ObjectChangePolicy (Oracle Fusion Middleware Java API Reference for Oracle TopLink)

All Superinterfaces:

java.io.Serializable

All Known Implementing Classes:

AttributeChangeTrackingPolicy, DeferredChangeDetectionPolicy, ObjectChangeTrackingPolicy
```
public interface ObjectChangePolicy
extends java.io.Serializable
```
INTERNAL: Implementers of ObjectChangePolicy implement the code which computes changes sets for the UnitOfWork commit process. An ObjectChangePolicy is stored on an Object's descriptor.

Author:

Tom Ware

See Also:

DeferredChangeDetectionPolicy, ObjectChangeTrackingPolicy, AttributeChangeTrackingPolicy

Method Summary

Methods
Modifier and Type	Method and Description
`java.lang.Object`	`buildBackupClone(java.lang.Object clone, org.eclipse.persistence.internal.descriptors.ObjectBuilder builder, org.eclipse.persistence.internal.sessions.UnitOfWorkImpl uow)` INTERNAL: Build back up clone.
`org.eclipse.persistence.internal.sessions.ObjectChangeSet`	`calculateChanges(java.lang.Object clone, java.lang.Object backupClone, boolean isNew, org.eclipse.persistence.internal.sessions.UnitOfWorkChangeSet changes, org.eclipse.persistence.internal.sessions.UnitOfWorkImpl unitOfWork, ClassDescriptor descriptor, boolean shouldRaiseEvent)` INTERNAL: CalculateChanges creates a change set for an existing object.
`org.eclipse.persistence.internal.sessions.ObjectChangeSet`	`calculateChangesForExistingObject(java.lang.Object clone, org.eclipse.persistence.internal.sessions.UnitOfWorkChangeSet changes, org.eclipse.persistence.internal.sessions.UnitOfWorkImpl unitOfWork, ClassDescriptor descriptor, boolean shouldRaiseEvent)` INTERNAL: CalculateChanges creates a change set for an existing object.
`org.eclipse.persistence.internal.sessions.ObjectChangeSet`	`calculateChangesForNewObject(java.lang.Object clone, org.eclipse.persistence.internal.sessions.UnitOfWorkChangeSet changes, org.eclipse.persistence.internal.sessions.UnitOfWorkImpl unitOfWork, ClassDescriptor descriptor, boolean shouldRaiseEvent)` INTERNAL: CalculateChanges creates a change set for a new object.
`void`	`clearChanges(java.lang.Object object, org.eclipse.persistence.internal.sessions.UnitOfWorkImpl uow, ClassDescriptor descriptor, boolean forRefresh)` INTERNAL: This is a place holder for reseting the listener on one of the subclasses
`org.eclipse.persistence.internal.sessions.ObjectChangeSet`	`createObjectChangeSetThroughComparison(java.lang.Object clone, java.lang.Object backUp, org.eclipse.persistence.internal.sessions.UnitOfWorkChangeSet changeSet, boolean isNew, org.eclipse.persistence.internal.sessions.AbstractSession session, ClassDescriptor descriptor)` INTERNAL: Create ObjectChangeSet through comparison.
`void`	`dissableEventProcessing(java.lang.Object changeTracker)` INTERNAL: This method is used to disable changetracking temporarily
`void`	`enableEventProcessing(java.lang.Object changeTracker)` INTERNAL: This method is used to enable changetracking temporarily
`void`	`initialize(org.eclipse.persistence.internal.sessions.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(java.lang.Object source, java.lang.String propertyName, java.lang.Object oldValue, java.lang.Object newValue)` INTERNAL: This may cause a property change event to be raised to a listener in the case that a listener exists.
`void`	`revertChanges(java.lang.Object clone, ClassDescriptor descriptor, org.eclipse.persistence.internal.sessions.UnitOfWorkImpl uow, java.util.Map cloneMapping, boolean forRefresh)` INTERNAL: This method is used to revert an object within the unit of work
`void`	`setAggregateChangeListener(java.lang.Object parent, java.lang.Object aggregate, org.eclipse.persistence.internal.sessions.UnitOfWorkImpl uow, ClassDescriptor descriptor, java.lang.String mappingAttribute)` INTERNAL: Assign Changelistener to an aggregate object
`java.beans.PropertyChangeListener`	`setChangeListener(java.lang.Object clone, org.eclipse.persistence.internal.sessions.UnitOfWorkImpl uow, ClassDescriptor descriptor)` INTERNAL: Assign appropriate ChangeListener to PropertyChangeListener based on the policy.
`void`	`setChangeSetOnListener(org.eclipse.persistence.internal.sessions.ObjectChangeSet objectChangeSet, java.lang.Object clone)` INTERNAL: Set the ObjectChangeSet on the Listener, initially used for aggregate support
`boolean`	`shouldCompareExistingObjectForChange(java.lang.Object object, org.eclipse.persistence.internal.sessions.UnitOfWorkImpl unitOfWork, ClassDescriptor descriptor)` INTERNAL: Return true if the Object should be compared, false otherwise.
`void`	`updateListenerForSelfMerge(org.eclipse.persistence.internal.descriptors.changetracking.ObjectChangeListener listener, ForeignReferenceMapping mapping, java.lang.Object source, java.lang.Object target, org.eclipse.persistence.internal.sessions.UnitOfWorkImpl unitOfWork)` INTERNAL: In cases where a relationship with detached or new entities is merged into itself previous changes may have been recorded for the detached/new entity that need to be updated.
`void`	`updateWithChanges(java.lang.Object clone, org.eclipse.persistence.internal.sessions.ObjectChangeSet objectChangeSet, org.eclipse.persistence.internal.sessions.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

calculateChangesForNewObject

org.eclipse.persistence.internal.sessions.ObjectChangeSet calculateChangesForNewObject(java.lang.Object clone,
                                                                                     org.eclipse.persistence.internal.sessions.UnitOfWorkChangeSet changes,
                                                                                     org.eclipse.persistence.internal.sessions.UnitOfWorkImpl unitOfWork,
                                                                                     ClassDescriptor descriptor,
                                                                                     boolean shouldRaiseEvent)

INTERNAL: CalculateChanges creates a change set for a new object.

Parameters:: clone - the Object to compute a change set for; changes - the change set to add changes to; session - the current session; descriptor - the descriptor for this object; shouldRaiseEvent - indicates whether PreUpdate event should be risen (usually true)
Returns:: ObjectChangeSet an object change set describing the changes to this object

calculateChangesForExistingObject

org.eclipse.persistence.internal.sessions.ObjectChangeSet calculateChangesForExistingObject(java.lang.Object clone,
                                                                                          org.eclipse.persistence.internal.sessions.UnitOfWorkChangeSet changes,
                                                                                          org.eclipse.persistence.internal.sessions.UnitOfWorkImpl unitOfWork,
                                                                                          ClassDescriptor descriptor,
                                                                                          boolean shouldRaiseEvent)

INTERNAL: CalculateChanges creates a change set for an existing object.

Parameters:: clone - the Object to compute a change set for; changes - the change set to add changes to; session - the current session; descriptor - the descriptor for this object; shouldRaiseEvent - indicates whether PreUpdate event should be risen (usually true)
Returns:: ObjectChangeSet an object change set describing the changes to this object

calculateChanges

org.eclipse.persistence.internal.sessions.ObjectChangeSet calculateChanges(java.lang.Object clone,
                                                                         java.lang.Object backupClone,
                                                                         boolean isNew,
                                                                         org.eclipse.persistence.internal.sessions.UnitOfWorkChangeSet changes,
                                                                         org.eclipse.persistence.internal.sessions.UnitOfWorkImpl unitOfWork,
                                                                         ClassDescriptor descriptor,
                                                                         boolean shouldRaiseEvent)

INTERNAL: CalculateChanges creates a change set for an existing object.

Parameters:: clone - the object to compute a change set for; backupClone - the object used to compute changes from; isNew - determines if the object is new; changes - the change set to add changes to; session - the current session; descriptor - the descriptor for this object; shouldRaiseEvent - indicates whether PreUpdate event should be risen (usually true)
Returns:: ObjectChangeSet an object change set describing the changes to this object

createObjectChangeSetThroughComparison

org.eclipse.persistence.internal.sessions.ObjectChangeSet createObjectChangeSetThroughComparison(java.lang.Object clone,
                                                                                               java.lang.Object backUp,
                                                                                               org.eclipse.persistence.internal.sessions.UnitOfWorkChangeSet changeSet,
                                                                                               boolean isNew,
                                                                                               org.eclipse.persistence.internal.sessions.AbstractSession session,
                                                                                               ClassDescriptor descriptor)

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

updateListenerForSelfMerge

void updateListenerForSelfMerge(org.eclipse.persistence.internal.descriptors.changetracking.ObjectChangeListener listener,
                              ForeignReferenceMapping mapping,
                              java.lang.Object source,
                              java.lang.Object target,
                              org.eclipse.persistence.internal.sessions.UnitOfWorkImpl unitOfWork)

INTERNAL: In cases where a relationship with detached or new entities is merged into itself previous changes may have been recorded for the detached/new entity that need to be updated.

dissableEventProcessing
```
void dissableEventProcessing(java.lang.Object changeTracker)
```
INTERNAL: This method is used to disable changetracking temporarily

enableEventProcessing
```
void enableEventProcessing(java.lang.Object changeTracker)
```
INTERNAL: This method is used to enable changetracking temporarily

raiseInternalPropertyChangeEvent

void raiseInternalPropertyChangeEvent(java.lang.Object source,
                                    java.lang.String propertyName,
                                    java.lang.Object oldValue,
                                    java.lang.Object newValue)

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

revertChanges

void revertChanges(java.lang.Object clone,
                 ClassDescriptor descriptor,
                 org.eclipse.persistence.internal.sessions.UnitOfWorkImpl uow,
                 java.util.Map cloneMapping,
                 boolean forRefresh)

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

clearChanges

void clearChanges(java.lang.Object object,
                org.eclipse.persistence.internal.sessions.UnitOfWorkImpl uow,
                ClassDescriptor descriptor,
                boolean forRefresh)

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

updateWithChanges

void updateWithChanges(java.lang.Object clone,
                     org.eclipse.persistence.internal.sessions.ObjectChangeSet objectChangeSet,
                     org.eclipse.persistence.internal.sessions.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.

shouldCompareExistingObjectForChange
```
boolean shouldCompareExistingObjectForChange(java.lang.Object object,
                                           org.eclipse.persistence.internal.sessions.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(java.lang.Object parent,
                              java.lang.Object aggregate,
                              org.eclipse.persistence.internal.sessions.UnitOfWorkImpl uow,
                              ClassDescriptor descriptor,
                              java.lang.String mappingAttribute)

INTERNAL: Assign Changelistener to an aggregate object

setChangeListener

java.beans.PropertyChangeListener setChangeListener(java.lang.Object clone,
                                                  org.eclipse.persistence.internal.sessions.UnitOfWorkImpl uow,
                                                  ClassDescriptor descriptor)

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

setChangeSetOnListener

void setChangeSetOnListener(org.eclipse.persistence.internal.sessions.ObjectChangeSet objectChangeSet,
                          java.lang.Object clone)

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

buildBackupClone

java.lang.Object buildBackupClone(java.lang.Object clone,
                                org.eclipse.persistence.internal.descriptors.ObjectBuilder builder,
                                org.eclipse.persistence.internal.sessions.UnitOfWorkImpl uow)

INTERNAL: Build back up clone.

initialize

void initialize(org.eclipse.persistence.internal.sessions.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

Interface ObjectChangePolicy