net.sf.appia.protocols.total.sequencer
Class Buffer

java.lang.Object
  net.sf.appia.protocols.total.sequencer.Buffer

public class Buffer
extends java.lang.Object

Class that implements a buffer to store events while waiting for the total order.

Constructor Summary

Buffer()
Constructs a new Buffer object.

Method Summary

InfoMessage	find(int emissor, int seq) Finds and returns if available a InfoMessage object.
GroupSendableEvent	getMinimum() Returns an event from the buffer in a deterministic way.
GroupSendableEvent	getReadyEvent(int ordem) Gives an event ready to be delivered
void	insert(int o, int e, int seq, GroupSendableEvent ev) Insert a new InfoMessage
void	insertEvent(int emissor, int seq, GroupSendableEvent ev) Insert a new event
void	insertOrder(int o, int emissor, int seq) Insert a new order
boolean	isEmpty()
int	size()

Methods inherited from class java.lang.Object

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

Constructor Detail

Buffer

public Buffer()

Constructs a new Buffer object.

Method Detail

insert

public void insert(int o,
                   int e,
                   int seq,
                   GroupSendableEvent ev)

Insert a new InfoMessage

Parameters:

o - total order of the message

e - sender of the message

seq - individual sequence number

ev - the event to be stored

find

public InfoMessage find(int emissor,
                        int seq)

Finds and returns if available a InfoMessage object.

Parameters:

emissor - sender of the message that wanted

seq - sequence number of the message wanted

insertOrder

public void insertOrder(int o,
                        int emissor,
                        int seq)

Insert a new order

Parameters:

o - the order to be given to the message

emissor - the sender of the message to be ordered

seq - the individual sequence number of the message to be ordered

insertEvent

public void insertEvent(int emissor,
                        int seq,
                        GroupSendableEvent ev)

Insert a new event

Parameters:

emissor - the sender of the message to be ordered

seq - the individual sequence number of the message to be ordered

ev - the event to be ordered

getReadyEvent

public GroupSendableEvent getReadyEvent(int ordem)

Gives an event ready to be delivered

Returns:

The event to be delivered or null if none is available

isEmpty

public boolean isEmpty()

Returns:

true if the buffer is empty and false otherwise

size

public int size()

getMinimum

public GroupSendableEvent getMinimum()

Returns an event from the buffer in a deterministic way. Used when there are view changes in the group

Returns:

The event