infoservice.agreement.multicast
Class InfoserviceEMCAdapter

java.lang.Object
  infoservice.agreement.multicast.AbstractEMCAdapter
      infoservice.agreement.multicast.InfoserviceEMCAdapter

All Implemented Interfaces:

IInfoServiceAgreementAdapter, IInfoService

public class InfoserviceEMCAdapter
extends AbstractEMCAdapter
implements IInfoServiceAgreementAdapter

Author:

LERNGRUPPE An adapter for the infoservice to give them the ability to handle the agreement protocol.

Field Summary

protected java.lang.Thread	m_agreementStarter A thread which executes the agreement logic.
private DynamicCascadeConfigurator	m_dynamicMixConfigurator A cascade configurator which holds logic for wireing mixes to cascades.
(package private) java.util.Hashtable	m_infoServiceSnapshot Holds an freeze the infoservice object which are current existing as long as the agreement runs.
private MessageHandlerThread	m_messageHandler A thread which handles messages for performance reasons.
protected int	m_numberOfAllActiveInfoservices Holds the number of all infoservices and freeze it as long as the agreement runs.
private FifoQueue	m_queue A data stack which implements fifo logic used for holding messages.
(package private) InfoServiceDBEntry	m_self The database entry representation for this infoservice.

Fields inherited from class infoservice.agreement.multicast.AbstractEMCAdapter

m_activeAgreementStarted, m_agreementHandler, m_log

Constructor Summary

InfoserviceEMCAdapter()
Creates a new InfoserviceAgreementAdapter.

Method Summary

protected void	buildCascades(long l) Starts the cascade building process.
protected void	evangelizeThisInfoservice() Takes care that all infoservices know each other.
(package private) InfoServiceDBEntry	generateInfoServiceSelf() Generates an InfoServiceDBEntry for this InfoService
java.lang.String	getIdentifier() Returns a unique identifer for this infoservice.
int	getNumberOfAllInfoservices() Returns the freezed number of all infoservices which take part on the agreement protocol.
HttpResponseStructure	handleMessage(byte[] a_postData) Handles the messages coming in through the /agreement-command.
void	multicastMessage(IAgreementMessage a_message) Sends a message to all known infoservices.
protected void	prepareStart() Make sure we have "real" information about our neighbours (and they about us) once.
void	sendMessageTo(java.lang.String a_id, IAgreementMessage a_message) Sends a message to a specified infoservice.
(package private) boolean	sendToInfoService(InfoServiceDBEntry a_infoservice, IDistributable a_message) Encapsulates logic for sending a message to a infoservice.
private boolean	sendToInterface(ListenerInterface a_listener, IDistributable a_message) Encapsulates logic for sending a message to a specified listenere interface.
void	startListening() Stops the running message handler if necessary and creates a new one.

Methods inherited from class infoservice.agreement.multicast.AbstractEMCAdapter

debug, error, fatal, getLog, handleMessage, info, notifyAgreement, setIAgreementHandler, setLog, startAdapter, startAgreementCommitmentProtocol, startListeningMode, startProtocolByOperator, tryToStartAgreementHour, tryToStartAgreementMinute

Methods inherited from class java.lang.Object

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

Methods inherited from interface infoservice.agreement.IInfoServiceAgreementAdapter

startProtocolByOperator

Field Detail

m_dynamicMixConfigurator

private DynamicCascadeConfigurator m_dynamicMixConfigurator

A cascade configurator which holds logic for wireing mixes to cascades. He uses the agreement result, the common random number, to do that.

m_numberOfAllActiveInfoservices

protected int m_numberOfAllActiveInfoservices

Holds the number of all infoservices and freeze it as long as the agreement runs.

m_infoServiceSnapshot

java.util.Hashtable m_infoServiceSnapshot

Holds an freeze the infoservice object which are current existing as long as the agreement runs.

m_queue

private FifoQueue m_queue

A data stack which implements fifo logic used for holding messages.

m_self

InfoServiceDBEntry m_self

The database entry representation for this infoservice.

m_agreementStarter

protected java.lang.Thread m_agreementStarter

A thread which executes the agreement logic.

m_messageHandler

private MessageHandlerThread m_messageHandler

A thread which handles messages for performance reasons.

Constructor Detail

InfoserviceEMCAdapter

public InfoserviceEMCAdapter()

Creates a new InfoserviceAgreementAdapter. This adapter is used to connect the real InfoService to the agreement extension.

Parameters:

a_cmds - The connection object to serve network and communication.

Method Detail

generateInfoServiceSelf

InfoServiceDBEntry generateInfoServiceSelf()

Generates an InfoServiceDBEntry for this InfoService

Returns:

The InfoServiceDBEntry

evangelizeThisInfoservice

protected void evangelizeThisInfoservice()

Takes care that all infoservices know each other.

handleMessage

public HttpResponseStructure handleMessage(byte[] a_postData)

Handles the messages coming in through the /agreement-command. The a_postData is parsed to an IAgreementMessage and then put into the message queue. Messages are only accepted if an agreement is currently running or we are in the timeframe to start an new one

Specified by:

handleMessage in interface IInfoServiceAgreementAdapter

Parameters:

a_postData - The post data of the request containing an XML encoded IAgreementMessage

Returns:

HTTP_RETURN_INTERNAL_SERVER_ERROR if the message could not be parsed or the time was not right, HTTP_RETURN_OK otherwise

buildCascades

protected void buildCascades(long l)

Starts the cascade building process.

Specified by:

buildCascades in class AbstractEMCAdapter

Parameters:

l - A long value which represents the common random number.

prepareStart

protected void prepareStart()

Make sure we have "real" information about our neighbours (and they about us) once. Might not be needed in real world, but overcomes some problems at concurrent startup of multiple InfoServices (InfoServicePropagandist is too fast then and we don't want to wait 10 minutes)

Specified by:

prepareStart in class AbstractEMCAdapter

startListening

public void startListening()

Stops the running message handler if necessary and creates a new one.

Specified by:

startListening in class AbstractEMCAdapter

getNumberOfAllInfoservices

public int getNumberOfAllInfoservices()

Returns the freezed number of all infoservices which take part on the agreement protocol.

Specified by:

getNumberOfAllInfoservices in interface IInfoService

Specified by:

getNumberOfAllInfoservices in class AbstractEMCAdapter

Returns:

The number of known InfoServices

getIdentifier

public java.lang.String getIdentifier()

Returns a unique identifer for this infoservice.

Specified by:

getIdentifier in interface IInfoService

Specified by:

getIdentifier in class AbstractEMCAdapter

Returns:

An unique identifier for this IInfoService

sendMessageTo

public void sendMessageTo(java.lang.String a_id,
                          IAgreementMessage a_message)

Sends a message to a specified infoservice.

Specified by:

sendMessageTo in interface IInfoService

Specified by:

sendMessageTo in class AbstractEMCAdapter

Parameters:

a_id - The id of the receiver.

a_message - The message to send.

multicastMessage

public void multicastMessage(IAgreementMessage a_message)

Sends a message to all known infoservices.

Specified by:

multicastMessage in interface IInfoService

Specified by:

multicastMessage in class AbstractEMCAdapter

Parameters:

a_message - The message to send.

sendToInfoService

boolean sendToInfoService(InfoServiceDBEntry a_infoservice,
                          IDistributable a_message)

Encapsulates logic for sending a message to a infoservice.

Parameters:

a_infoservice - The target infoservice.

postFile -

postData -

Returns:

Success if true.

sendToInterface

private boolean sendToInterface(ListenerInterface a_listener,
                                IDistributable a_message)

Encapsulates logic for sending a message to a specified listenere interface.

Parameters:

a_listener - The network interface.

postFile -

postData -

Returns:

Success if true.