org.mbari.siam.operations.portal
Class PortalConnection

java.lang.Object
  org.mbari.siam.operations.portal.PortalConnection

public class PortalConnection
extends java.lang.Object

PortalConnection provides the interface and maintains state for one connection to a SIAM node from which data is retrieved (aka "target" node").

When Portal determines that the communications link to the target node is available, it calls attempts to "wake up" the node (which may be sleeping), and invokes PortalConnection.nodeLinkConnected() to retrieve data from the node's sensors. The retrieved packets are then distributed to shore clients, as well as saved in a file buffer. PortalConnection keeps track of which packets it has retrieved from each sensor; on subsequent retrievals it requests the "latest" data from the sensor.

PortalConnection stores client requests ("commands") until a communication link to the node is available, at which time PortalConnection sequentially forwards the requests to the node. Thus PortalConnection manages network traffic over the low-bandwidth link.

While interacting with a node on the MOOS network, the shore need only maintain a lease on the node from which data is being retrieved; the target node will ensure that any intermediate nodes/comms links are kept awake.

Author:

Bob Herlien - adapted from Portal.java

Constructor Summary

PortalConnection(java.net.InetAddress remoteAddr, java.net.InetAddress primaryAddr, Portal portal)
Construct PortalConnection for node at specified address.

Method Summary

protected boolean	connectNode() Obtain the node proxy object and get a lease.
boolean	equals(java.lang.Object o) Returns true if object is PortalConnection to same InetAddress or if object is InetAddress which equals our _targetNodeAddr
java.net.InetAddress	getInetAddress() Return InetAddress of our remote connection
Port[]	getPortConfiguration() Return descriptions of devices on node.
PortalSession	getSession() get session tracker
long	getTargetDeviceID()
long	getTargetNodeID()
int	hashCode() Return hashCode of the connection's InetAddress
boolean	nodeConnected() Returns true if portal link is active and portal has valid RMI stub to remote node
void	nodeLinkConnected() Called by portal when "link up" message received from node.
void	nodeLinkDisconnecting(long nextConnectTime) Called by node when communication link is going down.
void	nodeLinkNotify(boolean on) Notify PortalConnection that network link has come up/down
protected DevicePacketSet	retrieveData(long deviceID, long startTime, long endTime) Retrieve data from specified device, within specified time-window.
void	setSession(PortalSession session) set session tracker
void	startSession() Get node server proxy, retrieve configuration, packets, etc.
void	terminateLease() Terminate lease on the target node

Methods inherited from class java.lang.Object

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

Constructor Detail

PortalConnection

public PortalConnection(java.net.InetAddress remoteAddr,
                        java.net.InetAddress primaryAddr,
                        Portal portal)

Construct PortalConnection for node at specified address.

Parameters:

remoteAddr - Address of target node

primaryAddr -

portal - Portal which contains this connection

Method Detail

getInetAddress

public java.net.InetAddress getInetAddress()

Return InetAddress of our remote connection

equals

public boolean equals(java.lang.Object o)

Returns true if object is PortalConnection to same InetAddress or if object is InetAddress which equals our _targetNodeAddr

Overrides:

equals in class java.lang.Object

hashCode

public int hashCode()

Return hashCode of the connection's InetAddress

Overrides:

hashCode in class java.lang.Object

nodeConnected

public boolean nodeConnected()

Returns true if portal link is active and portal has valid RMI stub to remote node

getPortConfiguration

public Port[] getPortConfiguration()
                            throws UnknownConfiguration

Return descriptions of devices on node.

Throws:

UnknownConfiguration

setSession

public void setSession(PortalSession session)

set session tracker

getSession

public PortalSession getSession()

get session tracker

startSession

public void startSession()
                  throws java.lang.Exception

Get node server proxy, retrieve configuration, packets, etc.

Throws:

java.lang.Exception

nodeLinkDisconnecting

public void nodeLinkDisconnecting(long nextConnectTime)

Called by node when communication link is going down.

nodeLinkConnected

public void nodeLinkConnected()

Called by portal when "link up" message received from node.

nodeLinkNotify

public void nodeLinkNotify(boolean on)

Notify PortalConnection that network link has come up/down

connectNode

protected boolean connectNode()

Obtain the node proxy object and get a lease. Return true on success, false on error.

retrieveData

protected DevicePacketSet retrieveData(long deviceID,
                                       long startTime,
                                       long endTime)
                                throws java.rmi.RemoteException,
                                       DeviceNotFound,
                                       NoDataException,
                                       java.io.IOException,
                                       TimeoutException

Retrieve data from specified device, within specified time-window.

Throws:

java.rmi.RemoteException

DeviceNotFound

NoDataException

java.io.IOException

TimeoutException

terminateLease

public void terminateLease()
                    throws LeaseRefused,
                           java.rmi.RemoteException

Terminate lease on the target node

Throws:

LeaseRefused

java.rmi.RemoteException

getTargetNodeID

public long getTargetNodeID()

getTargetDeviceID

public long getTargetDeviceID()