org.commonreality.reality.impl

Class StateAndConnectionManager

java.lang.Object

org.commonreality.reality.impl.StateAndConnectionManager

public class StateAndConnectionManager
extends java.lang.Object

state and connection manager does just that but is centralized so that we can ensure synchronization during the connection and state change phases of a simulation's life.

previous versions that used a separate connection manager and state handler was not sufficient as state changes could occur while a connection was being established. Even more frustratingly, if two connections were established at the same time, one or the other might not get the data for the other.

Author:

harrison

Constructor Summary

Constructors

Constructor and Description
StateAndConnectionManager(IReality reality, java.util.concurrent.Executor executor)

Method Summary

Modifier and Type	Method and Description
boolean	acceptParticipant(org.apache.mina.core.session.IoSession session, ISimulationObject object, ObjectCommandHandler objectHandler) once all the participants information has been received, we officially add them to the simulation and make sure its state is consistent with the simulations
boolean	credentialsAreValid(ICredentials credentials) return true if these credentials are valid or if we are promiscuous.
long	getAcknowledgementTimeout()
IIdentifier	getActiveParticipant(ICredentials credentials) return the identifier for the participant with the provided credentials, or null
java.util.Collection<IIdentifier>	getActiveParticipants(java.util.Collection<IIdentifier> participantContainer) return all the participants that are actively connected.
java.util.Collection<org.apache.mina.core.session.IoSession>	getActiveSessions(java.util.Collection<org.apache.mina.core.session.IoSession> container) return all the active iosessions
ICredentials	getParticipantCredentials(org.apache.mina.core.session.IoSession session)
IIdentifier	getParticipantIdentifier(org.apache.mina.core.session.IoSession session)
org.apache.mina.core.session.IoSession	getParticipantSession(IIdentifier participantId) return the IoSession for the participant.
org.apache.mina.core.session.IoSession	getPendingParticipantSession(IIdentifier participantId)
java.util.concurrent.locks.ReentrantReadWriteLock	getStateLock()
void	grantCredentials(ICredentials credentials, boolean wantsClockOwnership) adds the credentials to the set of acceptable credentials.
protected boolean	isAddressingInfoValid(org.apache.mina.core.session.IoSession session, IAddressingInformation addressing) this should, ultimately, check to be sure that the location they report for connecting too is consistent with where they actually are (cheap spoofing measure)
boolean	isClockOwner(ICredentials credentials)
boolean	isPromiscuous()
void	participantConnected(org.apache.mina.core.session.IoSession session, IConnectionRequest request) called when a participant connects and asks to be added to the simulation.
IIdentifier	participantDisconnected(org.apache.mina.core.session.IoSession session) called when a participant leaves the simulation, cleanly or not
void	revokeCredentials(ICredentials credentials) revoke the credentials.
void	setAcknowledgementTimeout(long timeout)
void	setPromiscuous(boolean promiscuous) if promiscuous is true, all participants will be allowed to connect regardless of their credentials.
java.util.Collection<IIdentifier>	setState(IParticipant.State state) will send message to all participants and wait at most timeToWait milliseconds for acknowledgements from them.

Methods inherited from class java.lang.Object

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

Constructor Detail

StateAndConnectionManager

public StateAndConnectionManager(IReality reality,
                                 java.util.concurrent.Executor executor)

Method Detail

getStateLock

public java.util.concurrent.locks.ReentrantReadWriteLock getStateLock()

setAcknowledgementTimeout

public void setAcknowledgementTimeout(long timeout)

getAcknowledgementTimeout

public long getAcknowledgementTimeout()

setPromiscuous

public void setPromiscuous(boolean promiscuous)

if promiscuous is true, all participants will be allowed to connect regardless of their credentials.

Parameters:

promiscuous -

isPromiscuous

public boolean isPromiscuous()

grantCredentials

public void grantCredentials(ICredentials credentials,
                             boolean wantsClockOwnership)

adds the credentials to the set of acceptable credentials.

Parameters:

credentials -

wantsClockOwnership -

revokeCredentials

public void revokeCredentials(ICredentials credentials)

revoke the credentials. if there is a participant connected with these credentials, they will be immediately disconnected.

Parameters:

credentials -

credentialsAreValid

public boolean credentialsAreValid(ICredentials credentials)

return true if these credentials are valid or if we are promiscuous. We do not check that there is no one else using those credentials here..

Parameters:

credentials -

Returns:

isClockOwner

public boolean isClockOwner(ICredentials credentials)

getActiveParticipants

public java.util.Collection<IIdentifier> getActiveParticipants(java.util.Collection<IIdentifier> participantContainer)

return all the participants that are actively connected. These participants have all connected and sent all their participant data to reality

The container will not be cleared before insertion. If container is null, a new one is created

getActiveSessions

public java.util.Collection<org.apache.mina.core.session.IoSession> getActiveSessions(java.util.Collection<org.apache.mina.core.session.IoSession> container)

return all the active iosessions

Parameters:

container -

Returns:

getActiveParticipant

public IIdentifier getActiveParticipant(ICredentials credentials)

return the identifier for the participant with the provided credentials, or null

Parameters:

credentials -

Returns:

getParticipantSession

public org.apache.mina.core.session.IoSession getParticipantSession(IIdentifier participantId)

return the IoSession for the participant. This IIdentifier must be in the current set returned by #getActiveParticipants(), otherwise it will return null, signaling that the participant has disconnected.

getPendingParticipantSession

public org.apache.mina.core.session.IoSession getPendingParticipantSession(IIdentifier participantId)

getParticipantIdentifier

public IIdentifier getParticipantIdentifier(org.apache.mina.core.session.IoSession session)

getParticipantCredentials

public ICredentials getParticipantCredentials(org.apache.mina.core.session.IoSession session)

setState

public java.util.Collection<IIdentifier> setState(IParticipant.State state)

will send message to all participants and wait at most timeToWait milliseconds for acknowledgements from them. If some have not acknowledged by the timeToWait limit, they are returned so that other processing can be performed.
If getParticipantSession(IIdentifier) returns null for any identifier (disconnected), it will be ignored and added to the list of nonresponders.

Parameters:

participants -

message -

timeToWait - or 0 if indefinite

Returns:

collection of identifiers of participants who have not responded in time.

isAddressingInfoValid

protected boolean isAddressingInfoValid(org.apache.mina.core.session.IoSession session,
                                        IAddressingInformation addressing)

this should, ultimately, check to be sure that the location they report for connecting too is consistent with where they actually are (cheap spoofing measure)

Parameters:

session -

addressing -

Returns:

participantConnected

public void participantConnected(org.apache.mina.core.session.IoSession session,
                                 IConnectionRequest request)

called when a participant connects and asks to be added to the simulation. This will check the participant's credentials and determine whether or not to allow the connection to continue.

If the participant is allowed to connect, it wont actually be added to the simulation until after we have received all of its information. At which time, #acceptParticipant() will be called

acceptParticipant

public boolean acceptParticipant(org.apache.mina.core.session.IoSession session,
                                 ISimulationObject object,
                                 ObjectCommandHandler objectHandler)

once all the participants information has been received, we officially add them to the simulation and make sure its state is consistent with the simulations

participantDisconnected

public IIdentifier participantDisconnected(org.apache.mina.core.session.IoSession session)

called when a participant leaves the simulation, cleanly or not