org.jgroups.blocks

Class ReplCache<K,V>

java.lang.Object

org.jgroups.blocks.ReplCache<K,V>

All Implemented Interfaces:

Cache.ChangeListener, MembershipListener

public class ReplCache<K,V>
extends java.lang.Object
implements MembershipListener, Cache.ChangeListener

Cache which allows for replication factors per data items; the factor determines how many replicas of a key/value we create across the cluster.
See doc/design/ReplCache.txt for details.

Author:

Bela Ban

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	ReplCache.ChangeListener
static class	ReplCache.ConsistentHashFunction<K>
static interface	ReplCache.HashFunction<K>
static interface	ReplCache.HashFunctionFactory<K>
static class	ReplCache.Value<V>

Field Summary

Fields

Modifier and Type	Field and Description
protected static java.util.Map<java.lang.Short,java.lang.reflect.Method>	methods

Constructor Summary

Constructors

Constructor and Description
ReplCache(java.lang.String props, java.lang.String cluster_name)

Method Summary

Modifier and Type	Method and Description
Cache.Value<ReplCache.Value<V>>	_get(K key)
V	_put(K key, V val, short repl_count, long timeout)
V	_put(K key, V val, short repl_count, long timeout, boolean force)
V	_remove(K key)
void	_removeMany(java.util.Set<K> keys)
void	addChangeListener(ReplCache.ChangeListener l)
void	addMembershipListener(MembershipListener l)
void	block() Called (usually by the FLUSH protocol), as an indication that the member should stop sending messages.
void	changed()
void	clear() Removes all keys and values in the L2 and L1 caches
java.lang.String	dump()
V	get(K key) Returns the value associated with key
long	getCachingTime()
long	getCallTimeout()
java.lang.String	getClusterName()
int	getClusterSize()
short	getDefaultReplicationCount()
ReplCache.HashFunction	getHashFunction()
ReplCache.HashFunctionFactory	getHashFunctionFactory()
Cache<K,V>	getL1Cache()
Cache<K,ReplCache.Value<V>>	getL2Cache()
Address	getLocalAddress()
java.lang.String	getLocalAddressAsString()
java.lang.String	getProps()
java.lang.String	getView()
boolean	isL1CacheEnabled()
boolean	isMigrateData()
void	mcastEntries()
void	put(K key, V val)
void	put(K key, V val, short repl_count, long timeout) Places a key/value pair into one or several nodes in the cluster.
void	put(K key, V val, short repl_count, long timeout, boolean synchronous) Places a key/value pair into one or several nodes in the cluster.
void	remove(K key) Removes key in all nodes in the cluster, both from their local hashmaps and L1 caches
void	remove(K key, boolean synchronous) Removes key in all nodes in the cluster, both from their local hashmaps and L1 caches
void	removeChangeListener(ReplCache.ChangeListener l)
void	removeMembershipListener(MembershipListener l)
void	setCachingTime(long caching_time)
void	setCallTimeout(long call_timeout)
void	setClusterName(java.lang.String cluster_name)
void	setDefaultReplicationCount(short default_replication_count)
void	setHashFunction(ReplCache.HashFunction<K> hash_function)
void	setHashFunctionFactory(ReplCache.HashFunctionFactory<K> hash_function_factory)
void	setL1Cache(Cache<K,V> cache)
void	setL2Cache(Cache<K,ReplCache.Value<V>> cache)
void	setMigrateData(boolean migrate_data)
void	setProps(java.lang.String props)
void	start()
void	stop()
void	suspect(Address suspected_mbr) Called whenever a member is suspected of having crashed, but has not yet been excluded.
java.lang.String	toString()
void	unblock() Called after the FLUSH protocol has unblocked previously blocked senders, and messages can be sent again.
void	viewAccepted(View new_view) Called when a change in membership has occurred.

Methods inherited from class java.lang.Object

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

Field Detail

methods

protected static final java.util.Map<java.lang.Short,java.lang.reflect.Method> methods

Constructor Detail

ReplCache

public ReplCache(java.lang.String props,
                 java.lang.String cluster_name)

Method Detail

getProps

public java.lang.String getProps()

setProps

public void setProps(java.lang.String props)

getLocalAddress

public Address getLocalAddress()

getLocalAddressAsString

public java.lang.String getLocalAddressAsString()

getView

public java.lang.String getView()

getClusterSize

public int getClusterSize()

isL1CacheEnabled

public boolean isL1CacheEnabled()

getClusterName

public java.lang.String getClusterName()

setClusterName

public void setClusterName(java.lang.String cluster_name)

getCallTimeout

public long getCallTimeout()

setCallTimeout

public void setCallTimeout(long call_timeout)

getCachingTime

public long getCachingTime()

setCachingTime

public void setCachingTime(long caching_time)

isMigrateData

public boolean isMigrateData()

setMigrateData

public void setMigrateData(boolean migrate_data)

getDefaultReplicationCount

public short getDefaultReplicationCount()

setDefaultReplicationCount

public void setDefaultReplicationCount(short default_replication_count)

getHashFunction

public ReplCache.HashFunction getHashFunction()

setHashFunction

public void setHashFunction(ReplCache.HashFunction<K> hash_function)

getHashFunctionFactory

public ReplCache.HashFunctionFactory getHashFunctionFactory()

setHashFunctionFactory

public void setHashFunctionFactory(ReplCache.HashFunctionFactory<K> hash_function_factory)

addMembershipListener

public void addMembershipListener(MembershipListener l)

removeMembershipListener

public void removeMembershipListener(MembershipListener l)

addChangeListener

public void addChangeListener(ReplCache.ChangeListener l)

removeChangeListener

public void removeChangeListener(ReplCache.ChangeListener l)

getL1Cache

public Cache<K,V> getL1Cache()

setL1Cache

public void setL1Cache(Cache<K,V> cache)

getL2Cache

public Cache<K,ReplCache.Value<V>> getL2Cache()

setL2Cache

public void setL2Cache(Cache<K,ReplCache.Value<V>> cache)

start

public void start()
           throws java.lang.Exception

Throws:

java.lang.Exception

stop

public void stop()

put

public void put(K key,
                V val,
                short repl_count,
                long timeout,
                boolean synchronous)

Places a key/value pair into one or several nodes in the cluster.

Parameters:

key - The key, needs to be serializable

val - The value, needs to be serializable

repl_count - Number of replicas. The total number of times a data item should be present in a cluster. Needs to be > 0

• -1: create key/val in all the nodes in the cluster
• 1: create key/val only in one node in the cluster, picked by computing the consistent hash of KEY
• K > 1: create key/val in those nodes in the cluster which match the consistent hashes created for KEY

timeout - Expiration time for key/value.

• -1: don't cache at all in the L1 cache
• 0: cache forever, until removed or evicted because we need space for newer elements
• > 0: number of milliseconds to keep an idle element in the cache. An element is idle when not accessed.

synchronous - Whether or not to block until all cluster nodes have applied the change

put

public void put(K key,
                V val,
                short repl_count,
                long timeout)

Places a key/value pair into one or several nodes in the cluster.

Parameters:

key - The key, needs to be serializable

val - The value, needs to be serializable

repl_count - Number of replicas. The total number of times a data item should be present in a cluster. Needs to be > 0

• -1: create key/val in all the nodes in the cluster
• 1: create key/val only in one node in the cluster, picked by computing the consistent hash of KEY
• K > 1: create key/val in those nodes in the cluster which match the consistent hashes created for KEY

timeout - Expiration time for key/value.

• -1: don't cache at all in the L1 cache
• 0: cache forever, until removed or evicted because we need space for newer elements
• > 0: number of milliseconds to keep an idle element in the cache. An element is idle when not accessed.

put

public void put(K key,
                V val)

get

public V get(K key)

Returns the value associated with key

Parameters:

key - The key, has to be serializable

Returns:

The value associated with key, or null

remove

public void remove(K key)

Removes key in all nodes in the cluster, both from their local hashmaps and L1 caches

Parameters:

key - The key, needs to be serializable

remove

public void remove(K key,
                   boolean synchronous)

Removes key in all nodes in the cluster, both from their local hashmaps and L1 caches

Parameters:

key - The key, needs to be serializable

clear

public void clear()

Removes all keys and values in the L2 and L1 caches

_put

public V _put(K key,
              V val,
              short repl_count,
              long timeout)

_put

public V _put(K key,
              V val,
              short repl_count,
              long timeout,
              boolean force)

Parameters:

key -

val -

repl_count -

timeout -

force - Skips acceptance checking and simply adds the key/value

Returns:

_get

public Cache.Value<ReplCache.Value<V>> _get(K key)

_remove

public V _remove(K key)

_removeMany

public void _removeMany(java.util.Set<K> keys)

viewAccepted

public void viewAccepted(View new_view)

Description copied from interface: MembershipListener

Called when a change in membership has occurred. No long running actions, sending of messages or anything that could block should be done in this callback. If some long running action needs to be performed, it should be done in a separate thread.

Note that on reception of the first view (a new member just joined), the channel will not yet be in the connected state. This only happens when Channel.connect(String) returns.

Specified by:

viewAccepted in interface MembershipListener

suspect

public void suspect(Address suspected_mbr)

Description copied from interface: MembershipListener

Called whenever a member is suspected of having crashed, but has not yet been excluded.

Specified by:

suspect in interface MembershipListener

block

public void block()

Description copied from interface: MembershipListener

Called (usually by the FLUSH protocol), as an indication that the member should stop sending messages. Any messages sent after returning from this callback might get blocked by the FLUSH protocol. When the FLUSH protocol is done, and messages can be sent again, the FLUSH protocol will simply unblock all pending messages. If a callback for unblocking is desired, implement MembershipListener.unblock(). Note that block() is the equivalent of reception of a BlockEvent in the pull mode.

Specified by:

block in interface MembershipListener

unblock

public void unblock()

Description copied from interface: MembershipListener

Called after the FLUSH protocol has unblocked previously blocked senders, and messages can be sent again. This callback only needs to be implemented if we require a notification of that.

Note that during new view installation we provide guarantee that unblock invocation strictly follows view installation at some node A belonging to that view . However, some other message M may squeeze in between view and unblock callbacks. For more details see https://jira.jboss.org/jira/browse/JGRP-986

Specified by:

unblock in interface MembershipListener

changed

public void changed()

Specified by:

changed in interface Cache.ChangeListener

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

dump

public java.lang.String dump()

mcastEntries

public void mcastEntries()