cgl.narada.protocol
Class ProtocolHandler

java.lang.Object
  java.lang.Thread
      cgl.narada.protocol.ProtocolHandler

All Implemented Interfaces:

Handler, ProtocolDebugFlags, Runnable

public class ProtocolHandler
extends Thread
implements ProtocolDebugFlags, Handler

The ProtocolHandler provides the interface between the transport layer and the protocol layer. It is also designed in a way to provide an interface between the protocol layer and the application layer. This allows us to decouple the transport aspects from the protocol layer. The protocol layer thus deals only with the logical addresses associated with nodes, instead of the various transport indentifiers (TCP,UDP Multicast ) associated with any given node.

Nested Class Summary

Nested classes/interfaces inherited from class java.lang.Thread

Thread.State, Thread.UncaughtExceptionHandler

Field Summary

boolean

startForwardingService

Fields inherited from class java.lang.Thread

MAX_PRIORITY, MIN_PRIORITY, NORM_PRIORITY

Fields inherited from interface cgl.narada.protocol.ProtocolDebugFlags

BrokerLocatorCommunicator_Debug, ClientConnectionHandler_Debug, Connection_Debug, ConnectionPropagation_Debug, Destinations_Debug, DuplicateDetection_Debug, EventBuffer_Debug, EventRoutingProtocol_Debug, Gateway_Debug, GatewayInfo_Debug, GatewayPropagation_Debug, JmsProfilePropagation_Debug, LinkCostMatrix_Debug, NodeAdditionProtocol_Debug, NodeAddress_Debug, Path_Debug, PersistentEventRouting_Debug, ProfilePropagationProtocol_Debug, ProtocolException_Debug, ProtocolHandler_Debug, ProtocolID_Debug, ProtocolIDFactory_Debug, RoutingCache_Debug, RtpEventRoutingProtocol_Debug, RtpProfilePropagation_Debug, SecureMessageRouting_Debug, TagValueEventRoutingProtocol_Debug, TagValueProfilePropagation_Debug, XmlEventRoutingProtocol_Debug, XPathProfilePropagation_Debug

Constructor Summary

ProtocolHandler()

ProtocolHandler(NodeAddress nodeAddress, short[] connectionVector, int concurrentConnectionLimit, String ipDiscriminator, GatewayInfo gatewayInfo)
The protocol handler constructor.

Method Summary

void	closeCommunicationsTo(Object nodeId) Ensures communication links to the specified node are all terminated
void	closeCommunicationsTo(String nodeId)
void	closeLink(String linkId)
void	connectionToBrokerLost(Object brokerConnectionId, String _linkId)
void	connectionToClientLost(Object clientIdentifier, String linkId)
byte[]	constructGatewaySetupRequest(String node, int gatewayLevel)
byte[]	constructNodeAdditionRequest(int[] levels, boolean from) This method is response for issuing a node addition request.
void	disableMonitoring()
boolean	doSecurityChecks(NBEvent event) Handler into the secure topics manager's function to validate the contents of an NBEvent
void	enableMonitoring()
String[]	enumerateLinks()
void	garbageCollectLink(String node) Responible for garbage collecting a certain link.
void	generateReport(String report) Not been implemented so far, but will be soon and would aid as a information gathering tool.
NodeAddress	getAssignedAddress() Accessor function for retrieving the node address of the server node hosting the connectivity graph.
Destinations	getNodeDestination() Retreives the destination that has been assigned to this node.
SignedSecurityToken	getSecurityTokenForProfileId(Object key)
Hashtable	getSupportedTransportProtocols()
ProtocolID	getUniqueProtocolID() This method provides us with access to the ProtocolIDFactory which provides us with a list of unique protocol ID's
void	handleData(byte[] data, String sender)
void	initDiscoveryRequestForwardingService() Initializes the Discovery Request forwarding service
void	initDiscoveryRequestTable(int size) Initializes the Discovery Request Table with the specified size
void	initializeProtocolSuite() This method is responsible for initializing the protocol suite.
void	initSecureTopicsManager(String keyStoreFileLocation)
boolean	isClient() This method indicates that the node in question is a broker
boolean	isNodeAddressAssigned() shows whether node address is assigned
void	loadCommunicationsOfType(Properties props, String commType)
void	mapLinkToBrokerNode(String node, Gateway _newAddress, ProtocolID brokerConnectionId) This method is used, when an unassigned node has been assigned logical address by the system
void	mapLinkToClientNode(String node, Gateway _newAddress, Object clientIdentifier) This method is used, when an unassigned client node has been assigned logical address by the system
void	processBrokerDiscoveryRequest(byte[] discoBytes, boolean mustBeForwarded) Constructs and send a Broker Discovery Response Message
void	processData(byte[] data, String sender) This is the method which routes different protocol packets to the appropriate protocols in the protocol suite.
void	propagateConnectionInformation(Connection createdConnection, Gateway hop) This is invoked by the node which is responsible for issuing the Node setup response.
void	propagateProfilesAtSpecifiedLevel(Gateway hop, int level) Propagates profiles to a newly added node.
void	registerProfileSecurityToken(Object key, byte[] token)
void	routeMessageToClient(String reciever, int clientId, byte[] data)
void	run()
void	sendTo(String node, byte[] data) For communicating with a server node which hasn't been assigned a logical address so far
void	sendToNode(Gateway nodeAddress, byte[] data) This method send information over a specified hop.
void	setAsGatewayAtLevel(int level) This designates this node as a gateway at level level.
void	setAssignedAddress(NodeAddress nodeAddress) After a node address has been assigned, this method is responsible for setting the node address for the connectivity graph.
void	setBrokerDiscoveryRequestResponsePolicyHandler(String handler) Initializes the Broker Discovery Request response policy handler If the specified class cannot be instantiated, the broker defaults to the default policy (i.e.
void	setBrokerSystemEventListener(BrokerSystemEventListener brokerSystemEventListener)
void	setServiceConfigurationLocation(String configFileLocation)
String	setupLink(Properties props, String linkType)
void	shutdown()
void	startMonitoringService()
boolean	sysnopsisRepresentsSecureTopic(Object synopsis, int type)
void	unsetAsGatewayAtLevel(int level) This designates this node as a gateway at level level.
void	unsetForwardingService()
boolean	verifySignedSecurityToken(SignedSecurityToken sst)

Methods inherited from class java.lang.Thread

activeCount, checkAccess, countStackFrames, currentThread, destroy, dumpStack, enumerate, getAllStackTraces, getContextClassLoader, getDefaultUncaughtExceptionHandler, getId, getName, getPriority, getStackTrace, getState, getThreadGroup, getUncaughtExceptionHandler, holdsLock, interrupt, interrupted, isAlive, isDaemon, isInterrupted, join, join, join, resume, setContextClassLoader, setDaemon, setDefaultUncaughtExceptionHandler, setName, setPriority, setUncaughtExceptionHandler, sleep, sleep, start, stop, stop, suspend, toString, yield

Methods inherited from class java.lang.Object

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

Field Detail

startForwardingService

public boolean startForwardingService

Constructor Detail

ProtocolHandler

public ProtocolHandler()

ProtocolHandler

public ProtocolHandler(NodeAddress nodeAddress,
                       short[] connectionVector,
                       int concurrentConnectionLimit,
                       String ipDiscriminator,
                       GatewayInfo gatewayInfo)

The protocol handler constructor.

Parameters:

nodeAddress - The node address of the system.

connectionVector - The number of active connections that are allowed at a time, at each level

concurrentConnectionLimit - The limit on the number of active concurrent connections initiated by clients.

ipDiscriminator - The discriminator used to determine if a node can be part of a cluster

gatewayInfo - The connectivity graph of the hosting node.

Method Detail

setAssignedAddress

public void setAssignedAddress(NodeAddress nodeAddress)

After a node address has been assigned, this method is responsible for setting the node address for the connectivity graph.

Parameters:

nodeAddress - The node address of the server node hosting the connectivity graph

isNodeAddressAssigned

public boolean isNodeAddressAssigned()

shows whether node address is assigned

getAssignedAddress

public NodeAddress getAssignedAddress()

Accessor function for retrieving the node address of the server node hosting the connectivity graph.

Returns:

The node address of the server node.

getNodeDestination

public Destinations getNodeDestination()

Retreives the destination that has been assigned to this node. This is simply a wrapper around the node address of the server node. This is very useful in computing the destinations that have traversed by a message packet.

Returns:

The destinations correspinding to the server node.

getUniqueProtocolID

public ProtocolID getUniqueProtocolID()

This method provides us with access to the ProtocolIDFactory which provides us with a list of unique protocol ID's

Returns:

The unique ID associated with a request/response. This is a unique ID system wide.

setAsGatewayAtLevel

public void setAsGatewayAtLevel(int level)

This designates this node as a gateway at level level.

unsetForwardingService

public void unsetForwardingService()

unsetAsGatewayAtLevel

public void unsetAsGatewayAtLevel(int level)

This designates this node as a gateway at level level.

isClient

public boolean isClient()

This method indicates that the node in question is a broker

Specified by:

isClient in interface Handler

processData

public void processData(byte[] data,
                        String sender)

This is the method which routes different protocol packets to the appropriate protocols in the protocol suite. It does so by investigating the headers in the packets that have been received by any of the receiver threads. The different kind of protocol headers that this method can deal with are contained in cgl.narada.protocol.Protocol.

Parameters:

_dataReceived - The data that has been received.

garbageCollectLink

public void garbageCollectLink(String node)

Responible for garbage collecting a certain link. This would involve grabage collecting the resources associated with the link e.g. sockets, queues and the sender/receiver threads associated with that socket.

Parameters:

node - The string using which this node can communicate with a node that hasn't been assigned a logical address so far

closeCommunicationsTo

public void closeCommunicationsTo(String nodeId)

closeCommunicationsTo

public void closeCommunicationsTo(Object nodeId)

Ensures communication links to the specified node are all terminated

propagateConnectionInformation

public void propagateConnectionInformation(Connection createdConnection,
                                           Gateway hop)

This is invoked by the node which is responsible for issuing the Node setup response. This method performs the following functions

First it sends the serialized connection buffer over to the newly added node/unit.

Secondly, it adds the newly established connection to the connectivity graph.

Initiate a dissemination of the connection information through valid sub systems of the system.

Parameters:

createdConnection - The newly established connection

hop - The gateway over which this information needs to be sent over

initializeProtocolSuite

public void initializeProtocolSuite()

This method is responsible for initializing the protocol suite.

loadCommunicationsOfType

public void loadCommunicationsOfType(Properties props,
                                     String commType)
                              throws TransportException

Throws:

TransportException

setupLink

public String setupLink(Properties props,
                        String linkType)
                 throws TransportException

Throws:

TransportException

closeLink

public void closeLink(String linkId)

enumerateLinks

public String[] enumerateLinks()

shutdown

public void shutdown()

doSecurityChecks

public boolean doSecurityChecks(NBEvent event)

Handler into the secure topics manager's function to validate the contents of an NBEvent

Parameters:

event - - The event to verify

Returns:

TRUE if verified, FALSE otherwise

sysnopsisRepresentsSecureTopic

public boolean sysnopsisRepresentsSecureTopic(Object synopsis,
                                              int type)

registerProfileSecurityToken

public void registerProfileSecurityToken(Object key,
                                         byte[] token)

getSecurityTokenForProfileId

public SignedSecurityToken getSecurityTokenForProfileId(Object key)

verifySignedSecurityToken

public boolean verifySignedSecurityToken(SignedSecurityToken sst)

routeMessageToClient

public void routeMessageToClient(String reciever,
                                 int clientId,
                                 byte[] data)

sendTo

public void sendTo(String node,
                   byte[] data)

For communicating with a server node which hasn't been assigned a logical address so far

Parameters:

node - The string identifier for the server node.

data - The byte stream containing the information.

sendToNode

public void sendToNode(Gateway nodeAddress,
                       byte[] data)

This method send information over a specified hop. The information maintained in the connectivity graph is just the level, and the node address at that level

mapLinkToBrokerNode

public void mapLinkToBrokerNode(String node,
                                Gateway _newAddress,
                                ProtocolID brokerConnectionId)

This method is used, when an unassigned node has been assigned logical address by the system

Parameters:

node - The string identifier for the server node w/o the logical address

_newAddress - The newly assigned address for the node. Henceforth all communication with the node would be carried out using its logical address within the system

mapLinkToClientNode

public void mapLinkToClientNode(String node,
                                Gateway _newAddress,
                                Object clientIdentifier)

This method is used, when an unassigned client node has been assigned logical address by the system

Parameters:

node - The string identifier for the client node w/o the logical address

_newAddress - The newly assigned address for the node. Henceforth all communication with the node would be carried out using its logical address within the system.

clientIdentifier - The newly assigned identifier for the client

connectionToClientLost

public void connectionToClientLost(Object clientIdentifier,
                                   String linkId)

connectionToBrokerLost

public void connectionToBrokerLost(Object brokerConnectionId,
                                   String _linkId)

handleData

public void handleData(byte[] data,
                       String sender)

Specified by:

handleData in interface Handler

run

public void run()

Specified by:

run in interface Runnable

Overrides:

run in class Thread

generateReport

public void generateReport(String report)

Not been implemented so far, but will be soon and would aid as a information gathering tool. The information generated would be used for further optimizations.

Parameters:

report - The report being issued by various protocols. All the protocols have a reference to the protocolHandler.

constructNodeAdditionRequest

public byte[] constructNodeAdditionRequest(int[] levels,
                                           boolean from)

This method is response for issuing a node addition request.

propagateProfilesAtSpecifiedLevel

public void propagateProfilesAtSpecifiedLevel(Gateway hop,
                                              int level)

Propagates profiles to a newly added node.

Parameters:

hop -

level -

constructGatewaySetupRequest

public byte[] constructGatewaySetupRequest(String node,
                                           int gatewayLevel)

startMonitoringService

public void startMonitoringService()
                            throws TransportException

Throws:

TransportException

enableMonitoring

public void enableMonitoring()

disableMonitoring

public void disableMonitoring()

setServiceConfigurationLocation

public void setServiceConfigurationLocation(String configFileLocation)

setBrokerSystemEventListener

public final void setBrokerSystemEventListener(BrokerSystemEventListener brokerSystemEventListener)

Parameters:

brokerSystemEventListener - The brokerSystemEventListener to set.

initSecureTopicsManager

public void initSecureTopicsManager(String keyStoreFileLocation)

initDiscoveryRequestForwardingService

public void initDiscoveryRequestForwardingService()

Initializes the Discovery Request forwarding service

initDiscoveryRequestTable

public void initDiscoveryRequestTable(int size)

Initializes the Discovery Request Table with the specified size

Parameters:

size - - MAXIMUM number of entries permitted

setBrokerDiscoveryRequestResponsePolicyHandler

public void setBrokerDiscoveryRequestResponsePolicyHandler(String handler)

Initializes the Broker Discovery Request response policy handler
If the specified class cannot be instantiated, the broker defaults to the default policy (i.e. Respond to all requests)

Parameters:

handler - - String specifiying the class to load.

getSupportedTransportProtocols

public Hashtable getSupportedTransportProtocols()

processBrokerDiscoveryRequest

public void processBrokerDiscoveryRequest(byte[] discoBytes,
                                          boolean mustBeForwarded)

Constructs and send a Broker Discovery Response Message

Parameters:

discoRequest - - The bytes that make the BrokerDiscoveryRequest

mustBeForwarded - - If true, then use the BrokerDiscoveryRequest Forwarding service to forward the discovery request to other possible brokers in the network. If FALSE then we do not forward the request.