org.apache.catalina.tribes.tipis

Class AbstractReplicatedMap

public abstract class AbstractReplicatedMap extends ConcurrentHashMap implements RpcCallback, ChannelListener, MembershipListener, Heartbeat

Version: 1.0

Author: Filip Hanik

Nested Class Summary
static class	AbstractReplicatedMap.MapEntry
static class	AbstractReplicatedMap.MapMessage
static interface	AbstractReplicatedMap.MapOwner

Field Summary
protected long	accessTimeout Since the map keeps internal membership this is the timeout for a ping message to be responded to If a remote map doesn't respond within this timeframe, its considered dead.
protected Channel	channel Reference to the channel for sending messages
protected int	channelSendOptions Our default send options
protected int	currentNode The node we are currently backing up data to, this index will rotate on a round robin basis
static int	DEFAULT_INITIAL_CAPACITY The default initial capacity - MUST be a power of two.
static float	DEFAULT_LOAD_FACTOR The load factor used when none specified in constructor.
protected ClassLoader[]	externalLoaders External class loaders if serialization and deserialization is to be performed successfully.
protected static Log	log
protected byte[]	mapContextName The Map context name makes this map unique, this allows us to have more than one map shared through one channel
protected HashMap	mapMembers A list of members in our map
protected String	mapname Readable string of the mapContextName value
protected AbstractReplicatedMap.MapOwner	mapOwner The owner of this map, ala a SessionManager for example
protected RpcChannel	rpcChannel The RpcChannel to send RPC messages through
protected long	rpcTimeout Timeout for RPC messages, how long we will wait for a reply
protected Object	stateMutex Simple lock object for transfers
protected boolean	stateTransferred Has the state been transferred

Constructor Summary
	AbstractReplicatedMap(AbstractReplicatedMap.MapOwner owner, Channel channel, long timeout, String mapContextName, int initialCapacity, float loadFactor, int channelSendOptions, ClassLoader[] cls) Creates a new map

Method Summary
boolean	accept(Serializable msg, Member sender)
void	breakdown()
protected void	broadcast(int msgtype, boolean rpc) Helper method to broadcast a message to all members in a channel
void	clear()
void	clear(boolean notify)
Object	clone()
boolean	containsKey(Object key) Returns true if the key has an entry in the map.
boolean	containsValue(Object value)
Set	entrySet()
Set	entrySetFull() Returns the entire contents of the map Map.Entry.getValue() will return a LazyReplicatedMap.MapEntry object containing all the information about the object.
boolean	equals(Object o)
Member[]	excludeFromSet(Member[] mbrs, Member[] set)
void	finalize()
Object	get(Object key)
long	getAccessTimeout()
Channel	getChannel()
int	getChannelSendOptions()
ClassLoader[]	getExternalLoaders()
AbstractReplicatedMap.MapEntry	getInternal(Object key)
byte[]	getMapContextName()
Member[]	getMapMembers(HashMap members)
Member[]	getMapMembers()
Member[]	getMapMembersExcl(Member[] exclude)
AbstractReplicatedMap.MapOwner	getMapOwner()
int	getNextBackupIndex()
Member	getNextBackupNode()
RpcChannel	getRpcChannel()
long	getRpcTimeout()
protected abstract int	getStateMessageType()
Object	getStateMutex()
int	hashCode()
void	heartbeat()
protected void	init(AbstractReplicatedMap.MapOwner owner, Channel channel, String mapContextName, long timeout, int channelSendOptions, ClassLoader[] cls) Initializes the map by creating the RPC channel, registering itself as a channel listener This method is also responsible for initiating the state transfer
boolean	inSet(Member m, Member[] set)
boolean	isEmpty()
boolean	isStateTransferred()
Set	keySet()
Set	keySetFull()
void	leftOver(Serializable msg, Member sender) If the reply has already been sent to the requesting thread, the rpc callback can handle any data that comes in after the fact.
void	mapMemberAdded(Member member)
void	memberAdded(Member member)
protected void	memberAlive(Member member) We have received a member alive notification
void	memberDisappeared(Member member)
void	messageReceived(Serializable msg, Member sender)
protected void	ping(long timeout) Sends a ping out to all the members in the cluster, not just map members that this map is alive.
protected void	printMap(String header)
protected abstract Member[]	publishEntryInfo(Object key, Object value)
Object	put(Object key, Object value)
Object	put(Object key, Object value, boolean notify)
void	putAll(Map m) Copies all values from one map to this instance
Object	remove(Object key) Removes an object from this map, it will also remove it from
Object	remove(Object key, boolean notify)
protected boolean	removeEldestEntry(Entry eldest)
void	replicate(Object key, boolean complete) Replicates any changes to the object since the last time The object has to be primary, ie, if the object is a proxy or a backup, it will not be replicated
void	replicate(boolean complete) This can be invoked by a periodic thread to replicate out any changes.
Serializable	replyRequest(Serializable msg, Member sender)
void	setAccessTimeout(long accessTimeout)
void	setChannelSendOptions(int channelSendOptions)
void	setExternalLoaders(ClassLoader[] externalLoaders)
void	setMapOwner(AbstractReplicatedMap.MapOwner mapOwner)
int	size()
int	sizeFull()
void	transferState()
Collection	values()
protected Member[]	wrap(Member m) Helper methods, wraps a single member in an array

Field Detail

accessTimeout

protected transient long accessTimeout

Since the map keeps internal membership this is the timeout for a ping message to be responded to If a remote map doesn't respond within this timeframe, its considered dead.

channel

protected transient Channel channel

Reference to the channel for sending messages

channelSendOptions

protected transient int channelSendOptions

Our default send options

currentNode

protected transient int currentNode

The node we are currently backing up data to, this index will rotate on a round robin basis

DEFAULT_INITIAL_CAPACITY

public static final int DEFAULT_INITIAL_CAPACITY

The default initial capacity - MUST be a power of two.

DEFAULT_LOAD_FACTOR

public static final float DEFAULT_LOAD_FACTOR

The load factor used when none specified in constructor.

externalLoaders

protected transient ClassLoader[] externalLoaders

External class loaders if serialization and deserialization is to be performed successfully.

mapContextName

protected transient byte[] mapContextName

The Map context name makes this map unique, this allows us to have more than one map shared through one channel

mapMembers

protected transient HashMap mapMembers

A list of members in our map

mapname

protected transient String mapname

Readable string of the mapContextName value

mapOwner

protected transient AbstractReplicatedMap.MapOwner mapOwner

The owner of this map, ala a SessionManager for example

rpcChannel

protected transient RpcChannel rpcChannel

The RpcChannel to send RPC messages through

rpcTimeout

protected transient long rpcTimeout

Timeout for RPC messages, how long we will wait for a reply

stateMutex

protected transient Object stateMutex

Simple lock object for transfers

stateTransferred

protected transient boolean stateTransferred

Has the state been transferred

public AbstractReplicatedMap(AbstractReplicatedMap.MapOwner owner, Channel channel, long timeout, String mapContextName, int initialCapacity, float loadFactor, int channelSendOptions, ClassLoader[] cls)

Creates a new map

Parameters: channel The channel to use for communication timeout long - timeout for RPC messags mapContextName String - unique name for this map, to allow multiple maps per channel initialCapacity int - the size of this map, see HashMap loadFactor float - load factor, see HashMap cls - a list of classloaders to be used for deserialization of objects.

Method Detail

accept

public boolean accept(Serializable msg, Member sender)

breakdown

public void breakdown()

broadcast

protected void broadcast(int msgtype, boolean rpc)

Helper method to broadcast a message to all members in a channel

Parameters: msgtype int rpc boolean

Throws: ChannelException

clear

public void clear()

clear

public void clear(boolean notify)

clone

public Object clone()

containsKey

public boolean containsKey(Object key)

Returns true if the key has an entry in the map. The entry can be a proxy or a backup entry, invoking get(key) will make this entry primary for the group

Parameters: key Object

Returns: boolean

containsValue

public boolean containsValue(Object value)

entrySet

public Set entrySet()

entrySetFull

public Set entrySetFull()

Returns the entire contents of the map Map.Entry.getValue() will return a LazyReplicatedMap.MapEntry object containing all the information about the object.

Returns: Set

equals

public boolean equals(Object o)

excludeFromSet

public Member[] excludeFromSet(Member[] mbrs, Member[] set)

finalize

public void finalize()

get

public Object get(Object key)

getAccessTimeout

public long getAccessTimeout()

getChannel

public Channel getChannel()

getChannelSendOptions

public int getChannelSendOptions()

getExternalLoaders

public ClassLoader[] getExternalLoaders()

getInternal

public AbstractReplicatedMap.MapEntry getInternal(Object key)

getMapContextName

public byte[] getMapContextName()

getMapMembers

public Member[] getMapMembers(HashMap members)

getMapMembers

public Member[] getMapMembers()

getMapMembersExcl

public Member[] getMapMembersExcl(Member[] exclude)

getMapOwner

public AbstractReplicatedMap.MapOwner getMapOwner()

getNextBackupIndex

public int getNextBackupIndex()

getNextBackupNode

public Member getNextBackupNode()

getRpcChannel

public RpcChannel getRpcChannel()

getRpcTimeout

public long getRpcTimeout()

getStateMessageType

protected abstract int getStateMessageType()

getStateMutex

public Object getStateMutex()

hashCode

public int hashCode()

heartbeat

public void heartbeat()

init

protected void init(AbstractReplicatedMap.MapOwner owner, Channel channel, String mapContextName, long timeout, int channelSendOptions, ClassLoader[] cls)

Initializes the map by creating the RPC channel, registering itself as a channel listener This method is also responsible for initiating the state transfer

Parameters: owner Object channel Channel mapContextName String timeout long channelSendOptions int cls ClassLoader[]

inSet

public boolean inSet(Member m, Member[] set)

isEmpty

public boolean isEmpty()

isStateTransferred

public boolean isStateTransferred()

keySet

public Set keySet()

keySetFull

public Set keySetFull()

leftOver

public void leftOver(Serializable msg, Member sender)

If the reply has already been sent to the requesting thread, the rpc callback can handle any data that comes in after the fact.

Parameters: msg Serializable sender Member

mapMemberAdded

public void mapMemberAdded(Member member)

memberAdded

public void memberAdded(Member member)

memberAlive

protected void memberAlive(Member member)

We have received a member alive notification

Parameters: member Member

memberDisappeared

public void memberDisappeared(Member member)

messageReceived

public void messageReceived(Serializable msg, Member sender)

ping

protected void ping(long timeout)

Sends a ping out to all the members in the cluster, not just map members that this map is alive.

Parameters: timeout long

Throws: ChannelException

printMap

protected void printMap(String header)

publishEntryInfo

protected abstract Member[] publishEntryInfo(Object key, Object value)

put

public Object put(Object key, Object value)

put

public Object put(Object key, Object value, boolean notify)

putAll

public void putAll(Map m)

Copies all values from one map to this instance

Parameters: m Map

remove

public Object remove(Object key)

Removes an object from this map, it will also remove it from

Parameters: key Object

Returns: Object

remove

public Object remove(Object key, boolean notify)

removeEldestEntry

protected boolean removeEldestEntry(Entry eldest)

replicate

public void replicate(Object key, boolean complete)

Replicates any changes to the object since the last time The object has to be primary, ie, if the object is a proxy or a backup, it will not be replicated

Parameters: complete - if set to true, the object is replicated to its backup if set to false, only objects that implement ReplicatedMapEntry and the isDirty() returns true will be replicated

replicate

public void replicate(boolean complete)

This can be invoked by a periodic thread to replicate out any changes. For maps that don't store objects that implement ReplicatedMapEntry, this method should be used infrequently to avoid large amounts of data transfer

Parameters: complete boolean

replyRequest

public Serializable replyRequest(Serializable msg, Member sender)

Parameters: msg Serializable

Returns: Serializable - null if no reply should be sent

UNKNOWN: implement state transfer

Parameters: m Member

Returns: Member[]