Class LocalVNS

  • All Implemented Interfaces:
    java.lang.Runnable, TransportableFactory, VinciServable

    public class LocalVNS
    extends VinciServableAdapter
    implements java.lang.Runnable
    LOCAL Vinci Naming Service. Used by locally deployed TAEs. Locally, meaning TAEs running on the same machine but in different JVM. This VNS is primarily used by TAEs to advertise their availability after succesfull startup.
    • Constructor Summary

      Constructors 
      Constructor Description
      LocalVNS()  
      LocalVNS​(int aStartPort, int aEndPort, int aVNSPort)
      Initialize local VNS instance with a range of ports, and the port for the VNS itself.
      LocalVNS​(java.lang.String aStartPort, java.lang.String aEndPort, java.lang.String aVNSPort)
      Instantiates Local Vinci Naming Service
    • Constructor Detail

      • LocalVNS

        public LocalVNS()
      • LocalVNS

        public LocalVNS​(java.lang.String aStartPort,
                        java.lang.String aEndPort,
                        java.lang.String aVNSPort)
                 throws java.net.PortUnreachableException
        Instantiates Local Vinci Naming Service
        Parameters:
        aStartPort - - a starting port # for clients (services)
        aEndPort - - an ending port # for clients( services)
        aVNSPort - - port on which this VNS will listen on
        Throws:
        java.net.PortUnreachableException
      • LocalVNS

        public LocalVNS​(int aStartPort,
                        int aEndPort,
                        int aVNSPort)
                 throws java.net.PortUnreachableException
        Initialize local VNS instance with a range of ports, and the port for the VNS itself. A given port is tested first for availability. If it is not available the next port is tested, until one is found to be available.
        Parameters:
        aStartPort - - starting port number used
        aEndPort - - end port number. Together with StartPort defines the range of ports (port pool)
        aVNSPort - - port on which this VNS will listen for requests
        Throws:
        java.net.PortUnreachableException - unreachable port after retries
    • Method Detail

      • setConnectionPool

        public void setConnectionPool​(BoundedWorkQueue pQueue)
        Associates a port pool with instance of VNS.
        Parameters:
        pQueue - - queue where allocated ports will be added
      • isAvailable

        public boolean isAvailable​(int port)
        Determines if a given port is free. It establishes a short lived connection to the port and if successful returns false.
        Parameters:
        port - number to check
      • getVNSPort

        public int getVNSPort()
        Returns the port number on which local VNS is listening for requests.
        Returns:
        - VNS port number
      • getPort

        public int getPort()
                    throws java.net.PortUnreachableException
        Returns the next available port. The port is allocated from a cache of ports given to the VNS service on startup.
        Returns:
        - free port
        Throws:
        java.net.PortUnreachableException - can't get port in configured range
      • eval

        public Transportable eval​(Transportable in)
                           throws ServiceException
        Main method called by services advertising their availability. Each service, on startup sends "serveon" request to VNS and waits for assigned port. The VNS looks up its cahce of ports and returns to the service one that has not yest allocated.
        Specified by:
        eval in interface VinciServable
        Specified by:
        eval in class VinciServableAdapter
        Parameters:
        in - The input document
        Returns:
        The output document
        Throws:
        ServiceException - thrown when there is an application level error that should result in the client receiving the same ServiceException on the other end.
      • shutdown

        public void shutdown()
        Stop the VNS service
      • finalize

        protected void finalize()
                         throws java.lang.Throwable
        Overrides:
        finalize in class java.lang.Object
        Throws:
        java.lang.Throwable
      • run

        public void run()
        Starts VNS thread. This thread runs continuously waiting for service registrations and returning port number back.
        Specified by:
        run in interface java.lang.Runnable