com.hazelcast.map.impl.journal

Interface MapEventJournal

All Superinterfaces:

EventJournal<InternalEventJournalMapEvent>

All Known Implementing Classes:

RingbufferMapEventJournalImpl

public interface MapEventJournal
extends EventJournal<InternalEventJournalMapEvent>

The event journal is a container for events related to a data structure. This interface provides methods for map event journals. This includes events such as add, update, remove, evict and others. Each map and partition has it's own event journal.

If a map is destroyed or the migrated, the related event journal will be destroyed or migrated as well. In this sense, the event journal is co-located with the map partition and it's replicas.

NOTE : Map evictions are based on random samples which are then compared according to an eviction policy. This is done separately on the partition owner and the backup replica and can cause different entries to be evicted on the primary and backup replica. Because of this, the record store can contain different entries and the event journal can contain eviction/remove events for different entries on different replicas. This may cause some issues if the partition owner crashes and the backup replica is promoted to the partition owner. Readers of the event journal will then continue reading from the promoted replica and may get update and remove events for entries which have already been removed.

Since:

3.9

Method Summary

Modifier and Type	Method and Description
boolean	hasEventJournal(ObjectNamespace namespace) Returns true if the object has a configured and enabled event journal.
void	writeAddEvent(EventJournalConfig journalConfig, ObjectNamespace namespace, int partitionId, Data key, Object value) Writes an EntryEventType.ADDED to the event journal.
void	writeEvictEvent(EventJournalConfig journalConfig, ObjectNamespace namespace, int partitionId, Data key, Object value) Writes an EntryEventType.EVICTED to the event journal.
void	writeRemoveEvent(EventJournalConfig journalConfig, ObjectNamespace namespace, int partitionId, Data key, Object value) Writes an EntryEventType.REMOVED to the event journal.
void	writeUpdateEvent(EventJournalConfig journalConfig, ObjectNamespace namespace, int partitionId, Data key, Object oldValue, Object newValue) Writes an EntryEventType.UPDATED to the event journal.

Methods inherited from interface com.hazelcast.journal.EventJournal

cleanup, destroy, getEventJournalConfig, getWaitNotifyKey, isAvailableOrNextSequence, isNextAvailableSequence, newestSequence, oldestSequence, readMany, toRingbufferConfig

Method Detail

writeUpdateEvent

void writeUpdateEvent(EventJournalConfig journalConfig,
                      ObjectNamespace namespace,
                      int partitionId,
                      Data key,
                      Object oldValue,
                      Object newValue)

Writes an EntryEventType.UPDATED to the event journal. If there is no event journal configured for this map, the method will do nothing. If an event is added to the event journal, all parked operations waiting for new events on that journal will be unparked.

Parameters:

journalConfig - the event journal config for the map in which the event occurred

namespace - the map namespace

partitionId - the entry key partition

key - the entry key

oldValue - the old value

newValue - the new value

writeAddEvent

void writeAddEvent(EventJournalConfig journalConfig,
                   ObjectNamespace namespace,
                   int partitionId,
                   Data key,
                   Object value)

Writes an EntryEventType.ADDED to the event journal. If there is no event journal configured for this map, the method will do nothing. If an event is added to the event journal, all parked operations waiting for new events on that journal will be unparked.

Parameters:

journalConfig - the event journal config for the map in which the event occurred

namespace - the map namespace

partitionId - the entry key partition

key - the entry key

value - the entry value

writeRemoveEvent

void writeRemoveEvent(EventJournalConfig journalConfig,
                      ObjectNamespace namespace,
                      int partitionId,
                      Data key,
                      Object value)

Writes an EntryEventType.REMOVED to the event journal. If there is no event journal configured for this map, the method will do nothing. If an event is added to the event journal, all parked operations waiting for new events on that journal will be unparked.

Parameters:

journalConfig - the event journal config for the map in which the event occurred

namespace - the map namespace

partitionId - the entry key partition

key - the entry key

value - the entry value

writeEvictEvent

void writeEvictEvent(EventJournalConfig journalConfig,
                     ObjectNamespace namespace,
                     int partitionId,
                     Data key,
                     Object value)

Writes an EntryEventType.EVICTED to the event journal. If there is no event journal configured for this map, the method will do nothing. If an event is added to the event journal, all parked operations waiting for new events on that journal will be unparked.

Parameters:

journalConfig - the event journal config for the map in which the event occurred

namespace - the map namespace

partitionId - the entry key partition

key - the entry key

value - the entry value

hasEventJournal

boolean hasEventJournal(ObjectNamespace namespace)

Returns true if the object has a configured and enabled event journal.

Specified by:

hasEventJournal in interface EventJournal<InternalEventJournalMapEvent>

Parameters:

namespace - the object namespace

Returns:

true if the object has a configured and enabled event journal, false otherwise