org.gridgain.grid.events

Class GridCacheEvent

java.lang.Object

org.gridgain.grid.events.GridEventAdapter

org.gridgain.grid.events.GridCacheEvent

All Implemented Interfaces:

Serializable, Comparable<GridEvent>, GridEvent

public class GridCacheEvent
extends GridEventAdapter

In-memory database (cache) event.

Grid events are used for notification about what happens within the grid. Note that by design GridGain keeps all events generated on the local node locally and it provides APIs for performing a distributed queries across multiple nodes:

• GridEvents.remoteQuery(GridPredicate, long, int...) - asynchronously querying events occurred on the nodes specified, including remote nodes.
• GridEvents.localQuery(GridPredicate, int...) - querying only local events stored on this local node.
• GridEvents.localListen(GridPredicate, int...) - listening to local grid events (events from remote nodes not included).

User can also wait for events using method GridEvents.waitForLocal(GridPredicate, int...).

Events and Performance

Note that by default all events in GridGain are enabled and therefore generated and stored by whatever event storage SPI is configured. GridGain can and often does generate thousands events per seconds under the load and therefore it creates a significant additional load on the system. If these events are not needed by the application this load is unnecessary and leads to significant performance degradation.

It is highly recommended to enable only those events that your application logic requires by using GridConfiguration.getIncludeEventTypes() method in GridGain configuration. Note that certain events are required for GridGain's internal operations and such events will still be generated but not stored by event storage SPI if they are disabled in GridGain configuration.

See Also:

GridEventType.EVT_CACHE_ENTRY_CREATED, GridEventType.EVT_CACHE_ENTRY_DESTROYED, GridEventType.EVT_CACHE_ENTRY_EVICTED, GridEventType.EVT_CACHE_OBJECT_PUT, GridEventType.EVT_CACHE_OBJECT_READ, GridEventType.EVT_CACHE_OBJECT_REMOVED, GridEventType.EVT_CACHE_OBJECT_LOCKED, GridEventType.EVT_CACHE_OBJECT_UNLOCKED, GridEventType.EVT_CACHE_OBJECT_SWAPPED, GridEventType.EVT_CACHE_OBJECT_UNSWAPPED, GridEventType.EVT_CACHE_OBJECT_EXPIRED, Serialized Form

Constructor Summary

Constructors

Constructor and Description
GridCacheEvent(String cacheName, GridNode node, GridNode evtNode, String msg, int type, int part, boolean near, Object key, GridUuid xid, Object lockId, Object newVal, boolean hasNewVal, Object oldVal, boolean hasOldVal, UUID subjId) Constructs cache event.

Method Summary

Methods

Modifier and Type	Method and Description
String	cacheName() Gets cache name.
GridNode	eventNode() Gets node which initiated cache operation or null if that node is not available.
boolean	hasNewValue() Gets flag indicating whether cache entry has new value in case if we only have new value in serialized form in which case newValue() will return null.
boolean	hasOldValue() Gets flag indicating whether cache entry has old value in case if we only have old value in serialized form in which case oldValue() will return null.
boolean	isNear() Gets flag indicating whether event happened on near or partitioned cache.
<K> K	key() Gets cache entry associated with event.
Object	lockId() ID of the lock if held or null if no lock held.
Object	newValue() Gets new value for this event.
Object	oldValue() Gets old value associated with this event.
int	partition() Gets partition for the event which is the partition the key belongs to.
String	shortDisplay() Gets a shortened version of toString() result.
UUID	subjectId() Gets security subject ID initiated this cache event, if available.
String	toString()
GridUuid	xid() ID of surrounding cache cache transaction or null if there is no surrounding transaction.

Methods inherited from class org.gridgain.grid.events.GridEventAdapter

compareTo, equals, hashCode, id, localOrder, message, message, name, node, node, timestamp, type, type

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

GridCacheEvent

public GridCacheEvent(String cacheName,
              GridNode node,
              @Nullable
              GridNode evtNode,
              String msg,
              int type,
              int part,
              boolean near,
              Object key,
              GridUuid xid,
              Object lockId,
              Object newVal,
              boolean hasNewVal,
              Object oldVal,
              boolean hasOldVal,
              UUID subjId)

Constructs cache event.

Parameters:

cacheName - Cache name.

node - Local node.

evtNode - Event node ID.

msg - Event message.

type - Event type.

part - Partition for the event (usually the partition the key belongs to).

near - Flag indicating whether event happened on near or partitioned cache.

key - Cache key.

xid - Transaction ID.

lockId - Lock ID.

newVal - New value.

hasNewVal - Flag indicating whether new value is present in case if we don't have it in deserialized form.

oldVal - Old value.

hasOldVal - Flag indicating whether old value is present in case if we don't have it in deserialized form.

Method Detail

cacheName

@Nullable
public String cacheName()

Gets cache name.

Returns:

Cache name.

partition

public int partition()

Gets partition for the event which is the partition the key belongs to.

Returns:

Partition for the event.

isNear

public boolean isNear()

Gets flag indicating whether event happened on near or partitioned cache.

Returns:

Flag indicating whether event happened on near or partitioned cache.

eventNode

@Nullable
public GridNode eventNode()

Gets node which initiated cache operation or null if that node is not available.

Returns:

Node which initiated cache operation or null if that node is not available.

key

@Nullable
public <K> K key()

Gets cache entry associated with event.

Returns:

Cache entry associated with event.

xid

@Nullable
public GridUuid xid()

ID of surrounding cache cache transaction or null if there is no surrounding transaction.

Returns:

ID of surrounding cache transaction.

lockId

@Nullable
public Object lockId()

ID of the lock if held or null if no lock held.

Returns:

ID of the lock if held.

newValue

@Nullable
public Object newValue()

Gets new value for this event.

Returns:

New value associated with event (null if event is GridEventType.EVT_CACHE_OBJECT_REMOVED.

oldValue

@Nullable
public Object oldValue()

Gets old value associated with this event.

Returns:

Old value associated with event.

hasOldValue

public boolean hasOldValue()

Gets flag indicating whether cache entry has old value in case if we only have old value in serialized form in which case oldValue() will return null.

Returns:

Flag indicating whether there is old value associated with this event.

hasNewValue

public boolean hasNewValue()

Gets flag indicating whether cache entry has new value in case if we only have new value in serialized form in which case newValue() will return null.

Returns:

Flag indicating whether there is new value associated with this event.

subjectId

@Nullable
public UUID subjectId()

Gets security subject ID initiated this cache event, if available. This property is available only for GridEventType.EVT_CACHE_OBJECT_PUT, GridEventType.EVT_CACHE_OBJECT_REMOVED and GridEventType.EVT_CACHE_OBJECT_READ cache events.

Subject ID will be set either to nodeId initiated cache update or read or client ID initiated cache update or read.

Returns:

Subject ID.

shortDisplay

public String shortDisplay()

Gets a shortened version of toString() result. Suitable for humans to read.

Specified by:

shortDisplay in interface GridEvent

Overrides:

shortDisplay in class GridEventAdapter

Returns:

Shortened version of toString() result.

toString

public String toString()

Overrides:

toString in class GridEventAdapter