net.sf.ehcache.distribution.jgroups
Class JGroupManager

java.lang.Object
  net.sf.ehcache.distribution.jgroups.JGroupManager

All Implemented Interfaces:

java.rmi.Remote, CacheManagerPeerProvider, CachePeer, org.jgroups.blocks.NotificationBus.Consumer

public class JGroupManager
extends java.lang.Object
implements org.jgroups.blocks.NotificationBus.Consumer, CachePeer, CacheManagerPeerProvider

The main Jgroup class for replication via JGroup. Starts up the Jgroup communication bus and listen for message in the bus. Because of Ehcache design we have to register this as a CachePeer. In reality this class listen for change on the bus and tells the cachemanager to update.

Version:

$Id: JGroupManager.java 704 2008-07-13 00:17:52Z gregluck $

Author:

Pierre Monestie (pmonestie__REMOVE__THIS__@gmail.com), Greg Luck

Constructor Summary

JGroupManager(CacheManager m, java.lang.String connect)
Construc a new JGroupManager with a specific Jgroups connection String

Method Summary

void	dispose() Providers may be doing all sorts of exotic things and need to be able to clean up on dispose.
java.io.Serializable	getCache()
java.util.List	getElements(java.util.List keys) Gets a list of elements from the cache, for a list of keys, without updating Element statistics.
java.lang.String	getGuid() Gets the globally unique id for the underlying Cache instance.
java.util.List	getKeys() Returns a list of all elements in the cache, whether or not they are expired.
java.lang.String	getName() Gets the cache name.
Element	getQuiet(java.io.Serializable key) Gets an element from the cache, without updating Element statistics.
Status	getStatus()
long	getTimeForClusterToForm() Time for a cluster to form.
java.lang.String	getUrl() The URL for the remote replicator to connect.
java.lang.String	getUrlBase() The URL base for the remote replicator to connect.
void	handleNotification(java.io.Serializable arg0) Handles notification: Looks at type of message and unwrap if the argument is a list
void	init() Notifies providers to initialise themselves.
java.util.List	listRemoteCachePeers(Ehcache cache)
void	memberJoined(org.jgroups.Address arg0)
void	memberLeft(org.jgroups.Address arg0)
void	put(Element element) Put an element in the cache.
void	registerPeer(java.lang.String rmiUrl) Register a new peer.
boolean	remove(java.io.Serializable key) Removes an Element from the Cache.
void	removeAll() Removes all cached items.
void	send(java.util.List eventMessages) Send the cache peer with an ordered list of EventMessages.
void	unregisterPeer(java.lang.String rmiUrl) Unregisters a peer.

Methods inherited from class java.lang.Object

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

Constructor Detail

JGroupManager

public JGroupManager(CacheManager m,
                     java.lang.String connect)

Construc a new JGroupManager with a specific Jgroups connection String

Parameters:

m - the cache manager

connect - the connection String

Method Detail

getCache

public java.io.Serializable getCache()

Specified by:

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

handleNotification

public void handleNotification(java.io.Serializable arg0)

Handles notification: Looks at type of message and unwrap if the argument is a list

Specified by:

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

memberJoined

public void memberJoined(org.jgroups.Address arg0)

Specified by:

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

memberLeft

public void memberLeft(org.jgroups.Address arg0)

Specified by:

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

getElements

public java.util.List getElements(java.util.List keys)
                           throws java.rmi.RemoteException

Gets a list of elements from the cache, for a list of keys, without updating Element statistics. Time to idle lifetimes are therefore not affected.

Cache statistics are still updated.

Specified by:

getElements in interface CachePeer

Parameters:

keys - a list of serializable values which represent keys

Returns:

a list of Elements. If an element was not found or null, it will not be in the list.

Throws:

java.rmi.RemoteException

getGuid

public java.lang.String getGuid()
                         throws java.rmi.RemoteException

Gets the globally unique id for the underlying Cache instance.

Specified by:

getGuid in interface CachePeer

Returns:

a String representation of the GUID

Throws:

java.rmi.RemoteException

getKeys

public java.util.List getKeys()
                       throws java.rmi.RemoteException

Returns a list of all elements in the cache, whether or not they are expired.

The returned keys are unique and can be considered a set.

The List returned is not live. It is a copy.

The time taken is O(n). On a single cpu 1.8Ghz P4, approximately 8ms is required for each 1000 entries.

Specified by:

getKeys in interface CachePeer

Returns:

a list of Object keys

Throws:

java.rmi.RemoteException

getName

public java.lang.String getName()
                         throws java.rmi.RemoteException

Gets the cache name.

Specified by:

getName in interface CachePeer

Throws:

java.rmi.RemoteException

getQuiet

public Element getQuiet(java.io.Serializable key)
                 throws java.rmi.RemoteException

Gets an element from the cache, without updating Element statistics. Cache statistics are still updated.

Specified by:

getQuiet in interface CachePeer

Parameters:

key - a serializable value

Returns:

the element, or null, if it does not exist.

Throws:

java.rmi.RemoteException

getUrl

public java.lang.String getUrl()
                        throws java.rmi.RemoteException

The URL for the remote replicator to connect. The value will only have meaning for a specific implementation of replicator and remote peer.

This method is not meant to be used remotely. The replicator already needs to know this. It has to throw RemoteException to comply with RMI requirements

Specified by:

getUrl in interface CachePeer

Returns:

the URL as a string

Throws:

java.rmi.RemoteException

getUrlBase

public java.lang.String getUrlBase()
                            throws java.rmi.RemoteException

The URL base for the remote replicator to connect. The value will have meaning only to a specific implementation of replicator and remote peer.

Specified by:

getUrlBase in interface CachePeer

Throws:

java.rmi.RemoteException

put

public void put(Element element)
         throws java.lang.IllegalArgumentException,
                java.lang.IllegalStateException,
                java.rmi.RemoteException

Put an element in the cache.

Resets the access statistics on the element, which would be the case if it has previously been gotten from a cache, and is now being put back.

Specified by:

put in interface CachePeer

Throws:

java.lang.IllegalArgumentException - if the element is null

java.lang.IllegalStateException - if the cache is not Status.STATUS_ALIVE

java.rmi.RemoteException

remove

public boolean remove(java.io.Serializable key)
               throws java.lang.IllegalStateException,
                      java.rmi.RemoteException

Removes an Element from the Cache. This also removes it from any stores it may be in.

Specified by:

remove in interface CachePeer

Returns:

true if the element was removed, false if it was not found in the cache

Throws:

java.lang.IllegalStateException - if the cache is not Status.STATUS_ALIVE

java.rmi.RemoteException

removeAll

public void removeAll()
               throws java.rmi.RemoteException,
                      java.lang.IllegalStateException

Removes all cached items.

Specified by:

removeAll in interface CachePeer

Throws:

java.lang.IllegalStateException - if the cache is not Status.STATUS_ALIVE

java.rmi.RemoteException

send

public void send(java.util.List eventMessages)
          throws java.rmi.RemoteException

Send the cache peer with an ordered list of EventMessages.

This enables multiple messages to be delivered in one network invocation.

Specified by:

send in interface CachePeer

Parameters:

eventMessages - a list of type EventMessage

Throws:

java.rmi.RemoteException

getStatus

public Status getStatus()

Returns:

the Status of the manager

dispose

public void dispose()
             throws CacheException

Providers may be doing all sorts of exotic things and need to be able to clean up on dispose.

Specified by:

dispose in interface CacheManagerPeerProvider

Throws:

CacheException

getTimeForClusterToForm

public long getTimeForClusterToForm()

Time for a cluster to form. This varies considerably, depending on the implementation.

Specified by:

getTimeForClusterToForm in interface CacheManagerPeerProvider

Returns:

the time in ms, for a cluster to form

init

public void init()

Notifies providers to initialise themselves.

Specified by:

init in interface CacheManagerPeerProvider

listRemoteCachePeers

public java.util.List listRemoteCachePeers(Ehcache cache)
                                    throws CacheException

Specified by:

listRemoteCachePeers in interface CacheManagerPeerProvider

Returns:

a list of CachePeer peers for the given cache, excluding the local peer.

Throws:

CacheException

registerPeer

public void registerPeer(java.lang.String rmiUrl)

Register a new peer.

Specified by:

registerPeer in interface CacheManagerPeerProvider

unregisterPeer

public void unregisterPeer(java.lang.String rmiUrl)

Unregisters a peer.

Specified by:

unregisterPeer in interface CacheManagerPeerProvider