Package org.apache.qpid.protonj2.engine.impl

Class ProtonConnection

java.lang.Object

org.apache.qpid.protonj2.engine.impl.ProtonEndpoint<Connection>

org.apache.qpid.protonj2.engine.impl.ProtonConnection

All Implemented Interfaces:

Connection, Endpoint<Connection>, AMQPHeader.HeaderHandler<ProtonEngine>, Performative.PerformativeHandler<ProtonEngine>

public class ProtonConnection
extends ProtonEndpoint<Connection>
implements Connection, AMQPHeader.HeaderHandler<ProtonEngine>, Performative.PerformativeHandler<ProtonEngine>

Implements the proton Connection API

Field Summary

Fields inherited from class org.apache.qpid.protonj2.engine.impl.ProtonEndpoint

engine

Method Summary

Modifier and Type	Method	Description
ProtonConnection	close()	Close the end point locally and send the closing performative immediately if possible or holds it until the Connection / Engine state allows it.
int	getChannelMax()
String	getContainerId()
Symbol[]	getDesiredCapabilities()
String	getHostname()
long	getIdleTimeout()
long	getMaxFrameSize()
Symbol[]	getOfferedCapabilities()
Connection	getParent()	Gets the parent of this Endpoint which can be itself for Connection instance.
Map<Symbol,Object>	getProperties()
String	getRemoteContainerId()
Symbol[]	getRemoteDesiredCapabilities()
String	getRemoteHostname()
long	getRemoteIdleTimeout()
long	getRemoteMaxFrameSize()
Symbol[]	getRemoteOfferedCapabilities()
Map<Symbol,Object>	getRemoteProperties()
ConnectionState	getRemoteState()
ConnectionState	getState()
void	handleAMQPHeader(AMQPHeader header, ProtonEngine context)
void	handleAttach(Attach attach, ProtonBuffer payload, int channel, ProtonEngine context)
void	handleBegin(Begin begin, ProtonBuffer payload, int channel, ProtonEngine context)
void	handleClose(Close close, ProtonBuffer payload, int channel, ProtonEngine context)
void	handleDetach(Detach detach, ProtonBuffer payload, int channel, ProtonEngine context)
void	handleDisposition(Disposition disposition, ProtonBuffer payload, int channel, ProtonEngine context)
void	handleEnd(End end, ProtonBuffer payload, int channel, ProtonEngine context)
void	handleFlow(Flow flow, ProtonBuffer payload, int channel, ProtonEngine context)
void	handleOpen(Open open, ProtonBuffer payload, int channel, ProtonEngine context)
void	handleSASLHeader(AMQPHeader header, ProtonEngine context)
void	handleTransfer(Transfer transfer, ProtonBuffer payload, int channel, ProtonEngine context)
boolean	isLocallyClosed()	Returns true if this Endpoint is currently locally closed meaning that a call to the Endpoint.close() method has occurred.
boolean	isLocallyOpen()	Returns true if this Endpoint is currently locally open meaning that the Endpoint.open() has been called but the Endpoint.close() has not.
boolean	isRemotelyClosed()	Returns true if this Endpoint is currently remotely closed meaning that the AMQP performative that completes the close phase of this Endpoint's lifetime has arrived.
boolean	isRemotelyOpen()	Returns true if this Endpoint is currently remotely open meaning that the AMQP performative that completes the open phase of this Endpoint's lifetime has arrived but the performative that closes it has not.
Connection	negotiate()	If not already negotiated this method initiates the AMQP protocol negotiation phase of the connection process sending the AMQPHeader to the remote peer.
Connection	negotiate(EventHandler<AMQPHeader> remoteAMQPHeaderHandler)	If not already negotiated this method initiates the AMQP protocol negotiation phase of the connection process sending the AMQPHeader to the remote peer.
ProtonConnection	open()	Open the end point locally, sending the Open performative immediately if possible or holding it until SASL negotiations or the AMQP header exchange and other required performative exchanges has completed.
ProtonConnection	receiverOpenHandler(EventHandler<Receiver> remoteReceiverOpenEventHandler)	Sets a EventHandler for when an AMQP Attach frame is received from the remote peer for a receiving link.
ProtonConnection	senderOpenHandler(EventHandler<Sender> remoteSenderOpenEventHandler)	Sets a EventHandler for when an AMQP Attach frame is received from the remote peer for a sending link.
ProtonSession	session()	Creates a new Session linked to this Connection
ProtonConnection	sessionOpenHandler(EventHandler<Session> remoteSessionOpenEventHandler)	Sets a EventHandler for when an AMQP Begin frame is received from the remote peer.
Set<Session>	sessions()	Returns an unmodifiable Set of Sessions that are tracked by the Connection.
ProtonConnection	setChannelMax(int channelMax)	Set the channel max value for this Connection.
ProtonConnection	setContainerId(String containerId)	Sets the Container Id to be used when opening this Connection.
ProtonConnection	setDesiredCapabilities(Symbol... capabilities)	Sets the capabilities that are desired from the remote when this Endpoint is opened.
ProtonConnection	setHostname(String hostname)	Set the name of the host (either fully qualified or relative) to which this connection is connecting to.
ProtonConnection	setIdleTimeout(long idleTimeout)	Set the idle timeout value for this Connection.
Connection	setMaxFrameSize(long maxFrameSize)	Sets the maximum frame size allowed for this connection, which is the largest single frame that the remote can send to this Connection before it will close the connection with an error condition indicating the violation.
ProtonConnection	setOfferedCapabilities(Symbol... capabilities)	Sets the capabilities to be offered on to the remote when this Endpoint is opened.
ProtonConnection	setProperties(Map<Symbol,Object> properties)	Sets the properties to be sent to the remote when this Endpoint is Opened.
long	tick(long current)	Performs a tick operation on the connection which checks that Connection Idle timeout processing is run.
Connection	tickAuto(ScheduledExecutorService executor)	Convenience method which is the same as calling Engine.tickAuto(ScheduledExecutorService).
ProtonConnection	transactionManagerOpenHandler(EventHandler<TransactionManager> remoteTxnManagerOpenEventHandler)	Sets a EventHandler for when an AMQP Attach frame is received from the remote peer for a transaction coordination link.

Methods inherited from class org.apache.qpid.protonj2.engine.impl.ProtonEndpoint

closeHandler, engineShutdownHandler, getAttachments, getCondition, getEngine, getLinkedResource, getLinkedResource, getRemoteCondition, localCloseHandler, localOpenHandler, openHandler, setCondition, setLinkedResource

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.qpid.protonj2.engine.Endpoint

closeHandler, engineShutdownHandler, getAttachments, getCondition, getEngine, getLinkedResource, getLinkedResource, getRemoteCondition, localCloseHandler, localOpenHandler, openHandler, setCondition, setLinkedResource

Method Detail

getParent

public Connection getParent()

Description copied from interface: Endpoint

Gets the parent of this Endpoint which can be itself for Connection instance.

Specified by:

getParent in interface Connection

Specified by:

getParent in interface Endpoint<Connection>

Returns:

this Connection as it is the root of the Endpoint hierarchy.

getState

public ConnectionState getState()

Specified by:

getState in interface Connection

Returns:

the local connection state only

open

public ProtonConnection open()
                      throws EngineStateException

Description copied from interface: Endpoint

Open the end point locally, sending the Open performative immediately if possible or holding it until SASL negotiations or the AMQP header exchange and other required performative exchanges has completed. The end point will signal any registered handler of the remote opening the Connection once the remote performative that signals open completion arrives.

Specified by:

open in interface Endpoint<Connection>

Returns:

this Endpoint instance.

Throws:

EngineStateException - if an error occurs opening the Connection or the Engine is shutdown.

close

public ProtonConnection close()
                       throws EngineFailedException

Description copied from interface: Endpoint

Close the end point locally and send the closing performative immediately if possible or holds it until the Connection / Engine state allows it. If the engine encounters an error writing the performative or the engine is in a failed state from a previous error then this method will throw an exception. If the engine has been shutdown then this method will close out the local end of the Endpoint and clean up any local resources before returning normally.

Specified by:

close in interface Endpoint<Connection>

Returns:

this Endpoint instance.

Throws:

EngineFailedException - if an error occurs closing the end point or the Engine is in a failed state.

negotiate

public Connection negotiate()

Description copied from interface: Connection

If not already negotiated this method initiates the AMQP protocol negotiation phase of the connection process sending the AMQPHeader to the remote peer. For a client application this could mean requesting the server to indicate if it supports the version of the protocol this client speaks. In rare cases a server could use this to preemptively send its AMQP header. Once a header is sent the remote should respond with the AMQP Header that indicates what protocol level it supports and if there is a mismatch the the engine will be failed with a error indicating the protocol support was not successfully negotiated. If the engine has a configured SASL layer then by starting the AMQP Header exchange this will implicitly first attempt the SASL authentication step of the connection process.

Specified by:

negotiate in interface Connection

Returns:

this Connection instance.

negotiate

public Connection negotiate(EventHandler<AMQPHeader> remoteAMQPHeaderHandler)

Description copied from interface: Connection

If not already negotiated this method initiates the AMQP protocol negotiation phase of the connection process sending the AMQPHeader to the remote peer. For a client application this could mean requesting the server to indicate if it supports the version of the protocol this client speaks. In rare cases a server could use this to preemptively send its AMQP header. Once a header is sent the remote should respond with the AMQP Header that indicates what protocol level it supports and if there is a mismatch the the engine will be failed with a error indicating the protocol support was not successfully negotiated. If the engine has a configured SASL layer then by starting the AMQP Header exchange this will implicitly first attempt the SASL authentication step of the connection process. The provided remote AMQP Header handler will be called once the remote sends its AMQP Header to the either preemptively or as a response to offered AMQP Header from this peer, even if that has already happened prior to this call.

Specified by:

negotiate in interface Connection

Parameters:

remoteAMQPHeaderHandler - Handler to be called when an AMQP Header response has arrived.

Returns:

this Connection instance.

tick

public long tick(long current)

Description copied from interface: Connection

Performs a tick operation on the connection which checks that Connection Idle timeout processing is run. This method is a convenience method that delegates the work to the Engine.tick(long) method. It is an error to call this method if Connection.tickAuto(ScheduledExecutorService) was called.

Specified by:

tick in interface Connection

Parameters:

current - Current time value usually taken from System.nanoTime()

Returns:

the absolute deadline in milliseconds to next call tick by/at, or 0 if there is none.

See Also:

Engine.tick(long)

tickAuto

public Connection tickAuto(ScheduledExecutorService executor)

Description copied from interface: Connection

Convenience method which is the same as calling Engine.tickAuto(ScheduledExecutorService).

Specified by:

tickAuto in interface Connection

Parameters:

executor - The single threaded execution context where all engine work takes place.

Returns:

this Connection instance.

See Also:

Engine.tickAuto(ScheduledExecutorService)

isLocallyClosed

public boolean isLocallyClosed()

Description copied from interface: Endpoint

Returns true if this Endpoint is currently locally closed meaning that a call to the Endpoint.close() method has occurred.

Specified by:

isLocallyClosed in interface Endpoint<Connection>

Returns:

true if the Endpoint is locally closed.

See Also:

Endpoint.isLocallyOpen()

isRemotelyClosed

public boolean isRemotelyClosed()

Description copied from interface: Endpoint

Returns true if this Endpoint is currently remotely closed meaning that the AMQP performative that completes the close phase of this Endpoint's lifetime has arrived.

Specified by:

isRemotelyClosed in interface Endpoint<Connection>

Returns:

true if the Endpoint is remotely closed.

See Also:

Endpoint.isRemotelyOpen()

setContainerId

public ProtonConnection setContainerId(String containerId)

Description copied from interface: Connection

Sets the Container Id to be used when opening this Connection. The container Id can only be modified prior to a call to Endpoint.open(), once the connection has been opened locally an error will be thrown if this method is called.

Specified by:

setContainerId in interface Connection

Parameters:

containerId - The Container Id used for this end of the Connection.

Returns:

this connection.

getContainerId

public String getContainerId()

Specified by:

getContainerId in interface Connection

Returns:

the Container ID assigned to this Connection

setHostname

public ProtonConnection setHostname(String hostname)

Description copied from interface: Connection

Set the name of the host (either fully qualified or relative) to which this connection is connecting to. This information may be used by the remote peer to determine the correct back-end service to connect the client to. This value will be sent in the Open performative. Note that it is illegal to set the host name to a numeric IP address or include a port number. The host name value can only be modified prior to a call to Endpoint.open(), once the connection has been opened locally an error will be thrown if this method is called.

Specified by:

setHostname in interface Connection

Parameters:

hostname - the RFC1035 compliant host name.

Returns:

this connection.

getHostname

public String getHostname()

Specified by:

getHostname in interface Connection

Returns:

returns the host name assigned to this Connection.

See Also:

Connection.setHostname(java.lang.String)

setMaxFrameSize

public Connection setMaxFrameSize(long maxFrameSize)

Description copied from interface: Connection

Sets the maximum frame size allowed for this connection, which is the largest single frame that the remote can send to this Connection before it will close the connection with an error condition indicating the violation. The legal range for this value is defined as (512 - 2^32-1) bytes. The max frame size value can only be modified prior to a call to Endpoint.open(), once the connection has been opened locally an error will be thrown if this method is called.

Specified by:

setMaxFrameSize in interface Connection

Parameters:

maxFrameSize - The maximum number of bytes allowed for a single

Returns:

this connection.

getMaxFrameSize

public long getMaxFrameSize()

Specified by:

getMaxFrameSize in interface Connection

Returns:

the currently configured max frame size this connection will accept.

setChannelMax

public ProtonConnection setChannelMax(int channelMax)

Description copied from interface: Connection

Set the channel max value for this Connection. The channel max value can only be modified prior to a call to Endpoint.open(), once the connection has been opened locally an error will be thrown if this method is called.

Specified by:

setChannelMax in interface Connection

Parameters:

channelMax - The value to set for channel max when opening the connection.

Returns:

this connection.

getChannelMax

public int getChannelMax()

Specified by:

getChannelMax in interface Connection

Returns:

the currently configured channel max for this Connection

setIdleTimeout

public ProtonConnection setIdleTimeout(long idleTimeout)

Description copied from interface: Connection

Set the idle timeout value for this Connection. The idle timeout value can only be modified prior to a call to Endpoint.open(), once the connection has been opened locally an error will be thrown if this method is called.

Specified by:

setIdleTimeout in interface Connection

Parameters:

idleTimeout - The value to set for the idle timeout when opening the connection.

Returns:

this connection.

getIdleTimeout

public long getIdleTimeout()

Specified by:

getIdleTimeout in interface Connection

Returns:

the currently configured idle timeout for this Connection

setOfferedCapabilities

public ProtonConnection setOfferedCapabilities(Symbol... capabilities)

Description copied from interface: Endpoint

Sets the capabilities to be offered on to the remote when this Endpoint is opened. The offered capabilities value can only be modified prior to a call to Endpoint.open(), once the Endpoint has been opened locally an error will be thrown if this method is called.

Specified by:

setOfferedCapabilities in interface Endpoint<Connection>

Parameters:

capabilities - The capabilities to be offered to the remote when the Endpoint is opened.

Returns:

this Endpoint instance.

getOfferedCapabilities

public Symbol[] getOfferedCapabilities()

Specified by:

getOfferedCapabilities in interface Endpoint<Connection>

Returns:

the configured capabilities that are offered to the remote when the Endpoint is opened.

setDesiredCapabilities

public ProtonConnection setDesiredCapabilities(Symbol... capabilities)

Description copied from interface: Endpoint

Sets the capabilities that are desired from the remote when this Endpoint is opened. The desired capabilities value can only be modified prior to a call to Endpoint.open(), once the Endpoint has been opened locally an error will be thrown if this method is called.

Specified by:

setDesiredCapabilities in interface Endpoint<Connection>

Parameters:

capabilities - The capabilities desired from the remote when the Endpoint is opened.

Returns:

this Endpoint instance.

getDesiredCapabilities

public Symbol[] getDesiredCapabilities()

Specified by:

getDesiredCapabilities in interface Endpoint<Connection>

Returns:

the configured desired capabilities that are sent to the remote when the Connection is opened.

setProperties

public ProtonConnection setProperties(Map<Symbol,Object> properties)

Description copied from interface: Endpoint

Sets the properties to be sent to the remote when this Endpoint is Opened. The Endpoint properties value can only be modified prior to a call to Endpoint.open(), once the Endpoint has been opened locally an error will be thrown if this method is called.

Specified by:

setProperties in interface Endpoint<Connection>

Parameters:

properties - The properties that will be sent to the remote when this Connection is opened.

Returns:

this Endpoint instance.

getProperties

public Map<Symbol,Object> getProperties()

Specified by:

getProperties in interface Endpoint<Connection>

Returns:

the configured properties sent to the remote when this Connection is opened.

isLocallyOpen

public boolean isLocallyOpen()

Description copied from interface: Endpoint

Returns true if this Endpoint is currently locally open meaning that the Endpoint.open() has been called but the Endpoint.close() has not.

Specified by:

isLocallyOpen in interface Endpoint<Connection>

Returns:

true if the Endpoint is locally open.

See Also:

Endpoint.isLocallyClosed()

isRemotelyOpen

public boolean isRemotelyOpen()

Description copied from interface: Endpoint

Returns true if this Endpoint is currently remotely open meaning that the AMQP performative that completes the open phase of this Endpoint's lifetime has arrived but the performative that closes it has not.

Specified by:

isRemotelyOpen in interface Endpoint<Connection>

Returns:

true if the Endpoint is remotely open.

See Also:

Endpoint.isRemotelyClosed()

getRemoteContainerId

public String getRemoteContainerId()

Specified by:

getRemoteContainerId in interface Connection

Returns:

the Container Id assigned to the remote end of the Connection.

getRemoteHostname

public String getRemoteHostname()

Specified by:

getRemoteHostname in interface Connection

Returns:

the host name assigned to the remote end of this Connection.

getRemoteMaxFrameSize

public long getRemoteMaxFrameSize()

Specified by:

getRemoteMaxFrameSize in interface Connection

Returns:

the remote set max frame size limit.

getRemoteIdleTimeout

public long getRemoteIdleTimeout()

Specified by:

getRemoteIdleTimeout in interface Connection

Returns:

the idle timeout value provided by the remote end of this Connection.

getRemoteOfferedCapabilities

public Symbol[] getRemoteOfferedCapabilities()

Specified by:

getRemoteOfferedCapabilities in interface Endpoint<Connection>

Returns:

the capabilities offered by the remote when it opened its end of the Endpoint.

getRemoteDesiredCapabilities

public Symbol[] getRemoteDesiredCapabilities()

Specified by:

getRemoteDesiredCapabilities in interface Endpoint<Connection>

Returns:

the capabilities desired by the remote when it opened its end of the Endpoint.

getRemoteProperties

public Map<Symbol,Object> getRemoteProperties()

Specified by:

getRemoteProperties in interface Endpoint<Connection>

Returns:

the properties sent by the remote when it opened its end of the Endpoint.

getRemoteState

public ConnectionState getRemoteState()

Specified by:

getRemoteState in interface Connection

Returns:

the remote state (as last communicated)

session

public ProtonSession session()
                      throws IllegalStateException

Description copied from interface: Connection

Creates a new Session linked to this Connection

Specified by:

session in interface Connection

Returns:

a newly created Session linked to this Connection.

Throws:

IllegalStateException - if the Connection has already been closed.

sessions

public Set<Session> sessions()
                      throws IllegalStateException

Description copied from interface: Connection

Returns an unmodifiable Set of Sessions that are tracked by the Connection. The Session instances returned from this method will be locally or remotely open or both which gives the caller full view of the complete set of known Session instances.

Specified by:

sessions in interface Connection

Returns:

an unmodifiable Set of Sessions tracked by this Connection.

Throws:

IllegalStateException

handleAMQPHeader

public void handleAMQPHeader(AMQPHeader header,
                             ProtonEngine context)

Specified by:

handleAMQPHeader in interface AMQPHeader.HeaderHandler<ProtonEngine>

handleSASLHeader

public void handleSASLHeader(AMQPHeader header,
                             ProtonEngine context)

Specified by:

handleSASLHeader in interface AMQPHeader.HeaderHandler<ProtonEngine>

handleOpen

public void handleOpen(Open open,
                       ProtonBuffer payload,
                       int channel,
                       ProtonEngine context)

Specified by:

handleOpen in interface Performative.PerformativeHandler<ProtonEngine>

handleClose

public void handleClose(Close close,
                        ProtonBuffer payload,
                        int channel,
                        ProtonEngine context)

Specified by:

handleClose in interface Performative.PerformativeHandler<ProtonEngine>

handleBegin

public void handleBegin(Begin begin,
                        ProtonBuffer payload,
                        int channel,
                        ProtonEngine context)

Specified by:

handleBegin in interface Performative.PerformativeHandler<ProtonEngine>

handleEnd

public void handleEnd(End end,
                      ProtonBuffer payload,
                      int channel,
                      ProtonEngine context)

Specified by:

handleEnd in interface Performative.PerformativeHandler<ProtonEngine>

handleAttach

public void handleAttach(Attach attach,
                         ProtonBuffer payload,
                         int channel,
                         ProtonEngine context)

Specified by:

handleAttach in interface Performative.PerformativeHandler<ProtonEngine>

handleDetach

public void handleDetach(Detach detach,
                         ProtonBuffer payload,
                         int channel,
                         ProtonEngine context)

Specified by:

handleDetach in interface Performative.PerformativeHandler<ProtonEngine>

handleFlow

public void handleFlow(Flow flow,
                       ProtonBuffer payload,
                       int channel,
                       ProtonEngine context)

Specified by:

handleFlow in interface Performative.PerformativeHandler<ProtonEngine>

handleTransfer

public void handleTransfer(Transfer transfer,
                           ProtonBuffer payload,
                           int channel,
                           ProtonEngine context)

Specified by:

handleTransfer in interface Performative.PerformativeHandler<ProtonEngine>

handleDisposition

public void handleDisposition(Disposition disposition,
                              ProtonBuffer payload,
                              int channel,
                              ProtonEngine context)

Specified by:

handleDisposition in interface Performative.PerformativeHandler<ProtonEngine>

sessionOpenHandler

public ProtonConnection sessionOpenHandler(EventHandler<Session> remoteSessionOpenEventHandler)

Description copied from interface: Connection

Sets a EventHandler for when an AMQP Begin frame is received from the remote peer. Used to process remotely initiated Sessions. Locally initiated sessions have their own EventHandler invoked instead. This method is Typically used by servers to listen for remote Session creation.

Specified by:

sessionOpenHandler in interface Connection

Parameters:

remoteSessionOpenEventHandler - the EventHandler that will be signaled when a session is remotely opened.

Returns:

this connection

senderOpenHandler

public ProtonConnection senderOpenHandler(EventHandler<Sender> remoteSenderOpenEventHandler)

Description copied from interface: Connection

Sets a EventHandler for when an AMQP Attach frame is received from the remote peer for a sending link. Used to process remotely initiated sending link. Locally initiated links have their own EventHandler invoked instead. This method is Typically used by servers to listen for remote Receiver creation. If an event handler for remote sender open is registered on the Session that the link is owned by then that handler will be invoked instead of this one.

Specified by:

senderOpenHandler in interface Connection

Parameters:

remoteSenderOpenEventHandler - the EventHandler that will be signaled when a sender link is remotely opened.

Returns:

this connection

receiverOpenHandler

public ProtonConnection receiverOpenHandler(EventHandler<Receiver> remoteReceiverOpenEventHandler)

Description copied from interface: Connection

Sets a EventHandler for when an AMQP Attach frame is received from the remote peer for a receiving link. Used to process remotely initiated receiving link. Locally initiated links have their own EventHandler invoked instead. This method is Typically used by servers to listen for remote Sender creation. If an event handler for remote receiver open is registered on the Session that the link is owned by then that handler will be invoked instead of this one.

Specified by:

receiverOpenHandler in interface Connection

Parameters:

remoteReceiverOpenEventHandler - the EventHandler that will be signaled when a receiver link is remotely opened.

Returns:

this connection

transactionManagerOpenHandler

public ProtonConnection transactionManagerOpenHandler(EventHandler<TransactionManager> remoteTxnManagerOpenEventHandler)

Description copied from interface: Connection

Sets a EventHandler for when an AMQP Attach frame is received from the remote peer for a transaction coordination link. Used to process remotely initiated transaction manager link. Locally initiated links have their own EventHandler invoked instead. This method is Typically used by servers to listen for remote TransactionController creation. If an event handler for remote TransactionController open is registered on the Session that the link is owned by then that handler will be invoked instead of this one.

Specified by:

transactionManagerOpenHandler in interface Connection

Parameters:

remoteTxnManagerOpenEventHandler - the EventHandler that will be signaled when a TransactionController link is remotely opened.

Returns:

this connection