Class VIEW_SYNC

java.lang.Object
org.jgroups.stack.Protocol
org.jgroups.protocols.VIEW_SYNC

public class VIEW_SYNC extends Protocol
Periodically sends the view to the group. When a view is received which is greater than the current view, we install it. Otherwise we simply discard it. This is used to solve the problem for unreliable view dissemination outlined in JGroups/doc/ReliableViewInstallation.txt. This protocol is supposed to be just below GMS.
Version:
$Id: VIEW_SYNC.java,v 1.24.2.2 2008/05/22 13:23:06 belaban Exp $
Author:
Bela Ban
  • Constructor Details

    • VIEW_SYNC

      public VIEW_SYNC()
  • Method Details

    • getName

      public String getName()
      Specified by:
      getName in class Protocol
    • getAverageSendInterval

      public long getAverageSendInterval()
    • setAverageSendInterval

      public void setAverageSendInterval(long gossip_interval)
    • getNumViewsSent

      public int getNumViewsSent()
    • getNumViewRequestsSent

      public int getNumViewRequestsSent()
    • getNumViewResponsesSeen

      public int getNumViewResponsesSeen()
    • getNumViewsNonLocal

      public int getNumViewsNonLocal()
    • getNumViewsLess

      public int getNumViewsLess()
    • getNumViewsEqual

      public int getNumViewsEqual()
    • getLastViewRequestSent

      public long getLastViewRequestSent()
    • getNumViewsAdjusted

      public int getNumViewsAdjusted()
    • resetStats

      public void resetStats()
      Overrides:
      resetStats in class Protocol
    • setProperties

      public boolean setProperties(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
    • 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 Protocol
      Throws:
      Exception - Thrown if protocol cannot be started successfully. This will cause the ProtocolStack to fail, so Channel.connect(String) 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
    • sendViewRequest

      public void sendViewRequest()
      Sends a VIEW_SYNC_REQ to all members, every member replies with a VIEW multicast
    • up

      public 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 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