edu.virginia.cs.mng.hypercast.DT
Class DT_Message

java.lang.Object
  |
  +--edu.virginia.cs.mng.hypercast.DT.DT_Message

class DT_Message

extends java.lang.Object

implements I_Message

This class encapsulates a DT protocol message. The message contains a type (byte), a Overlay hash(int) and 4 AddressPairs. The Src and Dst AddressPairs can not both be null.

It is immutable.

Field Summary

private DT_AddressPair	CCW Logical and Physical address of the neighbor of the sender immediately counterclockwise (CCW) of the destination.
private DT_AddressPair	CW Logical and Physical address of the neighbor of the sender immediately clockwise (CW) of the destination.
private DT_AddressPair	Dst Logical and Physical address of the destination.
static byte	Goodbye A message type
static byte	HelloNeighbor A message type
static byte	HelloNotNeighbor A message type
static byte	NewNode A message type
static byte	NodePing A message type
static byte	NodePong A message type
private int	overlayHash A hash of Overlay properties.
static byte	ServerReply A message type
static byte	ServerRequest A message type
private DT_AddressPair	Src Logical and Physical address of the sender.
static byte	TestMessage A test type
private byte	Type The protocol message type.

Constructor Summary

DT_Message(byte[] A, I_UnicastAdapter adapter)
Creates a message from a byte array.

DT_Message(DT_Message A)
Copy Constructor.

DT_Message(int T, int gh, DT_AddressPair Src_arg, DT_AddressPair Dst_arg, DT_AddressPair CW_arg, DT_AddressPair CCW_arg)
Construct a new DT_Message.

Method Summary

DT_AddressPair	getCCW()
DT_LogicalAddress	getCCWLA()
I_PhysicalAddress	getCCWPA()
DT_AddressPair	getCW()
DT_LogicalAddress	getCWLA()
I_PhysicalAddress	getCWPA()
DT_AddressPair	getDst()
DT_LogicalAddress	getDstLA()
I_PhysicalAddress	getDstPA()
java.lang.String	getLabel() Returns a string dependant on the message type.
DT_AddressPair	getLeader() the same as getCW
DT_LogicalAddress	getLeaderLA()
I_PhysicalAddress	getLeaderPA()
int	getOverlayHash() Returns the overlayHash of this message.
DT_AddressPair	getSrc()
DT_LogicalAddress	getSrcLA()
I_PhysicalAddress	getSrcPA()
(package private) byte	getType() Returns the type of the message.
static DT_Message	restoreMessage(byte[] A, int[] beginValidBytes, int endValidBytes, I_UnicastAdapter adapter, int thisOverlayHash) Creates a message, if possible, from a byte array.
byte[]	toByteArray() Converts the message into a byte array for transmission.

Methods inherited from class java.lang.Object

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

Field Detail

HelloNeighbor

public static final byte HelloNeighbor

A message type

HelloNotNeighbor

public static final byte HelloNotNeighbor

A message type

Goodbye

public static final byte Goodbye

A message type

ServerRequest

public static final byte ServerRequest

A message type

ServerReply

public static final byte ServerReply

A message type

NewNode

public static final byte NewNode

A message type

NodePing

public static final byte NodePing

A message type

NodePong

public static final byte NodePong

A message type

TestMessage

public static final byte TestMessage

A test type

Type

private byte Type

The protocol message type.

overlayHash

private int overlayHash

A hash of Overlay properties. It is used to detect either conflicting Overlays or detect bad packets.

Src

private DT_AddressPair Src

Logical and Physical address of the sender.

Dst

private DT_AddressPair Dst

Logical and Physical address of the destination.

CW

private DT_AddressPair CW

Logical and Physical address of the neighbor of the sender immediately clockwise (CW) of the destination. For the LeaderIs messages, this contains the Leader's addresses.

CCW

private DT_AddressPair CCW

Logical and Physical address of the neighbor of the sender immediately counterclockwise (CCW) of the destination.

Constructor Detail

DT_Message

public DT_Message(DT_Message A)

Copy Constructor.

DT_Message

public DT_Message(int T,
                  int gh,
                  DT_AddressPair Src_arg,
                  DT_AddressPair Dst_arg,
                  DT_AddressPair CW_arg,
                  DT_AddressPair CCW_arg)

Construct a new DT_Message. For LeaderIs messages, the Leader's AddressPair should go in the place of CW.

DT_Message

public DT_Message(byte[] A,
                  I_UnicastAdapter adapter)

Creates a message from a byte array.

Parameters:

adapter - used to create new PhysicalAddress from the byte array.

Method Detail

restoreMessage

public static DT_Message restoreMessage(byte[] A,
                                        int[] beginValidBytes,
                                        int endValidBytes,
                                        I_UnicastAdapter adapter,
                                        int thisOverlayHash)

Creates a message, if possible, from a byte array. If a message is read, the value of beginValidBytes is incremented to the index of the first byte not in the message.

Parameters:

adapter - used to create new PhysicalAddress from the byte array.

toByteArray

public byte[] toByteArray()

Converts the message into a byte array for transmission.

Specified by:

toByteArray in interface I_Message

getLabel

public java.lang.String getLabel()

Returns a string dependant on the message type.

getType

byte getType()

Returns the type of the message.

getOverlayHash

public int getOverlayHash()

Returns the overlayHash of this message.

getSrcPA

public I_PhysicalAddress getSrcPA()

getDstPA

public I_PhysicalAddress getDstPA()

getCCWPA

public I_PhysicalAddress getCCWPA()

getCWPA

public I_PhysicalAddress getCWPA()

getLeaderPA

public I_PhysicalAddress getLeaderPA()

getSrcLA

public DT_LogicalAddress getSrcLA()

getDstLA

public DT_LogicalAddress getDstLA()

getCCWLA

public DT_LogicalAddress getCCWLA()

getCWLA

public DT_LogicalAddress getCWLA()

getLeaderLA

public DT_LogicalAddress getLeaderLA()

getSrc

public DT_AddressPair getSrc()

getDst

public DT_AddressPair getDst()

getCCW

public DT_AddressPair getCCW()

getCW

public DT_AddressPair getCW()

getLeader

public DT_AddressPair getLeader()

the same as getCW