org.jgroups.protocols

Class TCPPING


public class TCPPING
extends Discovery

The TCPPING protocol layer retrieves the initial membership in answer to the GMS's FIND_INITIAL_MBRS event. The initial membership is retrieved by directly contacting other group members, sending point-to-point mebership requests. The responses should allow us to determine the coordinator whom we have to contact in case we want to join the group. When we are a server (after having received the BECOME_SERVER event), we'll respond to TCPPING requests with a TCPPING response.

The FIND_INITIAL_MBRS event will eventually be answered with a FIND_INITIAL_MBRS_OK event up the stack.

The TCPPING protocol requires a static conifiguration, which assumes that you to know in advance where to find other members of your group. For dynamic discovery, use the PING protocol, which uses multicast discovery, or the TCPGOSSIP protocol, which contacts a Gossip Router to acquire the initial membership.

Author:
Bela Ban

Field Summary

Fields inherited from class org.jgroups.stack.Protocol

down_handler, down_prot, down_queue, down_thread, down_thread_prio, log, observer, props, stack, stats, trace, up_handler, up_prot, up_queue, up_thread, up_thread_prio, warn

Method Summary

String
getName()
void
localAddressSet(Address addr)
Called after local_addr was set
void
sendGetMembersRequest()
boolean
setProperties(Properties props)
sets the properties of the PING protocol.

Methods inherited from class org.jgroups.protocols.Discovery

down, findInitialMembers, findInitialMembersAsString, getNumInitialMembers, getNumPingRequests, getNumberOfDiscoveryRequestsSent, getTimeout, handleConnect, handleConnectOK, handleDisconnect, localAddressSet, makeView, providedUpServices, resetStats, sendGetMembersRequest, setNumInitialMembers, setNumPingRequests, setProperties, setTimeout, start, stop, up

Methods inherited from class org.jgroups.stack.Protocol

destroy, down, downThreadEnabled, dumpStats, enableStats, getDownProtocol, getDownQueue, getName, getProperties, getUpProtocol, getUpQueue, handleSpecialDownEvent, init, isTrace, isWarn, passDown, passUp, printStats, providedDownServices, providedUpServices, receiveDownEvent, receiveUpEvent, requiredDownServices, requiredUpServices, resetStats, setDownProtocol, setObserver, setProperties, setPropertiesInternal, setProtocolStack, setTrace, setUpProtocol, setWarn, start, startDownHandler, startUpHandler, statsEnabled, stop, stopInternal, up, upThreadEnabled

Method Details

getName

public String getName()
Overrides:
getName in interface Protocol

localAddressSet

public void localAddressSet(Address addr)
Called after local_addr was set
Overrides:
localAddressSet in interface Discovery

sendGetMembersRequest

public void sendGetMembersRequest()
Overrides:
sendGetMembersRequest in interface Discovery

setProperties

public boolean setProperties(Properties props)
sets the properties of the PING protocol. The following properties are available property: timeout - the timeout (ms) to wait for the initial members, default is 3000=3 secs property: num_initial_members - the minimum number of initial members for a FIND_INITAL_MBRS, default is 2
Overrides:
setProperties in interface Discovery
Parameters:
props - - a property set
Returns:
returns true if all properties were parsed properly returns false if there are unrecnogized properties in the property set

Copyright B) 1998-2005 Bela Ban. All Rights Reserved.