oracle.toplink.essentials.descriptors.changetracking

Interface ObjectChangePolicy

All Superinterfaces:

Serializable

All Known Implementing Classes:

DeferredChangeDetectionPolicy

public interface ObjectChangePolicy
extends Serializable

INTERNAL: Implementers of ObjectChangePolicy implement the code which computes changes sets for TopLink's UnitOfWork commit process. An ObjectChangePolicy is stored on an Object's descriptor.

Author:

Tom Ware

See Also:

DeferredChangeDetectionPolicy, ObjectChangeTrackingPolicy, AttributeChangeTrackingPolicy

Method Summary

Modifier and Type	Method and Description
Object	buildBackupClone(Object clone, ObjectBuilder builder, UnitOfWorkImpl uow) INTERNAL: Build back up clone.
ObjectChangeSet	calculateChanges(Object clone, Object backUp, UnitOfWorkChangeSet changes, AbstractSession session, ClassDescriptor descriptor, boolean shouldRiseEvent) INTERNAL: calculateChanges creates a change set for a particular object
void	clearChanges(Object object, UnitOfWorkImpl uow, ClassDescriptor descriptor) INTERNAL: This is a place holder for reseting the listener on one of the subclasses
ObjectChangeSet	createObjectChangeSetThroughComparison(Object clone, Object backUp, UnitOfWorkChangeSet changeSet, boolean isNew, AbstractSession session, ClassDescriptor descriptor) INTERNAL: Create ObjectChangeSet through comparison.
void	dissableEventProcessing(Object changeTracker) INTERNAL: This method is used to dissable changetracking temporarily
void	enableEventProcessing(Object changeTracker) INTERNAL: This method is used to enable changetracking temporarily
void	initialize(AbstractSession session, ClassDescriptor descriptor) INTERNAL: initialize the Policy
boolean	isAttributeChangeTrackingPolicy() Used to track instances of the change policies without doing an instance of check
boolean	isDeferredChangeDetectionPolicy() Used to track instances of the change policies without doing an instance of check
boolean	isObjectChangeTrackingPolicy() Used to track instances of the change policies without doing an instance of check
void	raiseInternalPropertyChangeEvent(Object source, String propertyName, Object oldValue, Object newValue) INTERNAL: This may cause a property change event to be raised to a listner in the case that a listener exists.
void	revertChanges(Object clone, ClassDescriptor descriptor, UnitOfWorkImpl uow, IdentityHashtable cloneMapping) INTERNAL: This method is used to revert an object within the unit of work
void	setAggregateChangeListener(Object parent, Object aggregate, UnitOfWorkImpl uow, ClassDescriptor descriptor, String mappingAttribute) INTERNAL: Assign Changelistner to an aggregate object
void	setChangeListener(Object clone, UnitOfWorkImpl uow, ClassDescriptor descriptor) INTERNAL: Assign appropriate ChangeListener to PropertyChangeListener based on the policy.
void	setChangeSetOnListener(ObjectChangeSet objectChangeSet, Object clone) INTERNAL: Set the ObjectChangeSet on the Listener, initially used for aggregate support
boolean	shouldCompareForChange(Object object, UnitOfWorkImpl unitOfWork, ClassDescriptor descriptor) INTERNAL: Return true if the Object should be compared, false otherwise.
void	updateWithChanges(Object clone, ObjectChangeSet objectChangeSet, UnitOfWorkImpl uow, ClassDescriptor descriptor) INTERNAL: This method is used internally to rest the policies back to original state This is used when the clones are to be reused.

Method Detail

calculateChanges

ObjectChangeSet calculateChanges(Object clone,
                                 Object backUp,
                                 UnitOfWorkChangeSet changes,
                                 AbstractSession session,
                                 ClassDescriptor descriptor,
                                 boolean shouldRiseEvent)

INTERNAL: calculateChanges creates a change set for a particular object

Parameters:

clone - the Object to compute a change set for

backUp - the old version of the object to use for comparison

changes - the change set to add changes to

session - the current session

descriptor - the descriptor for this object

shouldRiseEvent - indicates whether PreUpdate event should be risen (usually true)

Returns:

oracle.toplink.essentials.changesets.ObjectChangeSet an object change set describing the changes to this object

createObjectChangeSetThroughComparison

ObjectChangeSet createObjectChangeSetThroughComparison(Object clone,
                                                       Object backUp,
                                                       UnitOfWorkChangeSet changeSet,
                                                       boolean isNew,
                                                       AbstractSession session,
                                                       ClassDescriptor descriptor)

INTERNAL: Create ObjectChangeSet through comparison. Used in cases where we need to force change calculation (ie aggregates)

dissableEventProcessing

void dissableEventProcessing(Object changeTracker)

INTERNAL: This method is used to dissable changetracking temporarily

enableEventProcessing

void enableEventProcessing(Object changeTracker)

INTERNAL: This method is used to enable changetracking temporarily

raiseInternalPropertyChangeEvent

void raiseInternalPropertyChangeEvent(Object source,
                                      String propertyName,
                                      Object oldValue,
                                      Object newValue)

INTERNAL: This may cause a property change event to be raised to a listner in the case that a listener exists. If there is no listener then this call is a no-op

revertChanges

void revertChanges(Object clone,
                   ClassDescriptor descriptor,
                   UnitOfWorkImpl uow,
                   IdentityHashtable cloneMapping)

INTERNAL: This method is used to revert an object within the unit of work

clearChanges

void clearChanges(Object object,
                  UnitOfWorkImpl uow,
                  ClassDescriptor descriptor)

INTERNAL: This is a place holder for reseting the listener on one of the subclasses

updateWithChanges

void updateWithChanges(Object clone,
                       ObjectChangeSet objectChangeSet,
                       UnitOfWorkImpl uow,
                       ClassDescriptor descriptor)

INTERNAL: This method is used internally to rest the policies back to original state This is used when the clones are to be reused.

shouldCompareForChange

boolean shouldCompareForChange(Object object,
                               UnitOfWorkImpl unitOfWork,
                               ClassDescriptor descriptor)

INTERNAL: Return true if the Object should be compared, false otherwise. This method is implemented to allow run time determination of whether a change set should be computed for an object. In general, calculateChanges() will only be executed in a UnitOfWork if this method returns true.

Parameters:

object - the object that will be compared

unitOfWork - the active unitOfWork

descriptor - the descriptor for the current object

setAggregateChangeListener

void setAggregateChangeListener(Object parent,
                                Object aggregate,
                                UnitOfWorkImpl uow,
                                ClassDescriptor descriptor,
                                String mappingAttribute)

INTERNAL: Assign Changelistner to an aggregate object

setChangeListener

void setChangeListener(Object clone,
                       UnitOfWorkImpl uow,
                       ClassDescriptor descriptor)

INTERNAL: Assign appropriate ChangeListener to PropertyChangeListener based on the policy.

setChangeSetOnListener

void setChangeSetOnListener(ObjectChangeSet objectChangeSet,
                            Object clone)

INTERNAL: Set the ObjectChangeSet on the Listener, initially used for aggregate support

buildBackupClone

Object buildBackupClone(Object clone,
                        ObjectBuilder builder,
                        UnitOfWorkImpl uow)

INTERNAL: Build back up clone.

initialize

void initialize(AbstractSession session,
                ClassDescriptor descriptor)

INTERNAL: initialize the Policy

isDeferredChangeDetectionPolicy

boolean isDeferredChangeDetectionPolicy()

Used to track instances of the change policies without doing an instance of check

isObjectChangeTrackingPolicy

boolean isObjectChangeTrackingPolicy()

Used to track instances of the change policies without doing an instance of check

isAttributeChangeTrackingPolicy

boolean isAttributeChangeTrackingPolicy()

Used to track instances of the change policies without doing an instance of check