Class MPING

java.lang.Object
org.jgroups.stack.Protocol
org.jgroups.protocols.Discovery
org.jgroups.protocols.PING
org.jgroups.protocols.MPING
All Implemented Interfaces:
Runnable
public class MPING extends PING implements Runnable
Uses its own IP multicast socket to send and receive discovery requests/responses. Can be used in conjuntion with a non-UDP transport, e.g. TCP.

The discovery is assymetric: discovery requests are broadcast via the multicast socket, and received via the multicast socket by everyone in the group. However, the discovery responses are sent back via the regular transport (e.g. TCP) to the sender (discovery request contained sender's regular address, e.g. 192.168.0.2:7800).

Version:
$Id: MPING.java,v 1.29.2.7 2009/02/05 08:17:36 belaban Exp $
Author:
Bela Ban

  • Constructor Details

    • MPING

      public MPING()

  • Method Details

    • getName

      public String getName()
      Overrides:
      getName in class PING

    • getBindAddr

      public InetAddress getBindAddr()

    • setBindAddr

      public void setBindAddr(InetAddress bind_addr)

    • getReceiveInterfaces

      public List<NetworkInterface> getReceiveInterfaces()

    • getSendInterfaces

      public List<NetworkInterface> getSendInterfaces()

    • isReceiveOnAllInterfaces

      public boolean isReceiveOnAllInterfaces()

    • isSendOnAllInterfaces

      public boolean isSendOnAllInterfaces()

    • getTTL

      public int getTTL()

    • setTTL

      public void setTTL(int ip_ttl)

    • getMcastAddr

      public InetAddress getMcastAddr()

    • setMcastAddr

      public void setMcastAddr(InetAddress mcast_addr)

    • getMcastPort

      public int getMcastPort()

    • setMcastPort

      public void setMcastPort(int mcast_port)

    • setProperties

      public boolean setProperties(Properties props)
      Description copied from class: PING
      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 property: gossip_host - if you are using GOSSIP then this defines the host of the GossipRouter, default is null property: gossip_port - if you are using GOSSIP then this defines the port of the GossipRouter, default is null
      Overrides:
      setProperties in class PING
      Parameters:
      props - - a property set containing only PING properties
      Returns:
      returns true if all properties were parsed properly returns false if there are unrecnogized properties in the property set

    • up

      public Object up(Event evt)
      Description copied from class: Discovery
      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.

      For the PING protocol, the Up operation does the following things. 1. If the event is a Event.MSG then PING will inspect the message header. If the header is null, PING simply passes up the event If the header is PingHeader.GET_MBRS_REQ then the PING protocol will PassDown a PingRequest message If the header is PingHeader.GET_MBRS_RSP we will add the message to the initial members vector and wake up any waiting threads. 2. If the event is Event.SET_LOCAL_ADDR we will simple set the local address of this protocol 3. For all other messages we simple pass it up to the protocol above

      Overrides:
      up in class PING
      Parameters:
      evt - - the event that has been sent from the layer below

    • 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 PING

    • run

      public void run()
      Specified by:
      run in interface Runnable