org.jgroups.protocols

Class SHUFFLE

java.lang.Object

org.jgroups.stack.Protocol

org.jgroups.protocols.SHUFFLE

public class SHUFFLE
extends Protocol

Reorders messages by buffering them and shuffling the result after TIMEOUT ms.

Author:

Bela Ban

Field Summary

Fields

Modifier and Type	Field and Description
protected boolean	down
protected java.util.List<Message>	down_msgs
protected int	max_size
protected long	max_time
protected java.util.concurrent.Future<?>	task
protected TimeScheduler	timer
protected boolean	up
protected java.util.List<Message>	up_msgs

Fields inherited from class org.jgroups.stack.Protocol

after_creation_hook, down_prot, ergonomics, id, log, name, stack, stats, up_prot

Constructor Summary

Constructors

Constructor and Description
SHUFFLE()

Method Summary

Modifier and Type	Method and Description
void	destroy() This method is called on a Channel.close().
java.lang.Object	down(Event evt) An event is to be sent down the stack.
int	getMaxSize()
long	getMaxTime()
void	init() Called after instance has been created (null constructor) and before protocol is started.
boolean	isDown()
boolean	isUp()
void	setDown(boolean down)
void	setMaxSize(int max_size)
void	setMaxTime(long max_time)
void	setUp(boolean up)
protected void	startTask()
void	stop() This method is called on a Channel.disconnect().
void	stopTask()
java.lang.Object	up(Event evt) An event was received from the layer below.
void	up(MessageBatch batch) Sends up a multiple messages in a MessageBatch.

Methods inherited from class org.jgroups.stack.Protocol

accept, afterCreationHook, dumpStats, enableStats, getConfigurableObjects, getDownProtocol, getDownServices, getId, getIdsAbove, getLevel, getLog, getName, getProtocolStack, getSocketFactory, getThreadFactory, getTransport, getUpProtocol, getUpServices, getValue, isErgonomics, level, parse, printStats, providedDownServices, providedUpServices, requiredDownServices, requiredUpServices, resetStatistics, resetStats, setDownProtocol, setErgonomics, setId, setLevel, setProtocolStack, setSocketFactory, setUpProtocol, setValue, setValues, start, statsEnabled

Methods inherited from class java.lang.Object

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

Field Detail

timer

protected TimeScheduler timer

up_msgs

protected final java.util.List<Message> up_msgs

down_msgs

protected final java.util.List<Message> down_msgs

task

protected java.util.concurrent.Future<?> task

up

protected boolean up

down

protected boolean down

max_size

protected int max_size

max_time

protected long max_time

Constructor Detail

SHUFFLE

public SHUFFLE()

Method Detail

isUp

public boolean isUp()

setUp

public void setUp(boolean up)

isDown

public boolean isDown()

setDown

public void setDown(boolean down)

getMaxSize

public int getMaxSize()

setMaxSize

public void setMaxSize(int max_size)

getMaxTime

public long getMaxTime()

setMaxTime

public void setMaxTime(long max_time)

init

public void init()
          throws java.lang.Exception

Description copied from class: Protocol

Called after instance has been created (null constructor) and before protocol is started. Properties are already set. Other protocols are not yet connected and events cannot yet be sent.

Overrides:

init in class Protocol

Throws:

java.lang.Exception - Thrown if protocol cannot be initialized successfully. This will cause the ProtocolStack to fail, so the channel constructor will throw an exception

stop

public void stop()

Description copied from class: Protocol

This method is called on a Channel.disconnect(). Stops work (e.g. by closing multicast socket). Will be called from top to bottom. This means that at the time of the method invocation the neighbor protocol below is still working. This method will replace the STOP, STOP_OK, CLEANUP and CLEANUP_OK events. The ProtocolStack guarantees that when this method is called all messages in the down queue will have been flushed

Overrides:

stop in class Protocol

destroy

public void destroy()

Description copied from class: Protocol

This method is called on a Channel.close(). Does some cleanup; after the call the VM will terminate

Overrides:

destroy in class Protocol

up

public java.lang.Object up(Event evt)

Description copied from class: Protocol

An event was received from the layer below. Usually the current layer will want to examine the event type and - depending on its type - perform some computation (e.g. removing headers from a MSG event type, or updating the internal membership list when receiving a VIEW_CHANGE event). Finally the event is either a) discarded, or b) an event is sent down the stack using down_prot.down() or c) the event (or another event) is sent up the stack using up_prot.up().

Overrides:

up in class Protocol

up

public void up(MessageBatch batch)

Description copied from class: Protocol

Sends up a multiple messages in a MessageBatch. The sender of the batch is always the same, and so is the destination (null == multicast messages). Messages in a batch can be OOB messages, regular messages, or mixed messages, although the transport itself will create initial MessageBatches that contain only either OOB or regular messages.

The default processing below sends messages up the stack individually, based on a matching criteria (calling Protocol.accept(org.jgroups.Message)), and - if true - calls Protocol.up(org.jgroups.Event) for that message and removes the message. If the batch is not empty, it is passed up, or else it is dropped.

Subclasses should check if there are any messages destined for them (e.g. using MessageBatch.getMatchingMessages(short,boolean)), then possibly remove and process them and finally pass the batch up to the next protocol. Protocols can also modify messages in place, e.g. ENCRYPT could decrypt all encrypted messages in the batch, not remove them, and pass the batch up when done.

Overrides:

up in class Protocol

Parameters:

batch - The message batch

down

public java.lang.Object down(Event evt)

Description copied from class: Protocol

An event is to be sent down the stack. The layer may want to examine its type and perform some action on it, depending on the event's type. If the event is a message MSG, then the layer may need to add a header to it (or do nothing at all) before sending it down the stack using down_prot.down(). In case of a GET_ADDRESS event (which tries to retrieve the stack's address from one of the bottom layers), the layer may need to send a new response event back up the stack using up_prot.up().

Overrides:

down in class Protocol

startTask

protected void startTask()

stopTask

public void stopTask()