atg.service.idgen
Class PersistentIdGenerator

java.lang.Object
  atg.nucleus.logging.VariableArgumentApplicationLoggingImpl
      atg.nucleus.GenericService
          atg.service.idgen.AbstractSequentialIdGenerator
              atg.service.idgen.PersistentIdGenerator

All Implemented Interfaces:

atg.naming.AbsoluteNameable, NameContextBindingListener, NameContextElement, atg.naming.NameContextParentable, NameResolver, AdminableService, atg.nucleus.Configured, ApplicationLogging, atg.nucleus.logging.ApplicationLoggingSender, atg.nucleus.logging.TraceApplicationLogging, VariableArgumentApplicationLogging, ComponentNameResolver, Service, ServiceListener, IdGenerator, java.util.EventListener

Direct Known Subclasses:

FileIdGenerator, SQLIdGenerator

public abstract class PersistentIdGenerator
extends AbstractSequentialIdGenerator
implements IdGenerator

An IdGenerator that gives out ids suitable for use with persistent objects. The ids are reserved in batches from some a persistent data store. The ids generated generally sequential and strictly increasing. A PersistentIdGenerator will not avoid ever giving out the same id twice for a given IdSpace, even across restarts of the JVM. This class reserves batches of ids from the data store and doles them out one at a time. Thus the ids given out are generally sequential and strictly increasing. Subclasses should indicate whether or not they are safe to use in a distributed system.

See Also:

IdGenerator

Field Summary

static java.lang.String	CLASS_VERSION Class version string
protected static java.lang.String	ERR_ADD_BAD_STATE
protected static java.lang.String	ERR_ADD_NULL_SPACE
protected static java.lang.String	ERR_READING_BOOTSTRAP_SPACES
protected static int	STATE_ERROR
protected static int	STATE_INITIALIZING
protected static int	STATE_NEW
protected static int	STATE_RUNNING
protected static java.lang.String	WARN_PICKING_DEFAULT

Fields inherited from class atg.service.idgen.AbstractSequentialIdGenerator

ERR_BAD_SPACE, ERR_ROLLBACK, ERR_UNSUPPORTED, mSpaces, RESOURCE_BUNDLE_NAME, sResourceBundle

Fields inherited from class atg.nucleus.GenericService

SERVICE_INFO_KEY

Fields inherited from interface atg.nucleus.logging.TraceApplicationLogging

DEFAULT_LOG_TRACE_STATUS

Fields inherited from interface atg.nucleus.logging.ApplicationLogging

DEFAULT_LOG_DEBUG_STATUS, DEFAULT_LOG_ERROR_STATUS, DEFAULT_LOG_INFO_STATUS, DEFAULT_LOG_WARNING_STATUS

Constructor Summary

PersistentIdGenerator()

Method Summary

boolean	addIdSpace(IdSpace pSpace) Add an id space to the id generator.
protected abstract boolean	addPersistentIdSpace(IdSpace pSpace) Add id space to the data store.
atg.xml.XMLFile	getInitialIdSpaces() Get property initialIdSpaces
boolean	getLoadInitialIdSpacesAtStartup() Get property loadInitialIdSpacesAtStartup.
javax.transaction.TransactionManager	getTransactionManager() Get property TransactionManager
atg.xml.tools.XMLToolsFactory	getXMLToolsFactory() Get property XMLToolsFactory
void	initialize() Initialize the generator.
protected abstract void	initializeIdSpaces() Initialize the id spaces from the data store.
void	removeAllIdSpaces() Remove all id spaces from the id generator.
boolean	removeIdSpace(IdSpace pSpace) Remove an id space from the id generator.
protected abstract void	reserveSeeds(IdSpace pSpace) Reserve a batch of seeds for the specified id space and update the id space itself with the new seed information.
void	setInitialIdSpaces(atg.xml.XMLFile pInitialIdSpaces) Set property initialIdSpaces
void	setLoadInitialIdSpacesAtStartup(boolean pLoadInitialIdSpacesAtStartup) Set property loadInitialIdSpacesAtStartup.
void	setTransactionManager(javax.transaction.TransactionManager pTransactionManager) Set property TransactionManager
void	setXMLToolsFactory(atg.xml.tools.XMLToolsFactory pXMLToolsFactory) Set property XMLToolsFactory

Methods inherited from class atg.service.idgen.AbstractSequentialIdGenerator

doStartService, format, format, format, format, generateLongId, generateLongId, generateStringId, generateStringId, getAutoCreate, getBundle, getDefaultIdSpace, getDefaultIdSpaceName, getIdSpace, getIdSpaces, getResourceBundleName, isAutoCreate, postGenerateLongId, postGenerateStringId, setAutoCreate, setDefaultIdSpace, setDefaultIdSpaceName, setHighWaterMark, toString

Methods inherited from class atg.nucleus.GenericService

addLogListener, createAdminServlet, doStopService, getAbsoluteName, getAdminServlet, getAdminServletOutputStreamEncoding, getLoggingForVlogging, getLogListenerCount, getLogListeners, getName, getNameContext, getNucleus, getRoot, getServiceConfiguration, getServiceInfo, isAdminServletUseServletOutputStream, isLoggingDebug, isLoggingError, isLoggingInfo, isLoggingTrace, isLoggingWarning, isRunning, logDebug, logDebug, logDebug, logError, logError, logError, logInfo, logInfo, logInfo, logTrace, logTrace, logTrace, logWarning, logWarning, logWarning, nameContextElementBound, nameContextElementUnbound, removeLogListener, reResolveThis, resolveName, resolveName, resolveName, resolveName, sendLogEvent, setAdminServletOutputStreamEncoding, setAdminServletUseServletOutputStream, setLoggingDebug, setLoggingError, setLoggingInfo, setLoggingTrace, setLoggingWarning, setNucleus, setServiceInfo, startService, stopService

Methods inherited from class atg.nucleus.logging.VariableArgumentApplicationLoggingImpl

vlogDebug, vlogDebug, vlogDebug, vlogDebug, vlogDebugTrace, vlogError, vlogError, vlogError, vlogError, vlogInfo, vlogInfo, vlogInfo, vlogInfo, vlogTrace, vlogTrace, vlogTrace, vlogTrace, vlogWarning, vlogWarning, vlogWarning, vlogWarning

Methods inherited from class java.lang.Object

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

Methods inherited from interface atg.service.idgen.IdGenerator

generateLongId, generateLongId, generateStringId, generateStringId, getAutoCreate, getDefaultIdSpace, getIdSpace, getIdSpaces, isAutoCreate, setAutoCreate

Field Detail

CLASS_VERSION

public static java.lang.String CLASS_VERSION

Class version string

STATE_NEW

protected static int STATE_NEW

STATE_INITIALIZING

protected static int STATE_INITIALIZING

STATE_RUNNING

protected static int STATE_RUNNING

STATE_ERROR

protected static int STATE_ERROR

WARN_PICKING_DEFAULT

protected static java.lang.String WARN_PICKING_DEFAULT

ERR_READING_BOOTSTRAP_SPACES

protected static java.lang.String ERR_READING_BOOTSTRAP_SPACES

ERR_ADD_NULL_SPACE

protected static java.lang.String ERR_ADD_NULL_SPACE

ERR_ADD_BAD_STATE

protected static java.lang.String ERR_ADD_BAD_STATE

Constructor Detail

PersistentIdGenerator

public PersistentIdGenerator()

Method Detail

setTransactionManager

public void setTransactionManager(javax.transaction.TransactionManager pTransactionManager)

Set property TransactionManager

Parameters:

pTransactionManager - new value to set

getTransactionManager

public javax.transaction.TransactionManager getTransactionManager()

Get property TransactionManager

Returns:

TransactionManager

setXMLToolsFactory

public void setXMLToolsFactory(atg.xml.tools.XMLToolsFactory pXMLToolsFactory)

Set property XMLToolsFactory

Parameters:

pXMLToolsFactory - new value to set

getXMLToolsFactory

public atg.xml.tools.XMLToolsFactory getXMLToolsFactory()

Get property XMLToolsFactory

Returns:

XMLToolsFactory

setInitialIdSpaces

public void setInitialIdSpaces(atg.xml.XMLFile pInitialIdSpaces)

Set property initialIdSpaces

Parameters:

pInitialIdSpaces - new value to set

getInitialIdSpaces

public atg.xml.XMLFile getInitialIdSpaces()

Get property initialIdSpaces

Returns:

initialIdSpaces

setLoadInitialIdSpacesAtStartup

public void setLoadInitialIdSpacesAtStartup(boolean pLoadInitialIdSpacesAtStartup)

Set property loadInitialIdSpacesAtStartup. This is if true the XML file specified by the initialIdSpaces property is loaded at startup. If false the XML file is only loaded when no persistent ids are found in the DB. The default is true.

Parameters:

pLoadInitialIdSpacesAtStartup - new value to set

getLoadInitialIdSpacesAtStartup

public boolean getLoadInitialIdSpacesAtStartup()

Get property loadInitialIdSpacesAtStartup. If this is true the XML file specified by the initialIdSpaces property is loaded at startup. If false the XML file is only loaded when no persistent ids are found in the DB. The default is true.

Returns:

loadInitialIdSpacesAtStartup

initialize

public void initialize()
                throws IdGeneratorException

Initialize the generator. This method must be called before attempting to generate ids. This method runs in its own transaction. Any existing transaction context is suspended and then resumed.

Specified by:

initialize in interface IdGenerator

Overrides:

initialize in class AbstractSequentialIdGenerator

Throws:

IdGeneratorException - if there is an error initializing. If initialization was unsuccessful the IdGeneratorException may have a source exception which is a chain of all of the exceptions encountered during the attempt to initialize

reserveSeeds

protected abstract void reserveSeeds(IdSpace pSpace)
                              throws IdGeneratorException

Reserve a batch of seeds for the specified id space and update the id space itself with the new seed information. This method is called when the current batch of seeds has been used up.

Parameters:

pSpace - id space to reserve seeds in, cannot be null

Throws:

IdGeneratorException - if there is a problem reserving the seeds

initializeIdSpaces

protected abstract void initializeIdSpaces()
                                    throws IdGeneratorException

Initialize the id spaces from the data store. This method is called by initialize.

Throws:

IdGeneratorException

addIdSpace

public boolean addIdSpace(IdSpace pSpace)
                   throws IdGeneratorException

Add an id space to the id generator. The id space must not be null.

Specified by:

addIdSpace in interface IdGenerator

Overrides:

addIdSpace in class AbstractSequentialIdGenerator

Parameters:

pSpace - space to add, cannot be null

Returns:

true if the space is added, or false if a space with the same name already exists in this id generator or there was a problem adding it.

Throws:

IdGeneratorException - if there is trouble adding the space

addPersistentIdSpace

protected abstract boolean addPersistentIdSpace(IdSpace pSpace)
                                         throws IdGeneratorException

Add id space to the data store. Subclasses implement this.

Parameters:

pSpace - space to add, will not be null

Throws:

IdGeneratorException

removeIdSpace

public boolean removeIdSpace(IdSpace pSpace)
                      throws IdGeneratorException

Remove an id space from the id generator. This is not yet supported for persistent id generators.

Specified by:

removeIdSpace in interface IdGenerator

Overrides:

removeIdSpace in class AbstractSequentialIdGenerator

Parameters:

pSpace - space to remove, cannot be null

Returns:

true if the space is removed, or false if it is not known to this id generator

Throws:

IdGeneratorException - not yet supported

removeAllIdSpaces

public void removeAllIdSpaces()
                       throws IdGeneratorException

Remove all id spaces from the id generator. This is not yet supported for persistent id generators.

Specified by:

removeAllIdSpaces in interface IdGenerator

Overrides:

removeAllIdSpaces in class AbstractSequentialIdGenerator

Throws:

IdGeneratorException - not yet supported