org.deegree.io.datastore.idgenerator
Class IdGenerator

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

Direct Known Subclasses:

DBMaxIdGenerator, DBSeqIdGenerator, ParentIDGenerator, UUIDGenerator

public abstract class IdGenerator
extends Object

Abstract base class for generators that are used to create primary keys (especially FeatureIds).

Version:

$Revision: 18195 $, $Date: 2009-06-18 17:55:39 +0200 (Thu, 18 Jun 2009) $

Author:

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

Field Summary

protected MappedFeatureType	ft MappedFeatureType that this generator is bound to.
protected Properties	params Configuration properties.
static String	TYPE_UUID Default generator type based on UUIDs.

Constructor Summary

protected

IdGenerator(Properties params) Creates a new IdGenerator instance.

Method Summary

static IdGenerator	getInstance(String type, Properties params) Returns a concrete IdGenerator instance which is identified by the given type code.
abstract Object	getNewId(DatastoreTransaction ta) Returns a new primary key.
abstract FeatureId	getNewId(MappedFeatureType ft, DatastoreTransaction ta) Returns a new id for a feature of the given type.

Methods inherited from class java.lang.Object

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

Field Detail

TYPE_UUID

public static String TYPE_UUID

Default generator type based on UUIDs.

params

protected Properties params

Configuration properties.

ft

protected MappedFeatureType ft

MappedFeatureType that this generator is bound to.

Constructor Detail

IdGenerator

protected IdGenerator(Properties params)

Creates a new IdGenerator instance.

Parameters:

params - configuration parameters

Method Detail

getNewId

public abstract Object getNewId(DatastoreTransaction ta)
                         throws IdGenerationException

Returns a new primary key.

Parameters:

ta - datastore transaction (context)

Returns:

a new primary key.

Throws:

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

getNewId

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

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

Parameters:

ft - feature type

ta - datastore transaction (context)

Returns:

a new feature id.

Throws:

IdGenerationException

getInstance

public static final IdGenerator getInstance(String type,
                                            Properties params)

Returns a concrete IdGenerator instance which is identified by the given type code.

Parameters:

type - type code

params - initialization parameters for the IdGenerator

Returns:

concrete IdGenerator instance