Package org.yamcs.tctm

Class UdpParameterDataLink

java.lang.Object

com.google.common.util.concurrent.AbstractService

org.yamcs.tctm.AbstractLink

org.yamcs.tctm.AbstractParameterDataLink

org.yamcs.tctm.UdpParameterDataLink

All Implemented Interfaces:

com.google.common.util.concurrent.Service, Runnable, SystemParametersProducer, Link, LinkActionProvider, ParameterDataLink

public class UdpParameterDataLink
extends AbstractParameterDataLink
implements Runnable

Receives PP data via UDP. The UDP packets are protobuf encoded ParameterData. We don't use any checksum, assume it's done by UDP.

Nested Class Summary

Nested classes/interfaces inherited from interface org.yamcs.tctm.Link

Link.Status

Nested classes/interfaces inherited from interface com.google.common.util.concurrent.Service

com.google.common.util.concurrent.Service.Listener, com.google.common.util.concurrent.Service.State

Field Summary

Fields inherited from class org.yamcs.tctm.AbstractParameterDataLink

parameterCount

Fields inherited from class org.yamcs.tctm.AbstractLink

config, dataInCount, dataOutCount, disabled, eventProducer, LINK_NAMESPACE, linkName, log, timeService, yamcsInstance

Constructor Summary

Constructors

Constructor	Description
UdpParameterDataLink()

Method Summary

Modifier and Type	Method	Description
Link.Status	connectionStatus()	In case the link should be connected (i.e. is running and enabled) this method is called to return the actual connection status
Pvalue.ParameterData	decodeDatagram(byte[] data, int offset, int length)	Decode Pvalue.ParameterData from the content of a single received UDP Datagram.
protected void	doDisable()
protected void	doEnable()
protected void	doStart()
protected void	doStop()
String	getDetailedStatus()	Returns a short detail status (one-line)
Map<String,Object>	getExtraInfo()	Returns structured information, specific to the link.
Pvalue.ParameterData	getNextData()	Called to retrieve the next packet.
Spec	getSpec()	Returns the valid configuration of the input args of this link.
void	init(String instance, String name, YConfiguration config)	Called at startup to initialize the link.
void	resetCounters()
void	run()

Methods inherited from class org.yamcs.tctm.AbstractParameterDataLink

collectSystemParameters, getDataInCount, getDataOutCount, setParameterSink, setupSystemParameters, updateParameters

Methods inherited from class org.yamcs.tctm.AbstractLink

addAction, dataIn, dataOut, disable, enable, getAction, getActions, getConfig, getCurrentTime, getEventLoop, getLinkStatus, getName, getParent, getSystemParameters, getYamcsInstance, isDisabled, isRunningAndEnabled, setParent

Methods inherited from class com.google.common.util.concurrent.AbstractService

addListener, awaitRunning, awaitRunning, awaitRunning, awaitTerminated, awaitTerminated, awaitTerminated, doCancelStart, failureCause, isRunning, notifyFailed, notifyStarted, notifyStopped, startAsync, state, stopAsync, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.yamcs.tctm.Link

disable, enable, getConfig, getDefaultSpec, getLinkStatus, getName, getParent, isDisabled, isEffectivelyDisabled, setParent

Methods inherited from interface org.yamcs.tctm.ParameterDataLink

isParameterDataLinkImplemented

Methods inherited from interface org.yamcs.parameter.SystemParametersProducer

getFrequency

Constructor Details

UdpParameterDataLink

public UdpParameterDataLink()

Method Details

getSpec

public Spec getSpec()

Description copied from interface: Link

Returns the valid configuration of the input args of this link.

Specified by:

getSpec in interface Link

Returns:

the argument specification, or null if the args should not be validated.

init

public void init(String instance,
 String name,
 YConfiguration config)

Description copied from interface: Link

Called at startup to initialize the link.

The config corresponds to the map that is under the link definition in yamcs.instance.yaml.

Specified by:

init in interface Link

Overrides:

init in class AbstractLink

config - - the configuration - cannot be null (but can be empty)

doStart

protected void doStart()

Specified by:

doStart in class com.google.common.util.concurrent.AbstractService

doStop

protected void doStop()

Specified by:

doStop in class com.google.common.util.concurrent.AbstractService

run

public void run()

Specified by:

run in interface Runnable

getNextData

public Pvalue.ParameterData getNextData()

Called to retrieve the next packet. It blocks in reading on the UDP socket.

Returns:

anything that looks as a valid packet, just the size is taken into account to decide if it's valid or not

decodeDatagram

public Pvalue.ParameterData decodeDatagram(byte[] data,
 int offset,
 int length)
                                    throws IOException

Decode Pvalue.ParameterData from the content of a single received UDP Datagram.

UdpParameterDataLink has configurable support for either Protobuf or JSON-encoded data. Extending links may provide a custom decoder by overriding this method.

Parameters:

data - data buffer. The data received starts from offset and runs for length long.

offset - offset of the data received

length - length of the data received

Throws:

IOException

connectionStatus

public Link.Status connectionStatus()

Description copied from class: AbstractLink

In case the link should be connected (i.e. is running and enabled) this method is called to return the actual connection status

Specified by:

connectionStatus in class AbstractLink

getDetailedStatus

public String getDetailedStatus()

Description copied from interface: Link

Returns a short detail status (one-line)

Specified by:

getDetailedStatus in interface Link

Overrides:

getDetailedStatus in class AbstractLink

getExtraInfo

public Map<String,Object> getExtraInfo()

Description copied from interface: Link

Returns structured information, specific to the link.

Specified by:

getExtraInfo in interface Link

doEnable

protected void doEnable()
                 throws Exception

Overrides:

doEnable in class AbstractLink

Throws:

Exception

doDisable

protected void doDisable()
                  throws Exception

Overrides:

doDisable in class AbstractLink

Throws:

Exception

resetCounters

public void resetCounters()

Specified by:

resetCounters in interface Link

Overrides:

resetCounters in class AbstractParameterDataLink