Package org.jgroups.protocols

Class TUNNEL

  • All Implemented Interfaces:
    AdditionalJmxObjects, DiagnosticsHandler.ProbeHandler, RouterStub.StubReceiver
    public class TUNNEL
extends TP
implements RouterStub.StubReceiver
    Replacement for UDP. Instead of sending packets via UDP, a TCP connection is opened to a Router (using the RouterStub client-side stub), the IP address/port of which was given using channel properties router_host and router_port. All outgoing traffic is sent via this TCP socket to the Router which distributes it to all connected TUNNELs in this group. Incoming traffic received from Router will simply be passed up the stack.

    A TUNNEL layer can be used to penetrate a firewall, most firewalls allow creating TCP connections to the outside world, however, they do not permit outside hosts to initiate a TCP connection to a host inside the firewall. Therefore, the connection created by the inside host is reused by Router to send traffic from an outside host to a host inside the firewall.

    Author:
    Bela Ban, Vladimir Blagojevic

    • Field Detail

      • reconnect_interval

        protected long reconnect_interval

      • tcp_nodelay

        protected boolean tcp_nodelay

      • use_nio

        protected boolean use_nio

      • gossip_router_hosts

        protected java.lang.String gossip_router_hosts

      • gossip_routers

        protected final java.util.List<java.net.InetSocketAddress> gossip_routers

      • sock

        protected java.net.DatagramSocket sock

    • Constructor Detail

      • TUNNEL

        public TUNNEL()

    • Method Detail

      • supportsMulticasting

        public boolean supportsMulticasting()
        We can simply send a message with dest == null and the GossipRouter will take care of routing it to all members in the cluster
        Specified by:
        supportsMulticasting in class TP

      • setGossipRouterHosts

        public void setGossipRouterHosts​(java.lang.String hosts)
                          throws java.net.UnknownHostException
        Throws:
        java.net.UnknownHostException

      • print

        public java.lang.String print()

      • printStubs

        public java.lang.String printStubs()

      • printReconnectList

        public java.lang.String printReconnectList()

      • toString

        public java.lang.String toString()
        Overrides:
        toString in class TP

      • getReconnectInterval

        public long getReconnectInterval()

      • setReconnectInterval

        public void setReconnectInterval​(long reconnect_interval)

      • init

        public void init()
          throws java.lang.Exception
        Description copied from class: Protocol
        Called after instance has been created (null constructor) and before protocol is started. Properties are already set. Other protocols are not yet connected and events cannot yet be sent.
        Overrides:
        init in class TP
        Throws:
        java.lang.Exception - Thrown if protocol cannot be initialized successfully. This will cause the ProtocolStack to fail, so the channel constructor will throw an exception

      • destroy

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

      • down

        public java.lang.Object down​(Event evt)
        Description copied from class: Protocol
        An event is to be sent down the stack. A protocol 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 protocol may need to add a header to it (or do nothing at all) before sending it down the stack using down_prot.down().
        Overrides:
        down in class TP

      • sendMulticast

        public void sendMulticast​(byte[] data,
                          int offset,
                          int length)
                   throws java.lang.Exception
        Description copied from class: TP
        Send to all members in the group. UDP would use an IP multicast message, whereas TCP would send N messages, one for each member
        Specified by:
        sendMulticast in class TP
        Parameters:
        data - The data to be sent. This is not a copy, so don't modify it
        Throws:
        java.lang.Exception

      • sendUnicast

        public void sendUnicast​(PhysicalAddress dest,
                        byte[] data,
                        int offset,
                        int length)
                 throws java.lang.Exception
        Description copied from class: TP
        Send a unicast to 1 member. Note that the destination address is a *physical*, not a logical address
        Specified by:
        sendUnicast in class TP
        Parameters:
        dest - Must be a non-null unicast address
        data - The data to be sent. This is not a copy, so don't modify it
        Throws:
        java.lang.Exception

      • sendToSingleMember

        protected void sendToSingleMember​(Address dest,
                                  byte[] buf,
                                  int offset,
                                  int length)
                           throws java.lang.Exception
        Overrides:
        sendToSingleMember in class TP
        Throws:
        java.lang.Exception

      • sendUnicast

        protected void sendUnicast​(Address dest,
                           byte[] data,
                           int offset,
                           int length)
                    throws java.lang.Exception
        Throws:
        java.lang.Exception

      • getInfo

        public java.lang.String getInfo()
        Specified by:
        getInfo in class TP