Class DeleteServiceImpl

java.lang.Object

ch.tocco.nice2.persist.entity.impl.delete.DeleteServiceImpl

All Implemented Interfaces:

DeleteService

@Component
public class DeleteServiceImpl
extends Object
implements DeleteService

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	DeleteServiceImpl.EntityDataImpl	Implementation of the DeleteService.EntityData interface, which is part of the result structure.
static class	DeleteServiceImpl.EntityDeletionDataImpl

Nested classes/interfaces inherited from interface DeleteService

DeleteService.DeleteWatcher, DeleteService.EntityData, DeleteService.EntityDeletionData

Field Summary

Fields

Modifier and Type	Field	Description
static final int	DELETE_LIMIT	We can't delete too many entities at once, because the deletion is executed in a single transaction which would consume too much heap space if it contained too many entities.

Constructor Summary

Constructors

Constructor	Description
DeleteServiceImpl(Context context, PersistenceService persistenceService, SecurityManager securityManager, BusinessUnitManager businessUnitManager)

Method Summary

Modifier and Type	Method	Description
Map<EntityId, DeleteService.EntityDeletionData>	createDeletionData(EntityModel model, List<PrimaryKey> keys)	Returns a report that contains information whether the given entities may be deleted using a cascading delete.
List<EntityId>	deleteEntities(EntityModel model, List<PrimaryKey> keys, DeleteService.DeleteWatcher watcher)

Methods inherited from class Object

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

Methods inherited from interface DeleteService

deleteEntities, deleteEntity, getPartitionedTask

Field Details

DELETE_LIMIT

@VisibleForTesting
public static final int DELETE_LIMIT

We can't delete too many entities at once, because the deletion is executed in a single transaction which would consume too much heap space if it contained too many entities. It is difficult to predict how many entities we could delete in a single request, because in this limit isn't represented whatever some listeners might do when triggered and, thus, it isn't the same for all entity models. This limit of 10k is derived by deleting `Membership` entities and measuring memory usage for it -> A total of 10k entities (including related entities, not only Membership entities) already takes up about 300M of the heap space. We shouldn't go higher than that (e.g. a limit of 20k in this constellation already leads to OOM and a crash for a Nice instance with a total memory of 1G).

See Also:

• Constant Field Values

Constructor Details

DeleteServiceImpl

public DeleteServiceImpl(Context context,
 PersistenceService persistenceService,
 SecurityManager securityManager,
 BusinessUnitManager businessUnitManager)

Method Details

createDeletionData

public Map<EntityId, DeleteService.EntityDeletionData> createDeletionData(EntityModel model,
 List<PrimaryKey> keys)

Description copied from interface: DeleteService

Returns a report that contains information whether the given entities may be deleted using a cascading delete. The report also contains all entities that would be additionally deleted and all entities that would block the cascading delete.

Specified by:

createDeletionData in interface DeleteService

Parameters:

model - the entity model

keys - keys of all entities that should be deleted.

deleteEntities

public List<EntityId> deleteEntities(EntityModel model,
 List<PrimaryKey> keys,
 DeleteService.DeleteWatcher watcher)
                              throws DeleteException

Specified by:

deleteEntities in interface DeleteService

Throws:

DeleteException