org.jlab.coda.cMsg.RCDomain

Class RunControl

java.lang.Object

org.jlab.coda.cMsg.common.cMsgDomainAdapter

org.jlab.coda.cMsg.RCDomain.RunControl

All Implemented Interfaces:

cMsgDomainInterface

public class RunControl
extends cMsgDomainAdapter

This class implements a cMsg client in the RunControl (or RC) domain.

Version:

1.0

Author:

Carl Timmer

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
(package private) class	RunControl.Multicaster This class defines a thread to multicast a UDP packet to the RC Multicast server every second.

Field Summary

Fields

Modifier and Type	Field and Description
(package private) boolean	abandonConnection Quit a connection in progress if true.
(package private) java.util.concurrent.CountDownLatch	connectCompletion Signal to coordinate the finishing of the 3-leg connect method.
(package private) java.io.DataOutputStream	domainOut Output TCP data stream from this client to the RC server.
(package private) java.net.InetAddress	rcServerAddress RunControl server's net addresses obtained from multicast response.
(package private) int	rcTcpServerPort RunControl server's TCP listening port obtained from connect().
(package private) int	rcUdpServerPort RunControl server's UDP listening port obtained from connect().
java.util.Set<cMsgSubscription>	subscriptions Collection of all of this client's message subscriptions which are cMsgSubscription objects.
(package private) java.net.Socket	tcpSocket Socket over which to send messages to the RC server over TCP.

Fields inherited from class org.jlab.coda.cMsg.common.cMsgDomainAdapter

connected, debug, description, domain, host, name, receiving, shutdownHandler, UDL, UDLremainder

Constructor Summary

Constructors

Constructor and Description
RunControl() Constructor.

Method Summary

Modifier and Type	Method and Description
void	connect() Method to connect to the codaComponent server from this client.
void	disconnect() Method to close the connection to the domain server.
void	flush(int timeout) Does nothing in this domain.
java.lang.String	getServerHost() Get the host of the RC server that this client is connected to.
int	getServerPort() Get the TCP port of the RC server that this client is connected to.
cMsgMessage	monitor(java.lang.String command) This method is a synchronous call to receive a message containing monitoring data from the rc multicast server specified in the UDL.
(package private) void	parseUDL(java.lang.String udlRemainder) Method to parse the Universal Domain Locator (UDL) into its various components.
void	send(cMsgMessage message) Method to send a message to the domain server for further distribution.
cMsgSubscriptionHandle	subscribe(java.lang.String subject, java.lang.String type, cMsgCallbackInterface cb, java.lang.Object userObj) Method to subscribe to receive messages of a subject and type from the rc server.
void	unsubscribe(cMsgSubscriptionHandle obj) Method to unsubscribe a previous subscription to receive messages of a subject and type from the rc server.

Methods inherited from class org.jlab.coda.cMsg.common.cMsgDomainAdapter

getCurrentUDL, getDebug, getDescription, getDomain, getHost, getInfo, getName, getShutdownHandler, getUDL, getUDLRemainder, isConnected, isReceiving, sendAndGet, setDebug, setDescription, setName, setShutdownHandler, setUDL, setUDLRemainder, shutdownClients, shutdownServers, start, stop, subscribeAndGet, syncSend

Methods inherited from class java.lang.Object

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

Field Detail

abandonConnection

volatile boolean abandonConnection

Quit a connection in progress if true.

rcServerAddress

volatile java.net.InetAddress rcServerAddress

RunControl server's net addresses obtained from multicast response.

rcUdpServerPort

volatile int rcUdpServerPort

RunControl server's UDP listening port obtained from connect().

rcTcpServerPort

volatile int rcTcpServerPort

RunControl server's TCP listening port obtained from connect().

tcpSocket

java.net.Socket tcpSocket

Socket over which to send messages to the RC server over TCP.

domainOut

java.io.DataOutputStream domainOut

Output TCP data stream from this client to the RC server.

subscriptions

public java.util.Set<cMsgSubscription> subscriptions

Collection of all of this client's message subscriptions which are cMsgSubscription objects. This set is synchronized.

connectCompletion

java.util.concurrent.CountDownLatch connectCompletion

Signal to coordinate the finishing of the 3-leg connect method.

Constructor Detail

RunControl

public RunControl()

Constructor.

Method Detail

getServerHost

public java.lang.String getServerHost()

Get the host of the RC server that this client is connected to.

Specified by:

getServerHost in interface cMsgDomainInterface

Overrides:

getServerHost in class cMsgDomainAdapter

Returns:

server's host; null if unknown

getServerPort

public int getServerPort()

Get the TCP port of the RC server that this client is connected to.

Specified by:

getServerPort in interface cMsgDomainInterface

Overrides:

getServerPort in class cMsgDomainAdapter

Returns:

server's port; 0 if unknown

flush

public void flush(int timeout)
           throws cMsgException

Does nothing in this domain.

Specified by:

flush in interface cMsgDomainInterface

Overrides:

flush in class cMsgDomainAdapter

Parameters:

timeout - time in milliseconds to wait for completion

Throws:

cMsgException - never thrown

connect

public void connect()
             throws cMsgException

Method to connect to the codaComponent server from this client.

Specified by:

connect in interface cMsgDomainInterface

Overrides:

connect in class cMsgDomainAdapter

Throws:

cMsgException - if there are problems parsing the UDL or communication problems with the server(s)

monitor

public cMsgMessage monitor(java.lang.String command)
                    throws cMsgException

This method is a synchronous call to receive a message containing monitoring data from the rc multicast server specified in the UDL. In this case, the "monitoring" data is just the host on which the rc multicast server is running. It can be found by calling the cMsgMessage.getSenderHost() method of the returned message. Get the whole list of server IP addresses in the String array payload item called "IpAddresses". This is useful when trying to find the location of a particular AFECS (runcontrol) platform.

Specified by:

monitor in interface cMsgDomainInterface

Overrides:

monitor in class cMsgDomainAdapter

Parameters:

command - time in milliseconds to wait for a response to multicasts (1000 default)

Returns:

response message containing the host running the rc multicast server contacted; null if no response is found

Throws:

cMsgException - if cMsg error.

parseUDL

void parseUDL(java.lang.String udlRemainder)
       throws cMsgException

Method to parse the Universal Domain Locator (UDL) into its various components.

Runcontrol domain UDL is of the form:

cMsg:rc://<host>:<port>/<expid>?connectTO=<timeout>&ip=<address>

Remember that for this domain:

• host is required and may also be "multicast", "localhost", or in dotted decimal form

• port is optional with a default of cMsgNetworkConstants.rcMulticastPort

• the experiment id or expid is required, it is NOT taken from the environmental variable EXPID

• connectTO (optional) is the time to wait in seconds before connect returns a timeout while waiting for the rc server to send a special (tcp) concluding connect message. Defaults to 30 seconds.

• ip (optional) is ip address in dot-decimal format which the rc server or agent must use to connect to this rc client.

Parameters:

udlRemainder - partial UDL to parse

Throws:

cMsgException - if udlRemainder is null

disconnect

public void disconnect()

Method to close the connection to the domain server. This method results in this object becoming functionally useless.

Specified by:

disconnect in interface cMsgDomainInterface

Overrides:

disconnect in class cMsgDomainAdapter

send

public void send(cMsgMessage message)
          throws cMsgException

Method to send a message to the domain server for further distribution.

Specified by:

send in interface cMsgDomainInterface

Overrides:

send in class cMsgDomainAdapter

Parameters:

message - message to send

Throws:

cMsgException - if there are communication problems with the server; subject and/or type is null

subscribe

public cMsgSubscriptionHandle subscribe(java.lang.String subject,
                                        java.lang.String type,
                                        cMsgCallbackInterface cb,
                                        java.lang.Object userObj)
                                 throws cMsgException

Method to subscribe to receive messages of a subject and type from the rc server.

Specified by:

subscribe in interface cMsgDomainInterface

Overrides:

subscribe in class cMsgDomainAdapter

Parameters:

subject - message subject

type - message type

cb - callback object whose single method is called upon receiving a message of subject and type

userObj - any user-supplied object to be given to the callback method as an argument

Returns:

handle object to be used for unsubscribing

Throws:

cMsgException - if the callback, subject and/or type is null or blank; an identical subscription already exists; there are communication problems with the server

unsubscribe

public void unsubscribe(cMsgSubscriptionHandle obj)
                 throws cMsgException

Method to unsubscribe a previous subscription to receive messages of a subject and type from the rc server.

Specified by:

unsubscribe in interface cMsgDomainInterface

Overrides:

unsubscribe in class cMsgDomainAdapter

Parameters:

obj - the object returned from a subscribe call

Throws:

cMsgException - if there are communication problems with the server; object arg is null