TOA

java.lang.Object
- org.jgroups.stack.Protocol
- - org.jgroups.protocols.tom.TOA

All Implemented Interfaces:

DeliveryProtocol
```
public class TOA
extends Protocol
implements DeliveryProtocol
```
Total Order Anycast with three communication steps (based on Skeen's Algorithm). Establishes total order for a message sent to a subset of the cluster members (an anycast). Example: send a totally ordered message to {D,E} out of a membership of {A,B,C,D,E,F}.
Skeen's algorithm uses consensus among the anycast target members to find the currently highest sequence number (seqno) and delivers the message according to the order established by the seqnos.

Since:

3.1

Author:

Pedro Ruivo

Field Summary
- Fields inherited from class org.jgroups.stack.Protocol
  after_creation_hook, down_prot, ergonomics, id, log, name, stack, stats, up_prot

Constructor Summary

Constructors
Constructor and Description

TOA()

Constructors
Constructor and Description
`TOA()`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`deliver(Message message)` deliver a message
`java.lang.Object`	`down(Event evt)` An event is to be sent down the stack.
`void`	`enableStats(boolean flag)`
`double`	`getAvgDataMessageReceivedDuration()`
`double`	`getAvgFinalMessageReceivedDuration()`
`double`	`getAvgLastProposeMessageReceivedDuration()`
`double`	`getAvgNumberOfUnicastSentPerAnycast()`
`double`	`getAvgProposeMessageReceivedDuration()`
`double`	`getAvgToaSendDuration()`
`java.lang.String`	`getMessageList()`
`int`	`getNumberOfAnycastMessagesDelivered()`
`int`	`getNumberOfAnycastMessagesSent()`
`int`	`getNumberOfDataMessagesDelivered()`
`int`	`getNumberOfFinalAnycastSent()`
`int`	`getNumberOfFinalMessagesDelivered()`
`int`	`getNumberOfProposeMessageReceived()`
`int`	`getNumberOfProposeMessageSent()`
`void`	`resetStats()`
`void`	`start()` This method is called on a `Channel.connect(String)`.
`void`	`stop()` This method is called on a `Channel.disconnect()`.
`java.lang.Object`	`up(Event evt)` An event was received from the layer below.

Methods inherited from class org.jgroups.stack.Protocol
accept, afterCreationHook, destroy, dumpStats, getConfigurableObjects, getDownProtocol, getDownServices, getId, getIdsAbove, getLevel, getLog, getName, getProtocolStack, getSocketFactory, getThreadFactory, getTransport, getUpProtocol, getUpServices, getValue, init, isErgonomics, level, parse, printStats, providedDownServices, providedUpServices, requiredDownServices, requiredUpServices, resetStatistics, setDownProtocol, setErgonomics, setId, setLevel, setProtocolStack, setSocketFactory, setUpProtocol, setValue, setValues, statsEnabled, up

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - TOA
```
public TOA()
```
- Method Detail
  - start
```
public void start()
           throws java.lang.Exception
```
    Description copied from class: Protocol
    
    This method is called on a Channel.connect(String). Starts work. Protocols are connected and queues are ready to receive events. Will be called from bottom to top. This call will replace the START and START_OK events.
    
    Overrides:
    
    start in class Protocol
    
    Throws:
    
    java.lang.Exception - Thrown if protocol cannot be started successfully. This will cause the ProtocolStack to fail, so Channel.connect(String) will throw an exception
  - stop
```
public void stop()
```
    Description copied from class: Protocol
    
    This method is called on a Channel.disconnect(). Stops work (e.g. by closing multicast socket). Will be called from top to bottom. This means that at the time of the method invocation the neighbor protocol below is still working. This method will replace the STOP, STOP_OK, CLEANUP and CLEANUP_OK events. The ProtocolStack guarantees that when this method is called all messages in the down queue will have been flushed
    
    Overrides:
    
    stop in class Protocol
  - down
```
public java.lang.Object down(Event evt)
```
    Description copied from class: Protocol
    
    An event is to be sent down the stack. The layer may want to examine its type and perform some action on it, depending on the event's type. If the event is a message MSG, then the layer may need to add a header to it (or do nothing at all) before sending it down the stack using down_prot.down(). In case of a GET_ADDRESS event (which tries to retrieve the stack's address from one of the bottom layers), the layer may need to send a new response event back up the stack using up_prot.up().
    
    Overrides:
    
    down in class Protocol
  - up
```
public java.lang.Object up(Event evt)
```
    Description copied from class: Protocol
    
    An event was received from the layer below. Usually the current layer will want to examine the event type and - depending on its type - perform some computation (e.g. removing headers from a MSG event type, or updating the internal membership list when receiving a VIEW_CHANGE event). Finally the event is either a) discarded, or b) an event is sent down the stack using down_prot.down() or c) the event (or another event) is sent up the stack using up_prot.up().
    
    Overrides:
    
    up in class Protocol
  - deliver
```
public void deliver(Message message)
```
    Description copied from interface: DeliveryProtocol
    
    deliver a message
    
    Specified by:
    
    deliver in interface DeliveryProtocol
    
    Parameters:
    
    message - message to deliver
  - getMessageList
```
public java.lang.String getMessageList()
```
  - enableStats
```
public void enableStats(boolean flag)
```
    Overrides:
    
    enableStats in class Protocol
  - resetStats
```
public void resetStats()
```
    Overrides:
    
    resetStats in class Protocol
  - getAvgToaSendDuration
```
public double getAvgToaSendDuration()
```
  - getAvgDataMessageReceivedDuration
```
public double getAvgDataMessageReceivedDuration()
```
  - getAvgProposeMessageReceivedDuration
```
public double getAvgProposeMessageReceivedDuration()
```
  - getAvgLastProposeMessageReceivedDuration
```
public double getAvgLastProposeMessageReceivedDuration()
```
  - getAvgFinalMessageReceivedDuration
```
public double getAvgFinalMessageReceivedDuration()
```
  - getNumberOfAnycastMessagesSent
```
public int getNumberOfAnycastMessagesSent()
```
  - getNumberOfFinalAnycastSent
```
public int getNumberOfFinalAnycastSent()
```
  - getNumberOfAnycastMessagesDelivered
```
public int getNumberOfAnycastMessagesDelivered()
```
  - getNumberOfProposeMessageSent
```
public int getNumberOfProposeMessageSent()
```
  - getNumberOfFinalMessagesDelivered
```
public int getNumberOfFinalMessagesDelivered()
```
  - getNumberOfDataMessagesDelivered
```
public int getNumberOfDataMessagesDelivered()
```
  - getNumberOfProposeMessageReceived
```
public int getNumberOfProposeMessageReceived()
```
  - getAvgNumberOfUnicastSentPerAnycast
```
public double getAvgNumberOfUnicastSentPerAnycast()
```

Class TOA

Field Summary

Fields inherited from class org.jgroups.stack.Protocol

Constructor Summary

Method Summary

Methods inherited from class org.jgroups.stack.Protocol

Methods inherited from class java.lang.Object

Constructor Detail

TOA

Method Detail

start

stop

down

up

deliver

getMessageList

enableStats

resetStats

getAvgToaSendDuration

getAvgDataMessageReceivedDuration

getAvgProposeMessageReceivedDuration

getAvgLastProposeMessageReceivedDuration

getAvgFinalMessageReceivedDuration

getNumberOfAnycastMessagesSent

getNumberOfFinalAnycastSent

getNumberOfAnycastMessagesDelivered

getNumberOfProposeMessageSent

getNumberOfFinalMessagesDelivered

getNumberOfDataMessagesDelivered

getNumberOfProposeMessageReceived

getAvgNumberOfUnicastSentPerAnycast