Package org.jgroups.protocols

Class TCPPING

java.lang.Object

org.jgroups.stack.Protocol

org.jgroups.protocols.Discovery

org.jgroups.protocols.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 membership 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 configuration, 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

Nested Class Summary

Nested classes/interfaces inherited from class org.jgroups.protocols.Discovery

Discovery.Responses

Field Summary

Fields

Modifier and Type	Field	Description
protected final BoundedList<PhysicalAddress>	dynamic_hosts	https://jira.jboss.org/jira/browse/JGRP-989
protected int	max_dynamic_hosts

Fields inherited from class org.jgroups.protocols.Discovery

group_addr, local_addr, members, ping_responses, rank, timer, view

Fields inherited from class org.jgroups.stack.Protocol

down_prot, ergonomics, id, log, name, stack, stats, up_prot

Constructor Summary

Constructors

Constructor	Description
TCPPING()

Method Summary

Modifier and Type	Method	Description
void	discoveryRequestReceived(Address sender, String logical_name, Collection<PhysicalAddress> physical_addrs)
Object	down(Event evt)	An event is to be sent down the stack.
String	getDynamicHostList()
List<IpAddress>	getInitialHosts()	Returns the list of initial hosts as configured by the user via XML.
String	getInitialHostsList()
int	getPortRange()
void	init()	Called after instance has been created (null constructor) and before protocol is started.
void	sendGetMembersRequest(String cluster_name, Promise promise, boolean return_views_only)
void	setInitialHosts(List<IpAddress> initial_hosts)
void	setPortRange(int port_range)
void	start()	This method is called on a Channel.connect(String).

Methods inherited from class org.jgroups.protocols.Discovery

findAllMembers, findAllViews, findAllViewsAsString, findInitialMembers, findInitialMembers, findInitialMembersAsString, getNumberOfDiscoveryRequestsSent, getNumInitialMembers, getNumPingRequests, getTimeout, getView, handleConnect, handleDisconnect, makeView, providedUpServices, resetStats, setNumInitialMembers, setNumPingRequests, setTimeout, stop, up

Methods inherited from class org.jgroups.stack.Protocol

destroy, downThreadEnabled, dumpStats, enableStats, getConfigurableObjects, getDownProtocol, getId, getLevel, getName, getProperties, getProtocolStack, getSocketFactory, getThreadFactory, getTransport, getUpProtocol, getValue, isErgonomics, printStats, providedDownServices, requiredDownServices, requiredUpServices, setDownProtocol, setErgonomics, setId, setLevel, setProperties, setPropertiesInternal, setProperty, setProtocolStack, setSocketFactory, setUpProtocol, setValue, setValues, statsEnabled, upThreadEnabled

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

max_dynamic_hosts

protected int max_dynamic_hosts

dynamic_hosts

protected final BoundedList<PhysicalAddress> dynamic_hosts

https://jira.jboss.org/jira/browse/JGRP-989

Constructor Details

TCPPING

public TCPPING()

Method Details

getInitialHosts

public List<IpAddress> getInitialHosts()

Returns the list of initial hosts as configured by the user via XML. Note that the returned list is mutable, so careful with changes !

Returns:

List

list of initial hosts. This variable is only set after the channel has been created and set Properties() has been called

setInitialHosts

public void setInitialHosts(List<IpAddress> initial_hosts)

getPortRange

public int getPortRange()

setPortRange

public void setPortRange(int port_range)

getDynamicHostList

public String getDynamicHostList()

getInitialHostsList

public String getInitialHostsList()

init

public void init()
          throws 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 Discovery

Throws:

Exception - Thrown if protocol cannot be initialized successfully. This will cause the ProtocolStack to fail, so the channel constructor will throw an exception

start

public void start()
           throws 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 Discovery

Throws:

Exception - Thrown if protocol cannot be started successfully. This will cause the ProtocolStack to fail, so Channel.connect(String) will throw an exception

sendGetMembersRequest

public void sendGetMembersRequest(String cluster_name,
 Promise promise,
 boolean return_views_only)
                           throws Exception

Specified by:

sendGetMembersRequest in class Discovery

Throws:

Exception

down

public Object down(Event evt)

Description copied from class: Discovery

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 up_prot.up(). The PING protocol is interested in several different down events, Event.FIND_INITIAL_MBRS - sent by the GMS layer and expecting a GET_MBRS_OK Event.TMP_VIEW and Event.VIEW_CHANGE - a view change event Event.BECOME_SERVER - called after client has joined and is fully working group member Event.CONNECT, Event.DISCONNECT.

Overrides:

down in class Discovery

discoveryRequestReceived

public void discoveryRequestReceived(Address sender,
 String logical_name,
 Collection<PhysicalAddress> physical_addrs)

Overrides:

discoveryRequestReceived in class Discovery