org.castor.persist

Class ObjectTracker

java.lang.Object

org.castor.persist.ObjectTracker

public final class ObjectTracker
extends Object

A transaction records all objects accessed during the lifetime of the transaction in this record (queries and created). This information, stored on a per-object basis within the ObjectTracker, covers the database engine used to persist the object, the object's OID, the object itself, and whether the object has been deleted in this transaction, created in this transaction. Sidenote: Objects identified as read only are not updated when the transaction commits.

Since:

0.9.9

Version:

$Revision: 7951 $ $Date: 2006-04-29 09:15:50 -0600 (Sat, 29 Apr 2006) $

Author:

Ralf Joachim, Werner Guttmann, Gregory Block

Constructor Summary

Constructors

Constructor and Description
ObjectTracker()

Method Summary

Methods

Modifier and Type	Method and Description
String	allObjectStates()
void	clear() Reset ObjectTracker's state.
ClassMolder	getMolderForObject(Object o) Retrieve the ClassMolder associated with a specific object.
Object	getObjectForOID(LockEngine engine, OID oid, boolean allowReadOnly) Retrieve the object for a given OID.
Collection	getObjectsWithCreatingStateSortedByLowestMolderPriority() Retrieve the list of 'creating' objects (to be created), sorted in the order they should be created.
Collection	getObjectsWithDeletedStateSortedByHighestMolderPriority() Retrieve the list of 'deleted' objects, sorted in the order they should be deleted.
Collection	getObjectsWithUpdateCacheNeededState()
OID	getOIDForObject(Object o)
Collection	getReadOnlyObjects() Retrieve the list of all read-only objects being tracked.
Collection	getReadWriteObjects() Retrieve the list of all read-write objects being tracked.
boolean	isCreated(Object o)
boolean	isCreating(Object o)
boolean	isDeleted(Object o)
boolean	isReadOnly(Object o)
boolean	isReadWrite(Object object) Returns true if the specified object is tracked as a read-write object.
boolean	isTracking(Object object) Determine whether an object is being tracked within this tracking manager.
boolean	isUpdateCacheNeeded(Object object) Returns true if the cache needs to be updated for the given object.
boolean	isUpdatePersistNeeded(Object object) Returns true if the given object needs to be written to the persistence store.
void	markCreated(Object object)
void	markCreating(Object object)
void	markDeleted(Object object)
void	markReadOnly(Object o)
void	markUpdateCacheNeeded(Object object)
void	markUpdatePersistNeeded(Object object)
String	objectStateToString(Object obj) Returns the object's state.
int	readOnlySize()
int	readWriteSize()
void	removeOIDForObject(LockEngine engine, OID oid) For a given lockengine and OID, remove references to an object in the maps.
void	setOIDForObject(Object obj, LockEngine engine, OID oid) For a given lockengine and OID, set the object in the maps.
void	trackObject(ClassMolder molder, OID oid, Object object)
void	trackOIDChange(Object obj, LockEngine engine, OID oldoid, OID newoid) Record changes to an OID by re-tracking the OID information.
void	unmarkAllDeleted()
void	unmarkDeleted(Object object)
void	unmarkReadOnly(Object o)
void	unmarkUpdateCacheNeeded(Object object)
void	unmarkUpdatePersistNeeded(Object object)
void	untrackObject(Object object)

Methods inherited from class java.lang.Object

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

Constructor Detail

ObjectTracker

public ObjectTracker()

Method Detail

getObjectForOID

public Object getObjectForOID(LockEngine engine,
                     OID oid,
                     boolean allowReadOnly)

Retrieve the object for a given OID.

Parameters:

engine - Lock engine mapped to oid

oid - Object id specified

allowReadOnly - Allow (or ignore, if false) read-only objects to be returned.

Returns:

The object associated with this oid.

isReadWrite

public boolean isReadWrite(Object object)

Returns true if the specified object is tracked as a read-write object.

Parameters:

object - Object instance for which it should be determined whether it's tracked as read-write object

Returns:

True if the specified object is tracked as a read-write object

unmarkAllDeleted

public void unmarkAllDeleted()

clear

public void clear()

Reset ObjectTracker's state.

isUpdateCacheNeeded

public boolean isUpdateCacheNeeded(Object object)

Returns true if the cache needs to be updated for the given object.

Parameters:

object - An object instance

Returns:

true if the cache needs to be updated; false, otherwise.

isUpdatePersistNeeded

public boolean isUpdatePersistNeeded(Object object)

Returns true if the given object needs to be written to the persistence store.

Parameters:

object - An object instance

Returns:

true if the object needs to be written to the persistence store

markUpdateCacheNeeded

public void markUpdateCacheNeeded(Object object)

unmarkUpdateCacheNeeded

public void unmarkUpdateCacheNeeded(Object object)

getObjectsWithUpdateCacheNeededState

public Collection getObjectsWithUpdateCacheNeededState()

markUpdatePersistNeeded

public void markUpdatePersistNeeded(Object object)

unmarkUpdatePersistNeeded

public void unmarkUpdatePersistNeeded(Object object)

markCreating

public void markCreating(Object object)
                  throws PersistenceException

Throws:

PersistenceException

markCreated

public void markCreated(Object object)

markDeleted

public void markDeleted(Object object)

unmarkDeleted

public void unmarkDeleted(Object object)

isTracking

public boolean isTracking(Object object)

Determine whether an object is being tracked within this tracking manager.

Parameters:

object - The object for which it should be determined whether it is tracked.

Returns:

True if the object specified is tracked; false otherwise

trackOIDChange

public void trackOIDChange(Object obj,
                  LockEngine engine,
                  OID oldoid,
                  OID newoid)

Record changes to an OID by re-tracking the OID information. When an object's OID can change, ensure that the object is retracked.

Parameters:

obj - The object to record a tracking change for.

engine - The engine which is responsible for the old and new OID

oldoid - The old oid.

newoid - The new oid.

setOIDForObject

public void setOIDForObject(Object obj,
                   LockEngine engine,
                   OID oid)

For a given lockengine and OID, set the object in the maps. Note that an OID can only be accessed via the LockManager which manages it.

Parameters:

obj - The object to track

engine - The engine to which the OID belongs

oid - The OID of the object to track

removeOIDForObject

public void removeOIDForObject(LockEngine engine,
                      OID oid)

For a given lockengine and OID, remove references to an object in the maps. This eliminates both the engine->oid->object and the object->oid.

Parameters:

engine - The engine to stop tracking the OID for

oid - The oid of the object to stop tracking on.

isCreating

public boolean isCreating(Object o)

isCreated

public boolean isCreated(Object o)

isDeleted

public boolean isDeleted(Object o)

getMolderForObject

public ClassMolder getMolderForObject(Object o)

Retrieve the ClassMolder associated with a specific object.

Parameters:

o - Object instance the associated ClassMolder should be retrieved.

Returns:

The ClassMolder instance associated with the Object instance specified.

getReadWriteObjects

public Collection getReadWriteObjects()

Retrieve the list of all read-write objects being tracked.

Returns:

List of all read-write objects being currently tracked.

getReadOnlyObjects

public Collection getReadOnlyObjects()

Retrieve the list of all read-only objects being tracked.

Returns:

List of all read-only objects being currently tracked

getObjectsWithCreatingStateSortedByLowestMolderPriority

public Collection getObjectsWithCreatingStateSortedByLowestMolderPriority()

Retrieve the list of 'creating' objects (to be created), sorted in the order they should be created.

Returns:

List of objects to be created, sorted in the order they should be created.

getObjectsWithDeletedStateSortedByHighestMolderPriority

public Collection getObjectsWithDeletedStateSortedByHighestMolderPriority()

Retrieve the list of 'deleted' objects, sorted in the order they should be deleted.

Returns:

List of 'deleted' objects, sorted in the order they should be deleted.

trackObject

public void trackObject(ClassMolder molder,
               OID oid,
               Object object)

untrackObject

public void untrackObject(Object object)

getOIDForObject

public OID getOIDForObject(Object o)

isReadOnly

public boolean isReadOnly(Object o)

markReadOnly

public void markReadOnly(Object o)

unmarkReadOnly

public void unmarkReadOnly(Object o)

readOnlySize

public int readOnlySize()

readWriteSize

public int readWriteSize()

allObjectStates

public String allObjectStates()

objectStateToString

public String objectStateToString(Object obj)

Returns the object's state.

Parameters:

obj - Object for which its state should be output.

Returns:

The state of the object specified