tapestry.ptr.impl
Class DirectMailStage

java.lang.Object
  |
  +--ostore.util.StandardStage
        |
        +--tapestry.ptr.impl.DirectMailStage

All Implemented Interfaces:

EventHandlerIF, SingleThreadedEventHandlerIF

public class DirectMailStage

extends StandardStage

implements SingleThreadedEventHandlerIF

DirectMail is mail (i.e. msg) sent out and forwarded by the DirectMailStage as a type of multicast msg that will efficiently deliver the mail to all the The DirectMailStage delivers mail efficiently to all the nodes in the system. The mail can be constrained to nodes within a certain radius (number of hops. e.g. all nodes within 2 hops of sender). At each hop, the DirectMailStage will wait for acknowledgment that the next hop has received the mail. The next hop will only send back an acknowledgement after all of its next hop's (+ 1) have sent back an acknowledgement. That is, when the original sender receives all acknowledgement, than all the nodes within the specified radius of sender have received the mail.

USAGE

To send mail, create a class that extends DirectMail and dispatch mail event.

INITIALIZATION PARAMETERS

node_id

NodeId of the local server where this stage is running.

IncludePath

Specifies if the DirectMailMsg should include path information. Flag should be false under most circumstances, unless debugging.

XactCachePollInterval

Specifies the length of time in milliseconds to keep around transaction identifiers. transaction identifiers are used to filter duplicate DirectMailMsg.

AlarmTimeout

The base period (one hop) to timeout a DirectMailMsg.

Retries

Number of times to attempt to resend a DirectMailMsg within the AlarmTimeout time.

Version:

$Id: DirectMailStage.java,v 1.1.1.1 2004/03/26 19:57:10 hweather Exp $

Author:

Hakim Weatherspoon

See Also:

DirectMail, DirectMailMsg, DirectMailAckMsg, DirectMailNackMsg, TapestryReadyMsg

Nested Class Summary

class	DirectMailStage.CheckXactCacheMsg A msg that triggers the xactCache to be cleaned.
class	DirectMailStage.NextHopState Class to hold next hop state.
class	DirectMailStage.XactKey A msg that triggers the xactCache to be cleaned.

Field Summary

Fields inherited from class ostore.util.StandardStage

classifier, DEBUG, event_types, inb_msg_types, my_node_id, my_sink, outb_msg_types, tag

Constructor Summary

DirectMailStage()

Method Summary

void	handleEvent(QueueElementIF item) Specified by seda.sandStorm.api.EventHandlerIF
void	init(ConfigDataIF config) Specified by seda.sandStorm.api.EventHandlerIF

Methods inherited from class ostore.util.StandardStage

BUG, destroy, dispatch, enqueue, handleEvents, now_ms, now_us

Methods inherited from class java.lang.Object

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

Constructor Detail

DirectMailStage

public DirectMailStage()

Method Detail

handleEvent

public void handleEvent(QueueElementIF item)
                 throws EventHandlerException

Specified by seda.sandStorm.api.EventHandlerIF

Specified by:

handleEvent in interface EventHandlerIF

EventHandlerException

init

public void init(ConfigDataIF config)
          throws Exception

Specified by seda.sandStorm.api.EventHandlerIF

Specified by:

init in interface EventHandlerIF

Overrides:

init in class StandardStage

Exception