rice.scribe
Interface IScribeApp

All Known Implementing Classes:

BasicScribeRegrTestApp, DirectScribeMaintenanceTestApp, DistScribeRegrTestApp

public interface IScribeApp

Method Summary

boolean	anycastHandler(ScribeMessage msg) Invoked by underlying scribe when it receives a anycast Message, to check if there is a local application which can take care of this anycast message.
void	faultHandler(ScribeMessage msg, NodeHandle faultyParent) Invoked by Scribe just before the "repair" SUBSCRIBE message is sent when a node suspects its parent is faulty.
void	forwardHandler(ScribeMessage msg) Called by Scribe before the node forwards a message to its children in the multicast tree.
void	isNewRoot(NodeId topicId) Upcall made by scribe to registered applications to inform them that local node is now the root for some topic, and hence can take appropriate action.
void	newParent(NodeId topicId, NodeHandle newParent, java.io.Serializable data) Upcall made by scribe to the registered applications to inform them that a new parent is found for local node in the topic tree.
void	receiveMessage(ScribeMessage msg) Called by Scribe when a multicast message arrives.
void	scribeIsReady() Invoked when the underlying Scribe substrate is ready.
void	subscribeHandler(NodeId topicId, NodeHandle child, boolean wasAdded, java.io.Serializable obj) Invoked by Scribe after a child is added to or removed from one of the node's children tables.

Method Detail

scribeIsReady

public void scribeIsReady()

Invoked when the underlying Scribe substrate is ready. The Scribe substrate becomes ready as soon as the local Pastry node on which it lies is ready. In order to get this upcall it is necessary that the IScribeApp registers itself to the Scribe substrate using the registerApp() method in IScribe interface.

receiveMessage

public void receiveMessage(ScribeMessage msg)

Called by Scribe when a multicast message arrives.

Parameters:

msg - The message sent in the PUBLISH message.

forwardHandler

public void forwardHandler(ScribeMessage msg)

Called by Scribe before the node forwards a message to its children in the multicast tree.

Parameters:

msg - The message about to be forwarded.

subscribeHandler

public void subscribeHandler(NodeId topicId,
                             NodeHandle child,
                             boolean wasAdded,
                             java.io.Serializable obj)

Invoked by Scribe after a child is added to or removed from one of the node's children tables.

Parameters:

topicId - The topic for which child was added or removed.

child - The corresponding child.

wasAdded - true if child was added and false if child was removed.

obj - The additional data associated with the subscription message, SUBSCRIBE msg, sent by the "original" child, not the forwarding node.

faultHandler

public void faultHandler(ScribeMessage msg,
                         NodeHandle faultyParent)

Invoked by Scribe just before the "repair" SUBSCRIBE message is sent when a node suspects its parent is faulty.

Parameters:

msg - The SUBSCRIBE message that is sent to repair the multicast tree.

faultyParent - The suspected faulty parent.

anycastHandler

public boolean anycastHandler(ScribeMessage msg)

Invoked by underlying scribe when it receives a anycast Message, to check if there is a local application which can take care of this anycast message. If application can service the request of anycast message, the anycast message is not routed furthur(for DFS), else the anycast message will be furthur routed following DFS.

Parameters:

msg - The corresponding Anycast message

Returns:

Whether local application was able to satisfy the request of anycast message.

isNewRoot

public void isNewRoot(NodeId topicId)

Upcall made by scribe to registered applications to inform them that local node is now the root for some topic, and hence can take appropriate action.

Parameters:

topicId - The topic for which local node is the new root.

newParent

public void newParent(NodeId topicId,
                      NodeHandle newParent,
                      java.io.Serializable data)

Upcall made by scribe to the registered applications to inform them that a new parent is found for local node in the topic tree.

Parameters:

topicId - The topic for which new parent is found

newParent - The new parent

data - The data received with the ACK message.