org.apache.ojb.broker.util.sequence
Class SequenceManagerNextValImpl

java.lang.Object
  org.apache.ojb.broker.util.sequence.AbstractSequenceManager
      org.apache.ojb.broker.util.sequence.SequenceManagerNextValImpl

All Implemented Interfaces:

SequenceManager

Direct Known Subclasses:

SequenceManagerSeqHiLoImpl

public class SequenceManagerNextValImpl
extends AbstractSequenceManager

This SequenceManager implementation uses database sequence key generation (e.g supported by Oracle, SAP DB, PostgreSQL, ...). This class is responsible for creating new unique ID's.
It is possible to define a sequence-name field-descriptor attribute in the repository file. If such an attribute was not found, the implementation build an extent aware sequence name by its own.
Keep in mind when define a sequence name, that you are responsible to be aware of extents, that is: if you ask for an uid for an interface with several implementor classes, or a baseclass with several subclasses the returned uid have to be unique accross all tables representing objects of the extent in question. Thus you have to use the same sequence-name for all extents.

Implementation configuration properties:

Property Key	Property Values
autoNaming	Default was 'true'. If set 'true' OJB try to build a sequence name automatic if none found in field-descriptor and set this generated name as sequence-name in field-descriptor. If set 'false' OJB throws an exception if none sequence name was found in field-descriptor, ditto OJB does NOT try to create a database sequence entry when for given sequence name no database sequence could be found.

Limitations:

• none

Version:

$Id: SequenceManagerNextValImpl.java,v 1.1 2007-08-24 22:17:29 ewestfal Exp $

Author:

Edson Carlos Ericksson Richter, Rajeev Kaul, Thomas Mahler, Armin Waibel

Field Summary

private Logger

log

Fields inherited from class org.apache.ojb.broker.util.sequence.AbstractSequenceManager

GLOBAL_SEQUENCE_NAME, PROPERTY_AUTO_NAMING

Constructor Summary

SequenceManagerNextValImpl(PersistenceBroker broker)

Method Summary

protected long	buildNextSequence(ClassDescriptor cld, String sequenceName)
protected void	createSequence(ClassDescriptor cld, String sequenceName)
protected int	getUniqueId(FieldDescriptor field) returns a unique int value for class clazz and field fieldName.
protected long	getUniqueLong(FieldDescriptor field) returns a unique long value for class clazz and field fieldName.

Methods inherited from class org.apache.ojb.broker.util.sequence.AbstractSequenceManager

afterStore, calculateSequenceName, getBrokerForClass, getConfigurationProperties, getConfigurationProperty, getPlatform, getUniqueValue, setConfigurationProperties, setConfigurationProperty, setReferenceFKs, useAutoNaming

Methods inherited from class java.lang.Object

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

Field Detail

log

private Logger log

Constructor Detail

SequenceManagerNextValImpl

public SequenceManagerNextValImpl(PersistenceBroker broker)

Method Detail

getUniqueId

protected int getUniqueId(FieldDescriptor field)
                   throws SequenceManagerException

returns a unique int value for class clazz and field fieldName. the returned number is unique accross all tables in the extent of clazz.

Throws:

SequenceManagerException

getUniqueLong

protected long getUniqueLong(FieldDescriptor field)
                      throws SequenceManagerException

returns a unique long value for class clazz and field fieldName. the returned number is unique accross all tables in the extent of clazz.

Specified by:

getUniqueLong in class AbstractSequenceManager

Throws:

SequenceManagerException

buildNextSequence

protected long buildNextSequence(ClassDescriptor cld,
                                 String sequenceName)
                          throws Exception

Throws:

Exception

createSequence

protected void createSequence(ClassDescriptor cld,
                              String sequenceName)
                       throws Exception

Throws:

Exception