de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController Class Reference

Inheritance diagram for de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController:

List of all members.

Classes
class	MappedList< T >
Public Types
enum	State { DISCONNECTED, INIT, CONNECTING, CONNECTED }
Public Member Functions
	SXEController (ISXERecordFactory factory)
DocumentRecord	getDocumentRecord ()
void	setDisconnected ()
void	clear ()
void	initNetwork (ISXETransmitter transmitter)
void	startSession ()
void	startSession (SXEMessage message)
void	executeRemoteRecords (SXEMessage message)
final void	executeAndCommit (List< IRecord > records)
void	commitRecords (List< IRecord > recordsToSend)
boolean	isConnected ()
ISXETransmitter	getTransmitter ()
String	prefix ()
ISXERecordFactory	getRecordFactory ()
SXESession	getSession ()
boolean	switchToConnectingState (SXESession session)
State	getState ()
void	dispose ()
Protected Member Functions
void	initDocument ()
boolean	apply (RecordDataObject rdo)
void	applyNullRecord (SetRecord toConflict)
void	applyLocallyAndsentConflictingSetRecord (SetRecord toConflict)
boolean	handleVersionDiff (SetRecord r, boolean startSync)
void	applyQueuedRecords (IRecord cause)
boolean	apply (IRecord record)
Protected Attributes
DocumentRecord	document
ISXERecordFactory	recordFactory
SXESession	session = null
State	connectionState
ISXETransmitter	transmitter
List< SXEMessage >	queuedMessagesWhileSynchronizing = new LinkedList<SXEMessage>()
MappedList< RecordDataObject >	unappliedMissingTargetRecords = new MappedList<RecordDataObject>()
MappedList< SetRecord >	unappliedBigVersionSetRecords = new MappedList<SetRecord>()

---

Detailed Description

Central part of an SXE session that maintains the document.

To its functionalities belongs:

• maintain state of the controller during session negotiation
• applying a local list of records
• applying a remote SXE message
• queue incoming messages while synchronizing and apply them on finish
• queue out-of-order (non-causal-ready) records to apply them when possible

Author:

jurke

---

Member Enumeration Documentation

enum de::fu_berlin::inf::dpp::whiteboard::sxe::SXEController::State

Enumerator:

DISCONNECTED
INIT
CONNECTING
CONNECTED

---

Constructor & Destructor Documentation

de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.SXEController

(

ISXERecordFactory

factory

)

---

Member Function Documentation

boolean de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.apply

(

RecordDataObject

rdo

)

[protected]

This method attempts to convert a RecordDataObject to the corresponding record that will be applied then.

If a RecordDataObject is not casual ready (parent, target or predecessor SetRecord is missing), it will be queued. The only exception are SetRecords during start synchronization where missing records (==version) are expected due to possible previous conflicts.

Parameters:

rdo

Returns:

whether the RecordDataObject could be applied

boolean de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.apply

(

IRecord

record

)

[protected]

Attempts to apply the passed record. If successful it will apply all queued records that became casual ready now.

Parameters:

record

Returns:

whether the passed record could be applied

void de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.applyLocallyAndsentConflictingSetRecord

(

SetRecord

toConflict

)

[protected]

This method sends a SetRecord to all peers that conflicts with the provided one so that this will be reverted to a previous version. This may be necessary, if due to concurrent SetRecords the XML document would not be well-formed anymore due to a circular relationship.

Parameters:

toConflict

void de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.applyNullRecord

(

SetRecord

toConflict

)

[protected]

void de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.applyQueuedRecords

(

IRecord

cause

)

[protected]

Checks whether the provided record makes any queue record casual ready.

Parameters:

cause

void de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.clear

(

)

void de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.commitRecords

(

List< IRecord >

recordsToSend

)

Pack the records in a message and send it to all peers in the session

Parameters:

recordsToSend

void de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.dispose

(

)

final void de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.executeAndCommit

(

List< IRecord >

records

)

This method is to be used by commands to apply locally created records.

It will apply them, notify local listeners and if applying was successful transmit them to the peers.

Parameters:

records

void de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.executeRemoteRecords

(

SXEMessage

message

)

Attempts to apply the records of a remote message

Parameters:

message

message containing records to apply

DocumentRecord de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.getDocumentRecord

(

)

Implements de.fu_berlin.inf.dpp.whiteboard.sxe.ISXEMessageHandler.

ISXERecordFactory de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.getRecordFactory

(

)

SXESession de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.getSession

(

)

State de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.getState

(

)

ISXETransmitter de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.getTransmitter

(

)

boolean de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.handleVersionDiff	(	SetRecord	r,
		boolean	startSync
	)		[protected]

Method to take actions if a remote SetRecord has wrong version.

This may be expected behavior:

During start synchronization SetRecords may be missing (received version is too big) because they were discarded remotely due to previous conflicts.

In a session, there may arise conflicts (received version is too small).

Everything else is an error, while no action has to be taken during start synchronization but remote records must be queued to wait for the SetRecord with the missing version to arrive.

Parameters:

r
startSync

Returns:

whether the difference is handled and the record should not be applied

void de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.initDocument

(

)

[protected]

void de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.initNetwork

(

ISXETransmitter

transmitter

)

boolean de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.isConnected

(

)

String de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.prefix

(

)

void de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.setDisconnected

(

)

void de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.startSession

(

SXEMessage

message

)

Accepts a remote state and applies it to this controller, discarding the previous content.

Queues messages will be applied afterwards and the lists is cleared.

Parameters:

message

the state message

void de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.startSession

(

)

Initializes the session as host and starts to receive records from NOW.

boolean de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.switchToConnectingState

(

SXESession

session

)

Attempts to change the state to State#CONNECTING. If successful, this will initialize to receive remote records from NOW.

Parameters:

session

Returns:

whether the state change was successful

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Member Data Documentation

State de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.connectionState [protected]

DocumentRecord de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.document [protected]

List<SXEMessage> de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.queuedMessagesWhileSynchronizing = new LinkedList<SXEMessage>() [protected]

ISXERecordFactory de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.recordFactory [protected]

a factory to create custom record instances

SXESession de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.session = null [protected]

ISXETransmitter de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.transmitter [protected]

MappedList<SetRecord> de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.unappliedBigVersionSetRecords = new MappedList<SetRecord>() [protected]

A predecessor of these SetRecords is missing

MappedList<RecordDataObject> de.fu_berlin.inf.dpp.whiteboard.sxe.SXEController.unappliedMissingTargetRecords = new MappedList<RecordDataObject>() [protected]

A target of a record is missing and it is supposed to be "on the way"