org.klomp.snark

Class Message

java.lang.Object

org.klomp.snark.Message

class Message
extends Object

Represents a BitTorrent protocol message for peer communication.

This class encapsulates all BitTorrent protocol message types including:

• Control messages: keep-alive, choke, unchoke, interested, uninterested
• Piece messages: have, bitfield, request, piece, cancel
• Extension messages for protocol extensions
• Fast peer extension messages (BEP 6)
• DHT messages (BEP 5, BEP 52)

Messages are created and queued for sending through a DataOutputStream. The sendMessage() method translates messages to wire format.

Message structure includes:

• type - The message type byte
• piece - The piece index (for have, request, piece, cancel)
• begin - The offset within the piece
• length - The data length
• data - Optional payload data

See Also:

PeerState

Field Summary

Fields

Modifier and Type	Field and Description
(package private) static byte	ALLOWED_FAST
(package private) int	begin
(package private) static byte	BITFIELD
(package private) static byte	CANCEL
(package private) static byte	CHOKE
(package private) byte[]	data
(package private) static byte	EXTENSION
(package private) static byte	HASH_REJECT
(package private) static byte	HASH_REQUEST
(package private) static byte	HASHES
(package private) static byte	HAVE
(package private) static byte	HAVE_ALL
(package private) static byte	HAVE_NONE
(package private) static byte	INTERESTED
(package private) static byte	KEEP_ALIVE
(package private) int	len
(package private) int	length
(package private) int	off
(package private) int	piece
(package private) static byte	PIECE
(package private) static byte	PORT
(package private) static byte	REJECT
(package private) static byte	REQUEST
(package private) static byte	SUGGEST
(package private) byte	type
(package private) static byte	UNCHOKE
(package private) static byte	UNINTERESTED

Constructor Summary

Constructors

Constructor and Description
Message(byte type) For types KEEP_ALIVE, CHOKE, UNCHOKE, INTERESTED, UNINTERESTED, HAVE_ALL, HAVE_NONE
Message(byte[] data) For type BITFIELD
Message(byte type, int piece) For types HAVE, PORT, SUGGEST, ALLOWED_FAST
Message(byte type, int piece, int begin, int length) For types REQUEST, REJECT, CANCEL
Message(int id, byte[] data) For type EXTENSION
Message(int piece, int begin, int length, DataLoader loader) For type PIECE with deferred data

Method Summary

Modifier and Type	Method and Description
(package private) void	sendMessage(DataOutputStream dos) Utility method for sending a message through a DataStream.
String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

ALLOWED_FAST

static final byte ALLOWED_FAST

See Also:

Constant Field Values

begin

final int begin

BITFIELD

static final byte BITFIELD

See Also:

Constant Field Values

CANCEL

static final byte CANCEL

See Also:

Constant Field Values

CHOKE

static final byte CHOKE

See Also:

Constant Field Values

data

byte[] data

EXTENSION

static final byte EXTENSION

See Also:

Constant Field Values

HASH_REJECT

static final byte HASH_REJECT

See Also:

Constant Field Values

HASH_REQUEST

static final byte HASH_REQUEST

See Also:

Constant Field Values

HASHES

static final byte HASHES

See Also:

Constant Field Values

HAVE

static final byte HAVE

See Also:

Constant Field Values

HAVE_ALL

static final byte HAVE_ALL

See Also:

Constant Field Values

HAVE_NONE

static final byte HAVE_NONE

See Also:

Constant Field Values

INTERESTED

static final byte INTERESTED

See Also:

Constant Field Values

KEEP_ALIVE

static final byte KEEP_ALIVE

See Also:

Constant Field Values

len

final int len

length

final int length

off

final int off

piece

final int piece

PIECE

static final byte PIECE

See Also:

Constant Field Values

PORT

static final byte PORT

See Also:

Constant Field Values

REJECT

static final byte REJECT

See Also:

Constant Field Values

REQUEST

static final byte REQUEST

See Also:

Constant Field Values

SUGGEST

static final byte SUGGEST

See Also:

Constant Field Values

type

final byte type

UNCHOKE

static final byte UNCHOKE

See Also:

Constant Field Values

UNINTERESTED

static final byte UNINTERESTED

See Also:

Constant Field Values

Constructor Detail

Message

Message(byte type)

For types KEEP_ALIVE, CHOKE, UNCHOKE, INTERESTED, UNINTERESTED, HAVE_ALL, HAVE_NONE

Message

Message(byte[] data)

For type BITFIELD

Message

Message(byte type,
        int piece)

For types HAVE, PORT, SUGGEST, ALLOWED_FAST

Message

Message(byte type,
        int piece,
        int begin,
        int length)

For types REQUEST, REJECT, CANCEL

Message

Message(int id,
        byte[] data)

For type EXTENSION

Message

Message(int piece,
        int begin,
        int length,
        DataLoader loader)

For type PIECE with deferred data

Method Detail

sendMessage

void sendMessage(DataOutputStream dos)
          throws IOException

Utility method for sending a message through a DataStream.

Throws:

IOException

toString

public String toString()

Overrides:

toString in class Object