org.javagroups.protocols
Class UNIFORM

org.javagroups.protocols.UNIFORM

public class UNIFORM

The algorithms implements dynamically-uniform failure-atomic group multicast, that is, a message is delivered by all members if it is delivered by at least 1 non-faulty member even if the sender crashes after sending. If the sender crashes, it will eventually be removed from the group membership: the FLUSH protocol preceding the view change causes all pending multicasts to be flushed out of the system, thereby re-sending pending multicasts to members that haven't received them yet.

The protocol makes use of GroupRequest (which itself uses RequestCorrelator) to send a request to all members and receive responses from all non-faulty members.


Constructor Summary
UNIFORM()
           
 
Method Summary
 void down(org.javagroups.protocols.Event evt)
           
 java.lang.String getName()
           
 java.lang.Object handle(org.javagroups.protocols.Message msg)
           1.
 java.lang.Object receive(long timeout)
           
 void reset()
          Just remove if you don't need to reset any state
 void send(org.javagroups.protocols.Message msg)
           
 boolean setProperties(java.util.Properties props)
           
 void up(org.javagroups.protocols.Event evt)
           
 

Constructor Detail

UNIFORM

public UNIFORM()
Method Detail

getName

public java.lang.String getName()

setProperties

public boolean setProperties(java.util.Properties props)

reset

public void reset()
Just remove if you don't need to reset any state

up

public void up(org.javagroups.protocols.Event evt)

down

public void down(org.javagroups.protocols.Event evt)

handle

public java.lang.Object handle(org.javagroups.protocols.Message msg)
1. Remove UniformHeader from message and get ID and type
2. If type == SAVE: add message to save-table (key=sender + ID) and send response (SAVE_OK)
If type == OK:   add message to ok-table, remove from save-table. Deliver message (pass up
the stack) and send response (OK_OK).
If type == SEEN: find message in ok-table. If found, send SEEN_OK response, else NOT_SEEN.
If type == GC: delete message from ok-table.

send

public void send(org.javagroups.protocols.Message msg)
          throws java.lang.Exception

receive

public java.lang.Object receive(long timeout)
                         throws java.lang.Exception


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