com.opensymphony.oscache.plugins.clustersupport
Class JavaGroupsBroadcastingListener

java.lang.Object
  com.opensymphony.oscache.plugins.clustersupport.AbstractBroadcastingListener
      com.opensymphony.oscache.plugins.clustersupport.JavaGroupsBroadcastingListener

All Implemented Interfaces:

CacheEntryEventListener, CacheEventListener, LifecycleAware, EventListener, org.jgroups.blocks.NotificationBus.Consumer

public class JavaGroupsBroadcastingListener
extends AbstractBroadcastingListener
implements org.jgroups.blocks.NotificationBus.Consumer

A concrete implementation of the AbstractBroadcastingListener based on the JavaGroups library. This Class uses JavaGroups to broadcast cache flush messages across a cluster.

One of the following properties should be configured in oscache.properties for this listener:

• cache.cluster.multicast.ip - The multicast IP that JavaGroups should use for broadcasting
• cache.cluster.properties - The JavaGroups channel properties to use. Allows for precise control over the behaviour of JavaGroups

Please refer to the clustering documentation for further details on the configuration of this listener.

Author:

Chris Miller

Field Summary

private org.jgroups.blocks.NotificationBus	bus
private static String	BUS_NAME
private static String	CHANNEL_PROPERTIES
private static String	DEFAULT_CHANNEL_PROPERTIES_POST The second half of the default channel properties.
private static String	DEFAULT_CHANNEL_PROPERTIES_PRE The first half of the default channel properties.
private static String	DEFAULT_MULTICAST_IP
private static Log	log
private static String	MULTICAST_IP_PROPERTY

Fields inherited from class com.opensymphony.oscache.plugins.clustersupport.AbstractBroadcastingListener

cache, CLUSTER_ORIGIN

Constructor Summary

JavaGroupsBroadcastingListener()

Method Summary

void	finialize() Shuts down the JavaGroups being managed by this listener.
Serializable	getCache() We are not using the caching, so we just return something that identifies us.
void	handleNotification(Serializable serializable) Handles incoming notification messages from JavaGroups.
void	initialize(Cache cache, Config config) Initializes the broadcasting listener by starting up a JavaGroups notification bus instance to handle incoming and outgoing messages.
void	memberJoined(org.jgroups.Address address) A callback that is fired when a new member joins the cluster.
void	memberLeft(org.jgroups.Address address) A callback that is fired when an existing member leaves the cluster.
protected void	sendNotification(ClusterNotification message) Uses JavaGroups to broadcast the supplied notification message across the cluster.

Methods inherited from class com.opensymphony.oscache.plugins.clustersupport.AbstractBroadcastingListener

cacheEntryAdded, cacheEntryFlushed, cacheEntryRemoved, cacheEntryUpdated, cacheFlushed, cacheGroupAdded, cacheGroupEntryAdded, cacheGroupEntryRemoved, cacheGroupFlushed, cacheGroupRemoved, cacheGroupUpdated, cachePatternFlushed, handleClusterNotification

Methods inherited from class java.lang.Object

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

Field Detail

log

private static final Log log

BUS_NAME

private static final String BUS_NAME

See Also:

Constant Field Values

CHANNEL_PROPERTIES

private static final String CHANNEL_PROPERTIES

See Also:

Constant Field Values

MULTICAST_IP_PROPERTY

private static final String MULTICAST_IP_PROPERTY

See Also:

Constant Field Values

DEFAULT_CHANNEL_PROPERTIES_PRE

private static final String DEFAULT_CHANNEL_PROPERTIES_PRE

The first half of the default channel properties. They default channel properties are:

 UDP(mcast_addr=*.*.*.*;mcast_port=45566;ip_ttl=32;\
 mcast_send_buf_size=150000;mcast_recv_buf_size=80000):\
 PING(timeout=2000;num_initial_members=3):\
 MERGE2(min_interval=5000;max_interval=10000):\
 FD_SOCK:VERIFY_SUSPECT(timeout=1500):\
 pbcast.NAKACK(gc_lag=50;retransmit_timeout=300,600,1200,2400,4800;max_xmit_size=8192):\
 UNICAST(timeout=300,600,1200,2400):\
 pbcast.STABLE(desired_avg_gossip=20000):\
 FRAG(frag_size=8096;down_thread=false;up_thread=false):\
 pbcast.GMS(join_timeout=5000;join_retry_timeout=2000;shun=false;print_local_addr=true)
 

Where *.*.*.* is the specified multicast IP, which defaults to 231.12.21.132.

See Also:

Constant Field Values

DEFAULT_CHANNEL_PROPERTIES_POST

private static final String DEFAULT_CHANNEL_PROPERTIES_POST

The second half of the default channel properties. They default channel properties are:

 UDP(mcast_addr=*.*.*.*;mcast_port=45566;ip_ttl=32;\
 mcast_send_buf_size=150000;mcast_recv_buf_size=80000):\
 PING(timeout=2000;num_initial_members=3):\
 MERGE2(min_interval=5000;max_interval=10000):\
 FD_SOCK:VERIFY_SUSPECT(timeout=1500):\
 pbcast.NAKACK(gc_lag=50;retransmit_timeout=300,600,1200,2400,4800;max_xmit_size=8192):\
 UNICAST(timeout=300,600,1200,2400):\
 pbcast.STABLE(desired_avg_gossip=20000):\
 FRAG(frag_size=8096;down_thread=false;up_thread=false):\
 pbcast.GMS(join_timeout=5000;join_retry_timeout=2000;shun=false;print_local_addr=true)
 

Where *.*.*.* is the specified multicast IP, which defaults to 231.12.21.132.

See Also:

Constant Field Values

DEFAULT_MULTICAST_IP

private static final String DEFAULT_MULTICAST_IP

See Also:

Constant Field Values

bus

private org.jgroups.blocks.NotificationBus bus

Constructor Detail

JavaGroupsBroadcastingListener

public JavaGroupsBroadcastingListener()

Method Detail

initialize

public void initialize(Cache cache,
                       Config config)
                throws InitializationException

Initializes the broadcasting listener by starting up a JavaGroups notification bus instance to handle incoming and outgoing messages.

Specified by:

initialize in interface LifecycleAware

Overrides:

initialize in class AbstractBroadcastingListener

Parameters:

config - An OSCache configuration object.

cache - the cache instance that this listener is attached to.

Throws:

InitializationException - If this listener has already been initialized.

finialize

public void finialize()
               throws FinalizationException

Shuts down the JavaGroups being managed by this listener. This occurs once the cache is shut down and this listener is no longer in use.

Specified by:

finialize in interface LifecycleAware

Throws:

FinalizationException

sendNotification

protected void sendNotification(ClusterNotification message)

Uses JavaGroups to broadcast the supplied notification message across the cluster.

Specified by:

sendNotification in class AbstractBroadcastingListener

Parameters:

message - The cluster nofication message to broadcast.

handleNotification

public void handleNotification(Serializable serializable)

Handles incoming notification messages from JavaGroups. This method should never be called directly.

Specified by:

handleNotification in interface org.jgroups.blocks.NotificationBus.Consumer

Parameters:

serializable - The incoming message object. This must be a ClusterNotification.

getCache

public Serializable getCache()

We are not using the caching, so we just return something that identifies us. This method should never be called directly.

Specified by:

getCache in interface org.jgroups.blocks.NotificationBus.Consumer

memberJoined

public void memberJoined(org.jgroups.Address address)

A callback that is fired when a new member joins the cluster. This method should never be called directly.

Specified by:

memberJoined in interface org.jgroups.blocks.NotificationBus.Consumer

Parameters:

address - The address of the member who just joined.

memberLeft

public void memberLeft(org.jgroups.Address address)

A callback that is fired when an existing member leaves the cluster. This method should never be called directly.

Specified by:

memberLeft in interface org.jgroups.blocks.NotificationBus.Consumer

Parameters:

address - The address of the member who left.