Package org.jgroups.demos

Class QuoteServer

  • All Implemented Interfaces:
    MembershipListener, MessageListener
    public class QuoteServer
extends java.lang.Object
implements MembershipListener, MessageListener
    Example of a replicated quote server. The server maintains state which consists of a list of quotes and their corresponding values. When it is started, it tries to reach other quote servers to get its initial state. If it does not receive any response after 5 seconds, it assumes it is the first server and starts processing requests.

    Any updates are multicast across the cluster

    Author:
    Bela Ban

    • Constructor Summary

      Constructors 
      Constructor Description
      QuoteServer()  

    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      void block()
      Called (usually by the FLUSH protocol), as an indication that the member should stop sending messages.
      java.util.Hashtable getAllStocks()  
      float getQuote​(java.lang.String stock_name)  
      byte[] getState()
      Answers the group state; e.g., when joining.
      static void main​(java.lang.String[] args)  
      void printAllStocks()  
      void receive​(Message msg)
      Called when a message is received.
      void setQuote​(java.lang.String stock_name, java.lang.Float value)  
      void setState​(byte[] state)
      Sets the group state; e.g., when joining.
      void start()  
      void suspect​(Address suspected_mbr)
      Called whenever a member is suspected of having crashed, but has not yet been excluded.
      void viewAccepted​(View new_view)
      Called when a change in membership has occurred.

      • Methods inherited from class java.lang.Object

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

    • Constructor Detail

      • QuoteServer

        public QuoteServer()

    • Method Detail

      • viewAccepted

        public void viewAccepted​(View new_view)
        Description copied from interface: MembershipListener
        Called when a change in membership has occurred. No long running actions or sending of messages should be done in this callback. If some long running action needs to be performed, it should be done in a separate thread.

        Note that on reception of the first view (a new member just joined), the channel will not yet be in the connected state. This only happens when Channel.connect(String) returns.

        Specified by:
        viewAccepted in interface MembershipListener

      • suspect

        public void suspect​(Address suspected_mbr)
        Description copied from interface: MembershipListener
        Called whenever a member is suspected of having crashed, but has not yet been excluded.
        Specified by:
        suspect in interface MembershipListener

      • block

        public void block()
        Description copied from interface: MembershipListener
        Called (usually by the FLUSH protocol), as an indication that the member should stop sending messages. Any messages sent after returning from this callback might get blocked by the FLUSH protocol. When the FLUSH protocol is done, and messages can be sent again, the FLUSH protocol will simply unblock all pending messages. If a callback for unblocking is desired, implement ExtendedMembershipListener.unblock(). Note that block() is the equivalent of reception of a BlockEvent in the pull mode.
        Specified by:
        block in interface MembershipListener

      • start

        public void start()

      • getQuote

        public float getQuote​(java.lang.String stock_name)
               throws java.lang.Exception
        Throws:
        java.lang.Exception

      • setQuote

        public void setQuote​(java.lang.String stock_name,
                     java.lang.Float value)

      • getAllStocks

        public java.util.Hashtable getAllStocks()

      • printAllStocks

        public void printAllStocks()

      • getState

        public byte[] getState()
        Description copied from interface: MessageListener
        Answers the group state; e.g., when joining.
        Specified by:
        getState in interface MessageListener
        Returns:
        byte[]

      • setState

        public void setState​(byte[] state)
        Description copied from interface: MessageListener
        Sets the group state; e.g., when joining.
        Specified by:
        setState in interface MessageListener

      • main

        public static void main​(java.lang.String[] args)