Class TCPGOSSIP


public class TCPGOSSIP extends Discovery
The TCPGOSSIP protocol layer retrieves the initial membership (used by the GMS when started by sending event FIND_INITIAL_MBRS down the stack). We do this by contacting one or more GossipRouters, which must be running at well-known addresses:ports. The responses should allow us to determine the coordinator whom we have to contact, e.g. in case we want to join the group. When we are a server (after having received the BECOME_SERVER event), we'll respond to TCPGOSSIP requests with a TCPGOSSIP response.

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

Author:
Bela Ban
  • Constructor Details

    • TCPGOSSIP

      public TCPGOSSIP()
  • Method Details

    • getName

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

      public boolean setProperties(Properties props)
      Description copied from class: Discovery
      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 class 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
    • 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
    • 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 Discovery
    • destroy

      public void destroy()
      Description copied from class: Protocol
      This method is called on a Channel.close(). Does some cleanup; after the call the VM will terminate
      Overrides:
      destroy in class Protocol
    • handleConnect

      public void handleConnect()
      Overrides:
      handleConnect in class Discovery
    • handleDisconnect

      public void handleDisconnect()
      Overrides:
      handleDisconnect in class Discovery
    • sendGetMembersRequest

      public void sendGetMembersRequest()
      Specified by:
      sendGetMembersRequest in class Discovery