com.db4o.ext

Interface ObjectCallbacks

public interface ObjectCallbacks

callback methods.

This interface only serves as a list of all available callback methods. Every method is called individually, independantly of implementing this interface.

Using callbacks
Simply implement one or more of the listed methods in your application classes to do tasks before activation, deactivation, delete, new or update, to cancel the action about to be performed and to respond to the performed task.

Callback methods are typically used for:
- cascaded delete
- cascaded update
- cascaded activation
- restoring transient members on instantiation

Callback methods follow regular calling conventions. Methods in superclasses need to be called explicitely.

All method calls are implemented to occur only once, upon one event.

Method Summary

Methods

Modifier and Type	Method and Description
boolean	objectCanActivate(ObjectContainer container) called before an Object is activated.
boolean	objectCanDeactivate(ObjectContainer container) called before an Object is deactivated.
boolean	objectCanDelete(ObjectContainer container) called before an Object is deleted.
boolean	objectCanNew(ObjectContainer container) called before an Object is stored the first time.
boolean	objectCanUpdate(ObjectContainer container) called before a persisted Object is updated.
void	objectOnActivate(ObjectContainer container) called upon activation of an object.
void	objectOnDeactivate(ObjectContainer container) called upon deactivation of an object.
void	objectOnDelete(ObjectContainer container) called after an object was deleted.
void	objectOnNew(ObjectContainer container) called after a new object was stored.
void	objectOnUpdate(ObjectContainer container) called after an object was updated.

Method Detail

objectCanActivate

boolean objectCanActivate(ObjectContainer container)

called before an Object is activated.

Parameters:

container - the ObjectContainer the object is stored in.

Returns:

false to prevent activation.

objectCanDeactivate

boolean objectCanDeactivate(ObjectContainer container)

called before an Object is deactivated.

Parameters:

container - the ObjectContainer the object is stored in.

Returns:

false to prevent deactivation.

objectCanDelete

boolean objectCanDelete(ObjectContainer container)

called before an Object is deleted.

In a client/server setup this callback method will be executed on the server.

Parameters:

container - the ObjectContainer the object is stored in.

Returns:

false to prevent the object from being deleted.

objectCanNew

boolean objectCanNew(ObjectContainer container)

called before an Object is stored the first time.

Parameters:

container - the ObjectContainer is about to be stored to.

Returns:

false to prevent the object from being stored.

objectCanUpdate

boolean objectCanUpdate(ObjectContainer container)

called before a persisted Object is updated.

Parameters:

container - the ObjectContainer the object is stored in.

Returns:

false to prevent the object from being updated.

objectOnActivate

void objectOnActivate(ObjectContainer container)

called upon activation of an object.

Parameters:

container - the ObjectContainer the object is stored in.

objectOnDeactivate

void objectOnDeactivate(ObjectContainer container)

called upon deactivation of an object.

Parameters:

container - the ObjectContainer the object is stored in.

objectOnDelete

void objectOnDelete(ObjectContainer container)

called after an object was deleted.

In a client/server setup this callback method will be executed on the server.

Parameters:

container - the ObjectContainer the object was stored in.

objectOnNew

void objectOnNew(ObjectContainer container)

called after a new object was stored.

Parameters:

container - the ObjectContainer the object is stored to.

objectOnUpdate

void objectOnUpdate(ObjectContainer container)

called after an object was updated.

Parameters:

container - the ObjectContainer the object is stored in.