Package 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 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.