuration parameters

Throws:

IdGenerationException

Method Detail

getNewId

public Object getNewId(DatastoreTransaction ta)
                throws IdGenerationException

Returns a new primary key.

Specified by:

getNewId in class IdGenerator

Parameters:

ta - datastore transaction (context)

Returns:

a new primary key.

Throws:

IdGenerationException - if the generation of the id could not be performed

getNewId

public FeatureId getNewId(MappedFeatureType ft,
                          DatastoreTransaction ta)
                   throws IdGenerationException

Returns a new id for a feature of the given type.

Specified by:

getNewId in class IdGenerator

Parameters:

ft - (mapped) feature type

ta - datastore transaction (context)

Returns:

a new feature id.

Throws:

IdGenerationException - if the generation of the id could not be performed