org.jgroups.blocks
Class ReplicatedHashtable

java.lang.Object
  java.util.Dictionary<K,V>
      java.util.Hashtable
          org.jgroups.blocks.ReplicatedHashtable

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, java.util.Map, MembershipListener, MessageListener

Deprecated. Use ReplicatedHashMap instead

public class ReplicatedHashtable
extends java.util.Hashtable
implements MessageListener, MembershipListener

Provides the abstraction of a java.util.Hashtable that is replicated at several locations. Any change to the hashtable (clear, put, remove etc) will transparently be propagated to all replicas in the group. All read-only methods will always access the local replica.

Both keys and values added to the hashtable must be serializable, the reason being that they will be sent across the network to all replicas of the group. Having said this, it is now for example possible to add RMI remote objects to the hashtable as they are derived from java.rmi.server.RemoteObject which in turn is serializable. This allows to lookup shared distributed objects by their name and invoke methods on them, regardless of one's onw location. A ReplicatedHashtable thus allows to implement a distributed naming service in just a couple of lines.

An instance of this class will contact an existing member of the group to fetch its initial state.

Contrary to DistributedHashtable, this class does not make use of RpcDispatcher (and RequestCorrelator) but uses plain asynchronous messages instead.

Author:

Bela Ban, Alfonso Olias-Sanz

See Also:

Serialized Form

Nested Class Summary

static interface	ReplicatedHashtable.Notification Deprecated.
static interface	ReplicatedHashtable.StateTransferListener Deprecated.

Field Summary

protected Log

log Deprecated.

Constructor Summary

ReplicatedHashtable(JChannel channel, long state_timeout)
Deprecated.

ReplicatedHashtable(JChannel channel, ReplicatedHashtable.StateTransferListener l, long state_timeout)
Deprecated.

ReplicatedHashtable(java.lang.String groupname, ChannelFactory factory, ReplicatedHashtable.StateTransferListener l, java.lang.String properties, long state_timeout)
Deprecated. Creates a ReplicatedHashtable

ReplicatedHashtable(java.lang.String groupname, ChannelFactory factory, java.lang.String properties, long state_timeout)
Deprecated.

Method Summary

void	_putAll(java.util.Map m) Deprecated.
void	addNotifier(ReplicatedHashtable.Notification n) Deprecated.
void	addStateTransferListener(ReplicatedHashtable.StateTransferListener l) Deprecated.
void	block() Deprecated. Block sending and receiving of messages until ViewAccepted is called
void	clear() Deprecated. Clears this hashtable so that it contains no keys
Channel	getChannel() Deprecated.
Address	getLocalAddress() Deprecated.
byte[]	getState() Deprecated. Answers the group state; e.g., when joining.
java.lang.Object	put(java.lang.Object key, java.lang.Object value) Deprecated. Maps the specified key to the specified value in the hashtable.
void	putAll(java.util.Map m) Deprecated. Copies all of the mappings from the specified Map to this Hashtable These mappings will replace any mappings that this Hashtable had for any of the keys currently in the specified Map.
void	receive(Message msg) Deprecated. Called when a message is received.
java.lang.Object	remove(java.lang.Object key) Deprecated. Removes the key (and its corresponding value) from the Hashtable.
void	removeStateTransferListener(ReplicatedHashtable.StateTransferListener l) Deprecated.
void	setState(byte[] new_state) Deprecated. Sets the group state; e.g., when joining.
boolean	stateTransferRunning() Deprecated.
void	suspect(Address suspected_mbr) Deprecated. Called when a member is suspected
void	viewAccepted(View new_view) Deprecated. Called when a change in membership has occurred.

Methods inherited from class java.util.Hashtable

clone, contains, containsKey, containsValue, elements, entrySet, equals, get, hashCode, isEmpty, keys, keySet, rehash, size, toString, values

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

log

protected final transient Log log

Deprecated.

Constructor Detail

ReplicatedHashtable

public ReplicatedHashtable(java.lang.String groupname,
                           ChannelFactory factory,
                           ReplicatedHashtable.StateTransferListener l,
                           java.lang.String properties,
                           long state_timeout)

Deprecated.

Creates a ReplicatedHashtable

Parameters:

groupname - The name of the group to join

factory - The ChannelFactory which will be used to create a channel

properties - The property string to be used to define the channel

state_timeout - The time to wait until state is retrieved in milliseconds. A value of 0 means wait forever.

ReplicatedHashtable

public ReplicatedHashtable(java.lang.String groupname,
                           ChannelFactory factory,
                           java.lang.String properties,
                           long state_timeout)

Deprecated.

ReplicatedHashtable

public ReplicatedHashtable(JChannel channel,
                           long state_timeout)
                    throws ChannelClosedException,
                           ChannelNotConnectedException

Deprecated.

Throws:

ChannelClosedException

ChannelNotConnectedException

ReplicatedHashtable

public ReplicatedHashtable(JChannel channel,
                           ReplicatedHashtable.StateTransferListener l,
                           long state_timeout)
                    throws ChannelClosedException,
                           ChannelNotConnectedException

Deprecated.

Throws:

ChannelClosedException

ChannelNotConnectedException

Method Detail

stateTransferRunning

public boolean stateTransferRunning()

Deprecated.

getLocalAddress

public Address getLocalAddress()

Deprecated.

getChannel

public Channel getChannel()

Deprecated.

addNotifier

public void addNotifier(ReplicatedHashtable.Notification n)

Deprecated.

addStateTransferListener

public final void addStateTransferListener(ReplicatedHashtable.StateTransferListener l)

Deprecated.

removeStateTransferListener

public void removeStateTransferListener(ReplicatedHashtable.StateTransferListener l)

Deprecated.

put

public java.lang.Object put(java.lang.Object key,
                            java.lang.Object value)

Deprecated.

Maps the specified key to the specified value in the hashtable. Neither of both parameters can be null

Specified by:

put in interface java.util.Map

Overrides:

put in class java.util.Hashtable

Parameters:

key - - the hashtable key

value - - the value

Returns:

the previous value of the specified key in this hashtable, or null if it did not have one

putAll

public void putAll(java.util.Map m)

Deprecated.

Copies all of the mappings from the specified Map to this Hashtable These mappings will replace any mappings that this Hashtable had for any of the keys currently in the specified Map.

Specified by:

putAll in interface java.util.Map

Overrides:

putAll in class java.util.Hashtable

Parameters:

m - - Mappings to be stored in this map

clear

public void clear()

Deprecated.

Clears this hashtable so that it contains no keys

Specified by:

clear in interface java.util.Map

Overrides:

clear in class java.util.Hashtable

remove

public java.lang.Object remove(java.lang.Object key)

Deprecated.

Removes the key (and its corresponding value) from the Hashtable.

Specified by:

remove in interface java.util.Map

Overrides:

remove in class java.util.Hashtable

Parameters:

key - - the key to be removed.

Returns:

the value to which the key had been mapped in this hashtable, or null if the key did not have a mapping.

_putAll

public void _putAll(java.util.Map m)

Deprecated.

See Also:

Map.putAll(java.util.Map)

receive

public void receive(Message msg)

Deprecated.

Description copied from interface: MessageListener

Called when a message is received.

Specified by:

receive in interface MessageListener

getState

public byte[] getState()

Deprecated.

Description copied from interface: MessageListener

Answers the group state; e.g., when joining.

Specified by:

getState in interface MessageListener

Returns:

byte[]

setState

public void setState(byte[] new_state)

Deprecated.

Description copied from interface: MessageListener

Sets the group state; e.g., when joining.

Specified by:

setState in interface MessageListener

viewAccepted

public void viewAccepted(View new_view)

Deprecated.

Description copied from interface: MembershipListener

Called when a change in membership has occurred. No long running actions or sending of messages 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)

Deprecated.

Called when a member is suspected

Specified by:

suspect in interface MembershipListener

block

public void block()

Deprecated.

Block sending and receiving of messages until ViewAccepted is called

Specified by:

block in interface MembershipListener