com.northgateis.comms.dda
Class DDAMsg

java.lang.Object
 |
 +--com.northgateis.comms.dda.DDAMsg

public class DDAMsg

extends java.lang.Object

RealityX DDA Message class

This class defines a DDA message and provides various constructors and methods for accessing the fields.

See the DDATcp class for typical usage.

MAX_FUNCTION_CODE

public static final int MAX_FUNCTION_CODE

The maximimum value for a function code

MAX_REFERENCE

public static final int MAX_REFERENCE

The maximimum calue for a reference

MAX_QUALIFIER_LEN

public static final int MAX_QUALIFIER_LEN

The maximimum lenght of a qualfier array

DDAMsg

public DDAMsg()

Construct an empty DDA message

DDAMsg

public DDAMsg(int func,
 int ref,
 byte[] qualifier,
 byte[] data)

Construct a full DDA message

Parameters:

func - Integer function code in range 0 to 65535

ref - Integer reference in range 0 to 255

qualifier - Byte array containing qualifier (Max 255 bytes long)

data - Byte array containing data (Max 4G bytes long)

DDAMsg

public DDAMsg(int func,
 int ref,
 byte[] data)

Construct a DDA message with empty qualifier

Parameters:

func - Integer function code in range 0 to 65535

ref - Integer reference in range 0 to 255

data - Byte array containing data (Max 4G bytes long)

DDAMsg

public DDAMsg(int func,
 int ref)

Construct a DDA message with empty data and qualifier

Parameters:

func - Integer function code in range 0 to 65535

ref - Integer reference in range 0 to 255

setFunction

public void setFunction(int func)

Set the function code

Parameters:

func - Integer function code in range 0 to 65535

setReference

public void setReference(int ref)

Set the reference

Parameters:

ref - Integer reference in range 0 to 255

setQualifier

public void setQualifier(byte[] buf)

Set the qualifier

Parameters:

buf - Byte array containing qualifier (Max 255 bytes long)

setQualifier

public void setQualifier(java.lang.String s)

Set the qualifier

Parameters:

s - String containing qualifier (Max 255 bytes long)

setData

public void setData(byte[] buf)

Set the data block

Parameters:

buf - Byte array containing data (Max 4G bytes long)

setData

public void setData(java.lang.String s)

Set the data block

Parameters:

s - String containing data (Max 4G bytes long)

getFunction

public int getFunction()

Get the function code

Returns:

Integer function code

getReference

public int getReference()

Get the reference

Returns:

Integer reference

getQualifierLength

public int getQualifierLength()

Get the qualifier length

Returns:

Integer length of qualifier

getDataLength

public int getDataLength()

Get the data length

Returns:

Integer length of data buffer

getQualifier

public byte[] getQualifier()

Get the qualifier

Returns:

pointer to the byte array qualifier buffer

getQualifierInt

public int getQualifierInt()

Get the qualifier

Returns:

The qualifier interpreted as an ASCII integer

getData

public byte[] getData()

Get the data block

Returns:

pointer to the byte array data buffer

getBytes

public byte[] getBytes()

Serialise the message into a byte array and return it

Returns:

a new byte array containing the serialised message

build

public void build(java.io.InputStream is)
 throws java.io.IOException

Read a message from the given input stream and use it to overwrite the current message.

Parameters:

is - an input stream

Throws:

java.io.IOException - if an input or output exception occurs

toString

public java.lang.String toString()

Convert the message to a human readable format

Overrides:

toString in class java.lang.Object

Returns:

a Java String