rice.p2p.splitstream
Class Channel

java.lang.Object
  rice.p2p.splitstream.Channel

public class Channel
extends java.lang.Object

The channel controls all the meta data associated with a group of stripes. It contains the stripes themselves, and one of the stripe is the primary stripe for this channel. A stripe whose topicId matches some prefix with local node id, then it becomes its primary stripe. A channelId uniquely identifies a channel. Number of stripes is obtained by pow(2, STRIPE_BASE), so for STRIPE_BASE = 4, it is 16. Stripe identifiers are obtained by replacing first digit by every possible value of a digit and second digit by 8. So, if channelId is <0x1AB88..>, then stripe id's generated are <0x08B88..>, <0x18B88..>, <0x28B88..> etc.

Version:

$Id: Channel.java 3613 2007-02-15 14:45:14Z jstewart $

Author:

Ansley Post, Alan Mislove, Atul Singh

Field Summary

protected ChannelId	channelId ChannelId for this channel
protected Id	localId The Id of the local node
protected Stripe[]	stripes The list of stripeIds for this channel

Constructor Summary

Channel(ChannelId channelId, Scribe scribe, java.lang.String instance, IdFactory factory, Id localId, int stripeBase, int maxFailedSubscriptions)
Constructor to create a new channel from scratch

Method Summary

protected StripeId[]	generateStripeIds(ChannelId id, IdFactory factory) Creates and returns the Ids associated with the provided channelId
ChannelId	getChannelId() Gets the channelId for this channel
Id	getLocalId() Gets the local node id.
protected Stripe	getPrimaryStripe() The primary stripe is the stripe that the user must have.
int	getStripeBase()
Stripe[]	getStripes() At any moment a node is subscribed to at least 1 but possibly more stripes.

Methods inherited from class java.lang.Object

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

Field Detail

channelId

protected ChannelId channelId

ChannelId for this channel

stripes

protected Stripe[] stripes

The list of stripeIds for this channel

localId

protected Id localId

The Id of the local node

Constructor Detail

Channel

public Channel(ChannelId channelId,
               Scribe scribe,
               java.lang.String instance,
               IdFactory factory,
               Id localId,
               int stripeBase,
               int maxFailedSubscriptions)

Constructor to create a new channel from scratch

Parameters:

channelId - The Id of the channel

scribe - The underlying stripe object

factory - The Id factory

localId - The local Id

Method Detail

getLocalId

public Id getLocalId()

Gets the local node id.

Returns:

The local node id

getChannelId

public ChannelId getChannelId()

Gets the channelId for this channel

Returns:

ChannelId the channelId for this channel

getStripes

public Stripe[] getStripes()

At any moment a node is subscribed to at least 1 but possibly more stripes. They will always be subscribed to their primary Stripe.

Returns:

Vector the Stripes this node is subscribed to.

getPrimaryStripe

protected Stripe getPrimaryStripe()

The primary stripe is the stripe that the user must have.

Returns:

Stripe The Stripe object that is the primary stripe.

getStripeBase

public int getStripeBase()

generateStripeIds

protected StripeId[] generateStripeIds(ChannelId id,
                                       IdFactory factory)

Creates and returns the Ids associated with the provided channelId

Parameters:

channelId - The id of the channel

Returns:

The array of stripeIds based on this channelId