org.apache.ignite.spi.eventstorage.memory

Class MemoryEventStorageSpi

java.lang.Object

org.apache.ignite.spi.IgniteSpiAdapter

org.apache.ignite.spi.eventstorage.memory.MemoryEventStorageSpi

All Implemented Interfaces:

EventStorageSpi, IgniteSpi

@IgniteSpiMultipleInstancesSupport(value=true)
public class MemoryEventStorageSpi
extends IgniteSpiAdapter
implements EventStorageSpi

In-memory EventStorageSpi implementation. All events are kept in the FIFO queue. If no configuration is provided a default expiration DFLT_EXPIRE_AGE_MS and default count DFLT_EXPIRE_COUNT will be used.

It's recommended not to set huge size and unlimited TTL because this might lead to consuming a lot of memory and result in OutOfMemoryError. Both event expiration time and maximum queue size could be changed at runtime.

Configuration

Mandatory

This SPI has no mandatory configuration parameters.

Optional

The following configuration parameters are optional:

• Event queue size (see setExpireCount(long))
• Event time-to-live value (see setExpireAgeMs(long))
• setFilter(org.apache.ignite.lang.IgnitePredicate) - Event filter that should be used for decision to accept event.

Java Example

MemoryEventStorageSpi is used by default and should be explicitly configured only if some SPI configuration parameters need to be overridden. Examples below insert own events queue size value that differs from default 10000.

 MemoryEventStorageSpi = new MemoryEventStorageSpi();

 // Init own events size.
 spi.setExpireCount(2000);

 IgniteConfiguration cfg = new IgniteConfiguration();

 // Override default event storage SPI.
 cfg.setEventStorageSpi(spi);

 // Starts grid.
 G.start(cfg);
 

Spring Example

MemoryEventStorageSpi can be configured from Spring XML configuration file:

 <bean id="grid.custom.cfg" class="org.apache.ignite.configuration.IgniteConfiguration" singleton="true">
         ...
         <property name="eventStorageSpi">
             <bean class="org.apache.ignite.spi.eventStorage.memory.MemoryEventStorageSpi">
                 <property name="expireCount" value="2000"/>
             </bean>
         </property>
         ...
 </bean>
 

For information about Spring framework visit www.springframework.org

See Also:

EventStorageSpi

Field Summary

Fields

Modifier and Type	Field and Description
static long	DFLT_EXPIRE_AGE_MS Default event time to live value in milliseconds (value is Long.MAX_VALUE).
static int	DFLT_EXPIRE_COUNT Default expire count (value is 10000).

Fields inherited from class org.apache.ignite.spi.IgniteSpiAdapter

ignite, igniteInstanceName

Constructor Summary

Constructors

Constructor and Description
MemoryEventStorageSpi()

Method Summary

Modifier and Type	Method and Description
void	clearAll() Removes all events from the event queue.
long	getExpireAgeMs() See setExpireAgeMs(long)
long	getExpireCount() See setExpireCount(long)
IgnitePredicate<Event>	getFilter() Gets filter for events to be recorded.
long	getQueueSize() Gets current queue size of the event queue.
<T extends Event> Collection<T>	localEvents(IgnitePredicate<T> p) Queries locally-stored events only.
void	record(Event evt) Records single event.
MemoryEventStorageSpi	setExpireAgeMs(long expireAgeMs) Sets events expiration time.
MemoryEventStorageSpi	setExpireCount(long expireCnt) Sets events queue size.
MemoryEventStorageSpi	setFilter(IgnitePredicate<Event> filter) Sets filter for events to be recorded.
MemoryEventStorageSpi	setName(String name) Sets SPI name.
void	spiStart(String igniteInstanceName) This method is called to start SPI.
void	spiStop() This method is called to stop SPI.
String	toString()

Methods inherited from class org.apache.ignite.spi.IgniteSpiAdapter

addTimeoutObject, assertParameter, checkConfigurationConsistency0, clientFailureDetectionTimeout, configInfo, createSpiAttributeName, failureDetectionTimeout, failureDetectionTimeoutEnabled, failureDetectionTimeoutEnabled, getConsistentAttributeNames, getExceptionRegistry, getLocalNode, getName, getNodeAttributes, getSpiContext, ignite, initFailureDetectionTimeout, injectables, injectResources, isNodeStopping, onBeforeStart, onClientDisconnected, onClientReconnected, onContextDestroyed, onContextDestroyed0, onContextInitialized, onContextInitialized0, registerMBean, removeTimeoutObject, started, startInfo, startStopwatch, stopInfo, unregisterMBean

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.ignite.spi.IgniteSpi

getName, getNodeAttributes, onClientDisconnected, onClientReconnected, onContextDestroyed, onContextInitialized

Field Detail

DFLT_EXPIRE_AGE_MS

public static final long DFLT_EXPIRE_AGE_MS

Default event time to live value in milliseconds (value is Long.MAX_VALUE).

See Also:

Constant Field Values

DFLT_EXPIRE_COUNT

public static final int DFLT_EXPIRE_COUNT

Default expire count (value is 10000).

See Also:

Constant Field Values

Constructor Detail

MemoryEventStorageSpi

public MemoryEventStorageSpi()

Method Detail

getFilter

public IgnitePredicate<Event> getFilter()

Gets filter for events to be recorded.

Returns:

Filter to use.

setFilter

@IgniteSpiConfiguration(optional=true)
public MemoryEventStorageSpi setFilter(IgnitePredicate<Event> filter)

Sets filter for events to be recorded.

Parameters:

filter - Filter to use.

Returns:

this for chaining.

spiStart

public void spiStart(String igniteInstanceName)
              throws IgniteSpiException

This method is called to start SPI. After this method returns successfully kernel assumes that SPI is fully operational.

Specified by:

spiStart in interface IgniteSpi

Parameters:

igniteInstanceName - Name of Ignite instance this SPI is being started for (null for default Ignite instance).

Throws:

IgniteSpiException - Throws in case of any error during SPI start.

spiStop

public void spiStop()
             throws IgniteSpiException

This method is called to stop SPI. After this method returns kernel assumes that this SPI is finished and all resources acquired by it are released.

Note that this method can be called at any point including during recovery of failed start. It should make no assumptions on what state SPI will be in when this method is called.

Specified by:

spiStop in interface IgniteSpi

Throws:

IgniteSpiException - Thrown in case of any error during SPI stop.

getExpireAgeMs

public long getExpireAgeMs()

See setExpireAgeMs(long)

Returns:

Event time-to-live.

setExpireAgeMs

@IgniteSpiConfiguration(optional=true)
public MemoryEventStorageSpi setExpireAgeMs(long expireAgeMs)

Sets events expiration time. All events that exceed this value will be removed from the queue when next event comes.

If not provided, default value is DFLT_EXPIRE_AGE_MS.

Parameters:

expireAgeMs - Expiration time in milliseconds.

Returns:

this for chaining.

getExpireCount

public long getExpireCount()

See setExpireCount(long)

Returns:

Maximum event queue size.

setExpireCount

@IgniteSpiConfiguration(optional=true)
public MemoryEventStorageSpi setExpireCount(long expireCnt)

Sets events queue size. Events will be filtered out when new request comes.

If not provided, default value DFLT_EXPIRE_COUNT will be used.

Parameters:

expireCnt - Maximum queue size.

Returns:

this for chaining.

getQueueSize

public long getQueueSize()

Gets current queue size of the event queue.

Returns:

Current queue size of the event queue.

clearAll

public void clearAll()

Removes all events from the event queue.

localEvents

public <T extends Event> Collection<T> localEvents(IgnitePredicate<T> p)

Queries locally-stored events only. Events could be filtered out by given predicate filter.

Specified by:

localEvents in interface EventStorageSpi

Parameters:

p - Event predicate filter.

Returns:

Collection of events.

record

public void record(Event evt)
            throws IgniteSpiException

Records single event.

Specified by:

record in interface EventStorageSpi

Parameters:

evt - Event that should be recorded.

Throws:

IgniteSpiException - If event recording failed for any reason.

setName

public MemoryEventStorageSpi setName(String name)

Sets SPI name.

Overrides:

setName in class IgniteSpiAdapter

Parameters:

name - SPI name.

Returns:

this for chaining.

toString

public String toString()

Overrides:

toString in class Object