org.jgroups.protocols
Class FD_ALL

java.lang.Object
  extended by org.jgroups.stack.Protocol
      extended by org.jgroups.protocols.FD_ALL

public class FD_ALL
extends Protocol

Failure detection based on simple heartbeat protocol. Every member periodically multicasts a heartbeat. Every member also maintains a table of all members (minus itself). When data or a heartbeat from P are received, we reset the timestamp for P to the current time. Periodically, we check for expired members, and suspect those.

Version:
$Id: FD_ALL.java,v 1.12.2.3 2008/06/18 17:34:57 vlada Exp $
Author:
Bela Ban

Nested Class Summary
static class FD_ALL.Header
           
 
Field Summary
protected  int num_heartbeats_received
           
protected  int num_heartbeats_sent
           
protected  int num_suspect_events
           
 
Fields inherited from class org.jgroups.stack.Protocol
down_prot, log, props, stack, stats, up_prot
 
Constructor Summary
FD_ALL()
           
 
Method Summary
 java.lang.Object down(Event evt)
          An event is to be sent down the stack.
 int getHeartbeatsReceived()
           
 int getHeartbeatsSent()
           
 long getInterval()
           
 java.lang.String getLocalAddress()
           
 java.lang.String getMembers()
           
 java.lang.String getName()
           
 int getSuspectEventsSent()
           
 long getTimeout()
           
 void init()
          Called after instance has been created (null constructor) and before protocol is started.
 boolean isRunning()
           
 boolean isShun()
           
 java.lang.String printSuspectHistory()
           
 java.lang.String printTimestamps()
           
 void resetStats()
           
 void setInterval(long interval)
           
 boolean setProperties(java.util.Properties props)
          Configures the protocol initially.
 void setShun(boolean flag)
           
 void setTimeout(long timeout)
           
 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
destroy, downThreadEnabled, dumpStats, enableStats, getDownProtocol, getProperties, getProtocolStack, getThreadFactory, getTransport, getUpProtocol, printStats, providedDownServices, providedUpServices, requiredDownServices, requiredUpServices, setDownProtocol, setPropertiesInternal, setProtocolStack, setUpProtocol, start, statsEnabled, upThreadEnabled
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

num_heartbeats_sent

protected int num_heartbeats_sent

num_heartbeats_received

protected int num_heartbeats_received

num_suspect_events

protected int num_suspect_events
Constructor Detail

FD_ALL

public FD_ALL()
Method Detail

getName

public java.lang.String getName()
Specified by:
getName in class Protocol

getLocalAddress

public java.lang.String getLocalAddress()

getMembers

public java.lang.String getMembers()

getHeartbeatsSent

public int getHeartbeatsSent()

getHeartbeatsReceived

public int getHeartbeatsReceived()

getSuspectEventsSent

public int getSuspectEventsSent()

getTimeout

public long getTimeout()

setTimeout

public void setTimeout(long timeout)

getInterval

public long getInterval()

setInterval

public void setInterval(long interval)

isShun

public boolean isShun()

setShun

public void setShun(boolean flag)

isRunning

public boolean isRunning()

printSuspectHistory

public java.lang.String printSuspectHistory()

printTimestamps

public java.lang.String printTimestamps()

setProperties

public boolean setProperties(java.util.Properties props)
Description copied from class: Protocol
Configures the protocol initially. A configuration string consists of name=value items, separated by a ';' (semicolon), e.g.:
 "loopback=false;unicast_inport=4444"
 

Overrides:
setProperties in class Protocol

resetStats

public void resetStats()
Overrides:
resetStats in class Protocol

init

public void init()
          throws java.lang.Exception
Description copied from class: Protocol
Called after instance has been created (null constructor) and before protocol is started. Properties are already set. Other protocols are not yet connected and events cannot yet be sent.

Overrides:
init in class Protocol
Throws:
java.lang.Exception - Thrown if protocol cannot be initialized successfully. This will cause the ProtocolStack to fail, so the channel constructor 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

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

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


Copyright © 1998-2008 Bela Ban. All Rights Reserved.