org.jgroups.protocols.pbcast
Class FD
java.lang.Object
org.jgroups.stack.Protocol
org.jgroups.protocols.pbcast.FD
- All Implemented Interfaces:
- java.lang.Runnable
public class FD
- extends Protocol
- implements java.lang.Runnable
Passive failure detection protocol. It assumes a pbcast protocol, which uses rounds of gossiping for
reliable message delivery. Gossip protocols typically involve all the members sending gossips in regular
intervals. This protocol therefore works as follows: it allocates a timestamp for each member and updates
the timestamp whenever it receives a message from a sender P. Any type of message is accepted from P. For
example, PBCAST regularly sends the following messages:
- regular mcast message from P
- regular ucast message from P
- gossip from P
- retransmit request from P
- retransmit response from P
- Author:
- Bela Ban
Fields inherited from class org.jgroups.stack.Protocol |
down_handler, down_prot, down_queue, down_thread, down_thread_prio, log, observer, props, stack, stats, up_handler, up_prot, up_queue, up_thread, up_thread_prio |
Method Summary |
void |
down(Event evt)
An event is to be sent down the stack. |
java.lang.String |
getName()
|
void |
run()
|
boolean |
setProperties(java.util.Properties props)
Configures the protocol initially. |
void |
stop()
This method is called on a Channel.disconnect() . |
void |
up(Event evt)
An event was received from the layer below. |
Methods inherited from class org.jgroups.stack.Protocol |
destroy, downThreadEnabled, dumpStats, enableStats, getDownProtocol, getDownQueue, getProperties, getUpProtocol, getUpQueue, handleSpecialDownEvent, init, passDown, passUp, printStats, providedDownServices, providedUpServices, receiveDownEvent, receiveUpEvent, requiredDownServices, requiredUpServices, resetStats, setDownProtocol, setObserver, setPropertiesInternal, setProtocolStack, setUpProtocol, start, startDownHandler, startUpHandler, statsEnabled, stopInternal, upThreadEnabled |
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
FD
public FD()
getName
public java.lang.String getName()
- Specified by:
getName
in class Protocol
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
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 void 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
passDown()
or c) the event (or another event) is sent up
the stack using passUp()
.
- Overrides:
up
in class Protocol
down
public void 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
passDown()
. 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 passUp()
.
- Overrides:
down
in class Protocol
run
public void run()
- Specified by:
run
in interface java.lang.Runnable
Copyright ? 1998-2006 Bela Ban. All Rights Reserved.