Package it.polimi.ingsw.server.event_sourcing

Class Aggregate

java.lang.Object

it.polimi.ingsw.server.event_sourcing.Aggregate

Direct Known Subclasses:

GameState

public abstract class Aggregate
extends Object

Field Summary

Fields

Modifier and Type	Field	Description
final Date	created
UUID	id
static EventsRepository	repository
int	version

Constructor Summary

Constructors

Constructor	Description
Aggregate()
Aggregate(UUID uuid)

Method Summary

Modifier and Type	Method	Description
void	apply(Event event)	Applies an event, given the Event to apply This method will call using reflection the appropriate handler that manage the event
void	createSnapshot()	Generates the snapshot and saves the Aggregate updated information to the repository
Aggregate	getCurrentState()	Restore the aggregate and return the most updated version of the aggregate For doing so, it reconstructs the aggregate from the snapshot and applies the stack of events
static Aggregate	loadFromUuid(UUID uuid)	Returns the updated aggregate based on the UUID
Aggregate	rollback()	Recreates the aggregate based on the last snapshot, deletes all the events vit aggregate version > snapshot version

Methods inherited from class java.lang.Object

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

Field Details

id

public UUID id

created

public final Date created

repository

public static EventsRepository repository

version

public int version

Constructor Details

Aggregate

public Aggregate()

Aggregate

public Aggregate(UUID uuid)

Method Details

loadFromUuid

public static Aggregate loadFromUuid(UUID uuid)
                              throws EventSourcingException

Returns the updated aggregate based on the UUID

Parameters:

uuid - of the Aggregate to recover

Throws:

EventSourcingException - if there is some problem with the handling of the events

getCurrentState

public Aggregate getCurrentState()
                          throws EventSourcingException,
DBQueryException

Restore the aggregate and return the most updated version of the aggregate For doing so, it reconstructs the aggregate from the snapshot and applies the stack of events

Returns:

the updated aggregate

Throws:

EventSourcingException - if there is a problem with the events handlers

DBQueryException - if there is a problem with the DB

apply

public void apply(Event event)
           throws EventSourcingException

Applies an event, given the Event to apply This method will call using reflection the appropriate handler that manage the event

Parameters:

event - to apply

Throws:

EventSourcingException - if there is some problem finding the appropriate handler

createSnapshot

public void createSnapshot()

Generates the snapshot and saves the Aggregate updated information to the repository

rollback

public Aggregate rollback()

Recreates the aggregate based on the last snapshot, deletes all the events vit aggregate version > snapshot version

Returns:

the Aggregate Snapshot