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Class JavaGroups.JavaStack.Protocols.FD

java.lang.Object
   |
   +----JavaGroups.JavaStack.Protocol
           |
           +----JavaGroups.JavaStack.Protocols.FD

public class FD
extends Protocol
implements Runnable
Failure detection based on simple heartbeat protocol. Regularly polls members for liveness. Passes SUSPECT message up the stack when a member is not reachable. The simple algorithms works as follows: the membership is known and ordered. Each HB protocol periodically sends a 'are-you-alive' message to its *neighbor*. A neighbor is the next in rank in the membership list. It is recomputed upon a view change. When a response hasn't been received for n milliseconds and m tries, the corresponding member is suspected (and eventually excluded if faulty).

FD starts when it detects (in a view change notification) that there are at least 2 members in the group. It stops running when the membership drops below 2.


Constructor Index

 o FD()

Method Index

 o Down(Event)
An event is to be sent down the stack.
 o GetName()
 o run()
 o SetProperties(Properties)
Configures the protocol initially.
 o Up(Event)
An event was received from the layer below.

Constructors

 o FD
 public FD()

Methods

 o GetName
 public String GetName()
Overrides:
GetName in class Protocol
 o SetProperties
 public boolean SetProperties(Properties props)
Configures the protocol initially.

Overrides:
SetProperties in class Protocol
 o Up
 public void Up(Event evt)
An event was received from the layer below.

Overrides:
Up in class Protocol
 o Down
 public void Down(Event evt)
An event is to be sent down the stack.

Overrides:
Down in class Protocol
 o run
 public void run()

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