AIS
Class AISDataUnit

java.lang.Object
  PamguardMVC.PamDataUnit
      AIS.AISDataUnit

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, java.lang.Comparable<PamDataUnit>

public class AISDataUnit
extends PamDataUnit
implements java.io.Serializable, java.lang.Cloneable

See Also:

Serialized Form

Field Summary

protected java.lang.String	aisChannel When provided, the AIS channel is indicated as either "1" or "2." This channel indication is relative to the operating conditions of the transponder when the packet is received.
(package private) AISLocalisation	aisLocalisation
(package private) NMEABitArray	bitData
protected java.lang.String	charData Contents of the M.1371 radio message using the six-bit field type
protected java.lang.String	dataType AIVDM, etc.
protected int	fillBits Number of "fill-bits" added to complete the last six-bit character
protected boolean	isInRange Flag used when a limit is placed on range.
protected int	messageID Pulled out from the start of the AIVDM string.
private static int	MINIMUMBITS
int	mmsiNumber
protected boolean	newUnit
private static int	POSITIONREPORTBITS
private java.util.ArrayList<AISPositionReport>	positionReports
protected int	sentenceNumber Message sentence number
protected int	sequentialIdentifier The "message sequential identifier" is a number from 0 to 9 that is sequentially assigned as needed.
(package private) static long	serialVersionUID
private AISStaticData	staticData
private static int	STATICDATABITS
protected int	totalSentences Total number of sentences needed to transfer the message

Fields inherited from class PamguardMVC.PamDataUnit

absBlockIndex, channelBitmap, localisation, oLL, timeMilliseconds

Constructor Summary

AISDataUnit(long timeMilliseconds)
Constructor used in data collection - doesn't do much

AISDataUnit(long timeMillis, java.lang.String charData, int fillBits)
Constructor used when reading back from binary files.

Method Summary

void	addPositionReport(AISPositionReport positionReport)
protected AISDataUnit	clone()
boolean	decodeMessage() Decode the binary data which are currently in a character string
AISPositionReport	findPositionReport(long timeMillis)
AISPositionReport	getPositionReport()
java.util.ArrayList<AISPositionReport>	getPositionReports()
AISStaticData	getStaticData()
boolean	isComplete()
void	setStaticData(AISStaticData staticData)
void	update(AISDataUnit newAISUnit) Update an existing AIS data unit with new data.

Methods inherited from class PamguardMVC.PamDataUnit

clearUpdateCount, compareTo, getAbsBlockIndex, getChannelBitmap, getDatabaseIndex, getDatabaseUpdateOf, getDataUnitFileInformation, getGpsPosition, getLastUpdateTime, getLocalisation, getOriginLatLong, getPairAngle, getParentDataBlock, getTimeMilliseconds, getUpdateCount, setAbsBlockIndex, setChannelBitmap, setDatabaseIndex, setDatabaseUpdateOf, setDataUnitFileInformation, setLastUpdateTime, setLocalisation, setOriginLatLong, setParentDataBlock, setTimeMilliseconds, updateDataUnit

Methods inherited from class java.lang.Object

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

Field Detail

aisLocalisation

AISLocalisation aisLocalisation

serialVersionUID

static final long serialVersionUID

See Also:

Constant Field Values

isInRange

protected boolean isInRange

Flag used when a limit is placed on range. If it's clearly out of range, then this flag is set and no more updates are made from static data.

the flag can be set false again if new position data come within range.

newUnit

protected boolean newUnit

dataType

protected java.lang.String dataType

AIVDM, etc.

messageID

protected int messageID

Pulled out from the start of the AIVDM string.

totalSentences

protected int totalSentences

Total number of sentences needed to transfer the message

sentenceNumber

protected int sentenceNumber

Message sentence number

sequentialIdentifier

protected int sequentialIdentifier

The "message sequential identifier" is a number from 0 to 9 that is sequentially assigned as needed. This identifier is incremented for each new multi-sentence message. The count resets to 0, after 9 is used. For radio broadcast messages requiring multiple sentences, each sentence of the message contains the same sequential identification number. The purpose of this number is to link the separate sentences containing portions of the same radio message. This allows for the possibility that other sentences might be interleaved with the message sentences that contain the complete message contents. This number also links an ABK-sentence acknowledgement to the appropriate BBM-sentence.

aisChannel

protected java.lang.String aisChannel

When provided, the AIS channel is indicated as either "1" or "2." This channel indication is relative to the operating conditions of the transponder when the packet is received. This field shall be null when the channel identification is not provided.

charData

protected java.lang.String charData

Contents of the M.1371 radio message using the six-bit field type

The maximum string length of encapsulation is limited such that the total number of sentence characters does not exceed 82. This field supports a maximum of 62 valid characters for messages transferred using multiple sentences, and 63 valid characters for messages using a single sentence.

fillBits

protected int fillBits

Number of "fill-bits" added to complete the last six-bit character

Each character in the preceding six-bit coded character string represents six binary bits. This parameter indicates the number of bits that were added to the end of the binary packet as a result of creating the last character of the string. When the coding of the last six-bit character of the message packet does not create additional "fill-bits," this value shall be set to zero. The value "0" indicates that no "fill-bits" were added. This field may not be null.

mmsiNumber

public int mmsiNumber

positionReports

private java.util.ArrayList<AISPositionReport> positionReports

staticData

private AISStaticData staticData

bitData

transient NMEABitArray bitData

MINIMUMBITS

private static final int MINIMUMBITS

See Also:

Constant Field Values

POSITIONREPORTBITS

private static final int POSITIONREPORTBITS

See Also:

Constant Field Values

STATICDATABITS

private static final int STATICDATABITS

See Also:

Constant Field Values

Constructor Detail

AISDataUnit

public AISDataUnit(long timeMilliseconds)

Constructor used in data collection - doesn't do much

AISDataUnit

public AISDataUnit(long timeMillis,
                   java.lang.String charData,
                   int fillBits)

Constructor used when reading back from binary files.

Parameters:

timeMillis - time millis

charData - 6 bit character data string

fillBits - fill bits to ignore at end of string

Method Detail

decodeMessage

public boolean decodeMessage()

Decode the binary data which are currently in a character string

Returns:

true if the message was decoded successfully

isComplete

public boolean isComplete()

update

public void update(AISDataUnit newAISUnit)

Update an existing AIS data unit with new data.

Parameters:

newAISUnit -

clone

protected AISDataUnit clone()

Overrides:

clone in class java.lang.Object

getPositionReport

public AISPositionReport getPositionReport()

findPositionReport

public AISPositionReport findPositionReport(long timeMillis)

getStaticData

public AISStaticData getStaticData()

getPositionReports

public java.util.ArrayList<AISPositionReport> getPositionReports()

addPositionReport

public void addPositionReport(AISPositionReport positionReport)

setStaticData

public void setStaticData(AISStaticData staticData)