ec.exchange

Class IslandExchangeMailbox

java.lang.Object

ec.exchange.IslandExchangeMailbox

All Implemented Interfaces:

Runnable

class IslandExchangeMailbox
extends Object
implements Runnable

Class that contains all the mailbox functionality. It is supposed to wait on a new thread for incoming immigrants from other islands (it will receive in the constructor the number of islands that will send messages to the current island). Waiting on sockets is non-blocking, such that the order in which the islands send messages is unimportant. When immigrants are received, they are stored in a special buffer called immigrants. The storage is managed in a queue-like fashion, such that when the storage is full, the first immigrants that came are erased (hopefully the storage will be emptied fast enough such that this case doesn't appear too often). All accesses to the "immigrants" variable (also applies to nImmigrants) should be done only in the presence of synchronization, because there might be other threads using them too. The number of immigrants for each of the subpopulations (nImmigrants[x]) is between 0 and the size of the queue structure (received as a parameter in the constructor).

Field Summary

Fields

Modifier and Type	Field and Description
(package private) boolean	chatty
static int	CHECK_TIMEOUT How much to wait on a socket for a message, before starting to wait on another socket
(package private) boolean	compressedCommunication
(package private) DataInputStream[]	dataInput
Individual[][]	immigrants storage for the incoming immigrants: 2 sizes: the subpopulation and the index of the immigrant
String[]	incomingIds
(package private) Socket[]	inSockets
(package private) String	myId
(package private) int	n_incoming
(package private) int[]	nextIndexPosition
int[]	nImmigrants the number of immigrants in the storage for each of the subpopulations
(package private) boolean[]	running
(package private) ServerSocket	serverSocket
static int	SLEEP_BETWEEN_CHECKING_FOR_IMMIGRANTS How much to wait before starting checking for immigrants
(package private) EvolutionState	state
static int	SYNCHRONIZATION_SLEEP How much to wait while synchronizing
(package private) boolean[]	syncVar

Constructor Summary

Constructors

Constructor and Description

IslandExchangeMailbox(EvolutionState state_p, int port, int n_incoming_p, int how_many, String _myId, boolean chatty, boolean _compressedCommunication) Public constructor used to initialize most of the parameters of the mailbox: state_p : the EvolutionState, used mainly for displaying messages port : the port used to listen for incoming messages n_incoming_p : the number of islands that will send messages to the current island how_many : how many immigrants to manage in the queue-like storage for each of the subpopulations

Method Summary

Modifier and Type	Method and Description
int	getPort() Return the port of the ServerSocket (where the islands where the other islands should connect in order to send their immigrants).
void	run() The main functionality of the mailbox: waiting for incoming messages and dealing with the incoming immigrants
void	shutDown() Method used to shutdown the mailbox.

Methods inherited from class java.lang.Object

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

Field Detail

SLEEP_BETWEEN_CHECKING_FOR_IMMIGRANTS

public static final int SLEEP_BETWEEN_CHECKING_FOR_IMMIGRANTS

How much to wait before starting checking for immigrants

See Also:

Constant Field Values

CHECK_TIMEOUT

public static final int CHECK_TIMEOUT

How much to wait on a socket for a message, before starting to wait on another socket

See Also:

Constant Field Values

SYNCHRONIZATION_SLEEP

public static final int SYNCHRONIZATION_SLEEP

How much to wait while synchronizing

See Also:

Constant Field Values

immigrants

public Individual[][] immigrants

storage for the incoming immigrants: 2 sizes: the subpopulation and the index of the immigrant

nImmigrants

public int[] nImmigrants

the number of immigrants in the storage for each of the subpopulations

nextIndexPosition

int[] nextIndexPosition

serverSocket

ServerSocket serverSocket

n_incoming

int n_incoming

compressedCommunication

boolean compressedCommunication

inSockets

Socket[] inSockets

dataInput

DataInputStream[] dataInput

incomingIds

public String[] incomingIds

running

boolean[] running

state

EvolutionState state

syncVar

boolean[] syncVar

myId

String myId

chatty

boolean chatty

Constructor Detail

IslandExchangeMailbox

public IslandExchangeMailbox(EvolutionState state_p,
                             int port,
                             int n_incoming_p,
                             int how_many,
                             String _myId,
                             boolean chatty,
                             boolean _compressedCommunication)

Public constructor used to initialize most of the parameters of the mailbox: state_p : the EvolutionState, used mainly for displaying messages port : the port used to listen for incoming messages n_incoming_p : the number of islands that will send messages to the current island how_many : how many immigrants to manage in the queue-like storage for each of the subpopulations

Method Detail

run

public void run()

The main functionality of the mailbox: waiting for incoming messages and dealing with the incoming immigrants

Specified by:

run in interface Runnable

shutDown

public void shutDown()

Method used to shutdown the mailbox. What it does is that it closes all communication links (sockets) and sets the syncVar to true (such that if the run() method is run on another thread, it will exit the loop and terminate.

getPort

public int getPort()

Return the port of the ServerSocket (where the islands where the other islands should connect in order to send their immigrants).