gps.protocol.BT
Class BTSession

java.lang.Object
  gps.protocol.BT.BTSession

All Implemented Interfaces:

SimEventHandler

public class BTSession
extends java.lang.Object
implements SimEventHandler

BT Session corresponding to a downloading or uploading session for a document.

Version:

1.2, 6/20/2005

Author:

Weishuai Yang

Field Summary

static int	COMPLETED session status - completed
static int	FAILED session status - failed
static int	MAX_ALLOWED_CONNECTION_NUM max allowed connection num
boolean	mRemoved if closed, set up the mClosed flag, and remove from hashmap
int	mStatus session status
static int	PEER_CANDIDATE_LIST_LENGTH peer candidate list length
static int	STOPPED session status - stopped
static int	WORKING session status - working

Constructor Summary

BTSession(BTTorrent t, BTPeer agent)
constructs a bt session from torrent

BTSession(java.lang.String key, BTPeer agent)
constructs a bt session from document hash key

Method Summary

boolean	addNodeHasPiece(BTPeer node, int piece) update piece information in local database
void	announcePeer(int index) let all the connected peers know that this node finishes downloading a piece.
void	announceTracker() sends announcement to tracker
void	closeConnection(BTPeer p) close connection to peer
void	connectTo(BTPeer p, boolean chokedornot) set up a connection to a peer
int	countPeersWithPiece(int i) count peers with a specific piece
BTPeer	getAgent() gets the Agent object on which this session is running
BTSocket	getConnection(BTPeer p) gets connection to a peer
java.util.LinkedHashMap	getConnections() gets connections
BTDocument	getDocument() gets document that the session is downloading/uploading
double	getDownloadBetweenSnubbingDetection() gets download amount between snubbing detection
java.util.LinkedList	getPeerCandidateList() gets candidate list
java.util.LinkedHashSet	getUnchokedList() gets unchoked list
boolean	handle(SimEvent e) process event sent to this session
void	handleConnectionTimeout(BTEvent e) handles connection time event, cuts connection
void	handlePeerMessage(BTEvent e) handles all the peer message from peers except for hand shaking.
void	handlePMBitField(BTEvent e) handles the bitfield type peer message In this simulation, bitfiled message works as the reply of handshaking this is received by the initiator, and the connection is really setup.
void	handlePMCancel(BTEvent e) handles the cancel type peer message
void	handlePMChoke(BTEvent e) handles the choke type peer message
void	handlePMHave(BTEvent e) handles the have type peer message
void	handlePMInterested(BTEvent e) handles the interested type peer message
void	handlePMNotInterested(BTEvent e) handles the notInterested type peer message
void	handlePMPiece(BTEvent e) handles the piece type peer message
void	handlePMRequest(BTEvent e) handles the request type peer message
void	handlePMUnChoke(BTEvent e) handles the unchoke type peer message
void	handleTrackerResponse(BTEvent e) process tracker response evnet
void	queryTracker() the entry point of this session, after the session is initionalized, this function is called to start the communication with tracker and peers
void	sendChoked(boolean choked, BTPeer p) send choked type peer message
void	sendInterested(boolean interested, BTPeer p) send interested type peer message
void	sendRequest(int index, BTPeer p) send request for a specific piece to a peer
void	sendRequestTo(BTPeer p) send a piece request message to a peer
void	setDownloadBetweenSnubbingDetection(double d) sets download amount between snubbing detection
void	setTorrent(BTTorrent t) set torrent for existing session
java.lang.String	toString() gets string description

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

PEER_CANDIDATE_LIST_LENGTH

public static final int PEER_CANDIDATE_LIST_LENGTH

peer candidate list length

See Also:

Constant Field Values

MAX_ALLOWED_CONNECTION_NUM

public static final int MAX_ALLOWED_CONNECTION_NUM

max allowed connection num

See Also:

Constant Field Values

WORKING

public static final int WORKING

session status - working

See Also:

Constant Field Values

COMPLETED

public static final int COMPLETED

session status - completed

See Also:

Constant Field Values

STOPPED

public static final int STOPPED

session status - stopped

See Also:

Constant Field Values

FAILED

public static final int FAILED

session status - failed

See Also:

Constant Field Values

mStatus

public int mStatus

session status

mRemoved

public boolean mRemoved

if closed, set up the mClosed flag, and remove from hashmap

Constructor Detail

BTSession

public BTSession(BTTorrent t,
                 BTPeer agent)

constructs a bt session from torrent

Parameters:

t - torrent file

agent - peer

BTSession

public BTSession(java.lang.String key,
                 BTPeer agent)

constructs a bt session from document hash key

Parameters:

key - document hash key

agent - peer

Method Detail

getAgent

public BTPeer getAgent()

gets the Agent object on which this session is running

Returns:

agent

setTorrent

public void setTorrent(BTTorrent t)

set torrent for existing session

Parameters:

t - torrent

getDocument

public BTDocument getDocument()

gets document that the session is downloading/uploading

Returns:

document object

getConnections

public java.util.LinkedHashMap getConnections()

gets connections

Returns:

hash map of connections

getConnection

public BTSocket getConnection(BTPeer p)

gets connection to a peer

Parameters:

p - peer as an index

Returns:

connection

getPeerCandidateList

public java.util.LinkedList getPeerCandidateList()

gets candidate list

Returns:

candidate list

getUnchokedList

public java.util.LinkedHashSet getUnchokedList()

gets unchoked list

Returns:

unchoked list

getDownloadBetweenSnubbingDetection

public double getDownloadBetweenSnubbingDetection()

gets download amount between snubbing detection

Returns:

download amount

setDownloadBetweenSnubbingDetection

public void setDownloadBetweenSnubbingDetection(double d)

sets download amount between snubbing detection

Parameters:

d - new download amount

handle

public boolean handle(SimEvent e)

process event sent to this session

Specified by:

handle in interface SimEventHandler

Parameters:

e - the event object with some parameters in it

Returns:

true if already handled

handleTrackerResponse

public void handleTrackerResponse(BTEvent e)

process tracker response evnet

Parameters:

e - the event object

handlePeerMessage

public void handlePeerMessage(BTEvent e)

handles all the peer message from peers except for hand shaking. hand shaking is handled by btpeer.

Parameters:

e - the event object

handleConnectionTimeout

public void handleConnectionTimeout(BTEvent e)

handles connection time event, cuts connection

Parameters:

e - the event object

handlePMBitField

public void handlePMBitField(BTEvent e)

handles the bitfield type peer message In this simulation, bitfiled message works as the reply of handshaking this is received by the initiator, and the connection is really setup.

Parameters:

e - the event object

handlePMRequest

public void handlePMRequest(BTEvent e)

handles the request type peer message

Parameters:

e - the event object

handlePMPiece

public void handlePMPiece(BTEvent e)

handles the piece type peer message

Parameters:

e - the event object

handlePMHave

public void handlePMHave(BTEvent e)

handles the have type peer message

Parameters:

e - the event object

handlePMChoke

public void handlePMChoke(BTEvent e)

handles the choke type peer message

Parameters:

e - the event object

handlePMUnChoke

public void handlePMUnChoke(BTEvent e)

handles the unchoke type peer message

Parameters:

e - the event object

handlePMInterested

public void handlePMInterested(BTEvent e)

handles the interested type peer message

Parameters:

e - the event object

handlePMNotInterested

public void handlePMNotInterested(BTEvent e)

handles the notInterested type peer message

Parameters:

e - the event object

handlePMCancel

public void handlePMCancel(BTEvent e)

handles the cancel type peer message

Parameters:

e - the event object

queryTracker

public void queryTracker()

the entry point of this session, after the session is initionalized, this function is called to start the communication with tracker and peers

announceTracker

public void announceTracker()

sends announcement to tracker

announcePeer

public void announcePeer(int index)

let all the connected peers know that this node finishes downloading a piece.

Parameters:

index - piece index

connectTo

public void connectTo(BTPeer p,
                      boolean chokedornot)

set up a connection to a peer

Parameters:

p - destination peer

chokedornot - initially choked or not

closeConnection

public void closeConnection(BTPeer p)

close connection to peer

Parameters:

p - destination peer

sendRequestTo

public void sendRequestTo(BTPeer p)

send a piece request message to a peer

Parameters:

p - destination peer

sendRequest

public void sendRequest(int index,
                        BTPeer p)

send request for a specific piece to a peer

Parameters:

index - piece index

p - destination peer

sendInterested

public void sendInterested(boolean interested,
                           BTPeer p)

send interested type peer message

Parameters:

interested - interested or uninterested

p - destination peer

sendChoked

public void sendChoked(boolean choked,
                       BTPeer p)

send choked type peer message

Parameters:

choked - choked or unchoked

p - destination peer

addNodeHasPiece

public boolean addNodeHasPiece(BTPeer node,
                               int piece)

update piece information in local database

Parameters:

node - peer

piece - piece index

Returns:

success or not

countPeersWithPiece

public int countPeersWithPiece(int i)

count peers with a specific piece

Parameters:

i - piece index

Returns:

count

toString

public java.lang.String toString()

gets string description

Overrides:

toString in class java.lang.Object

Returns:

a string describing this session