Class OutboundConnectionCacheBlockingImpl<C extends Connection>

    • Constructor Detail

      • OutboundConnectionCacheBlockingImpl

        public OutboundConnectionCacheBlockingImpl​(java.lang.String cacheType,
                                                   int highWaterMark,
                                                   int numberToReclaim,
                                                   int maxParallelConnections,
                                                   long ttl)
    • Method Detail

      • internalCanCreateNewConnection

        private boolean internalCanCreateNewConnection​(OutboundCacheEntry<C> entry)
      • msg

        @InfoMethod
        private void msg​(java.lang.String m)
      • display

        @InfoMethod
        private void display​(java.lang.String m,
                             java.lang.Object value)
      • get

        public C get​(ContactInfo<C> cinfo,
                     ConnectionFinder<C> finder)
              throws java.io.IOException
        Description copied from interface: OutboundConnectionCache
        Return a Connection corresponding to the given ContactInfo. This works as follows:
        • Call the finder. If it returns non-null, use that connection; (Note that this may be a new connection, created in the finder). The finder SHOULD NOT create a new connection if canCreateNewConnection returns false, but this is advisory.
        • otherwise, Use an idle connection, if one is available;
        • otherwise, create a new connection, if not too many connections are open;
        • otherwise, use a busy connection.
        Note that creating a new connection requires EITHER:
        • there is no existing connection for the ContactInfo
        • OR the total number of connections in the cache is less than the HighWaterMark and the number of connections for this ContactInfo is less than MaxParallelConnections.
        We will always return a Connection for a get call UNLESS we have no existing connection and an attempt to create a new connection fails. In this case, the IOException thrown by ContactInfo.create is propagated out of this method.

        It is possible that the cache contains connections that no longer connect to their destination. In this case, it is the responsibility of the client of the cache to close the broken connection as they are detected. Connection reclamation may also handle the cleanup, but note that a broken connection with pending responses will never be reclaimed.

        Note that the idle and busy connection collections that are passed to the finder are unmodifiable collections. They have iterators that return connections in LRU order, with the least recently used connection first. This is done to aid a finder that wishes to consider load balancing in its determination of an appropriate connection.

        Specified by:
        get in interface OutboundConnectionCache<C extends Connection>
        Parameters:
        cinfo - info on Connection to get
        finder - Finder to use to search for Connection
        Returns:
        Connection corresponding to the ContactInfo
        Throws:
        java.io.IOException - if an error occurred
      • release

        public void release​(C conn,
                            int numResponsesExpected)
        Description copied from interface: OutboundConnectionCache
        Release a Connection previously obtained from get. Connections that have been released as many times as they have been returned by get are idle; otherwise a Connection is busy. Some number of responses (usually 0 or 1) may be expected ON THE SAME CONNECTION even for an idle connection. We maintain a count of the number of outstanding responses we expect for protocols that return the response on the same connection on which the request was received. This is necessary to prevent reclamation of a Connection that is idle, but still needed to send responses to old requests.
        Specified by:
        release in interface OutboundConnectionCache<C extends Connection>
        Parameters:
        conn - connection to release
        numResponsesExpected - number of responses expected
      • responseReceived

        public void responseReceived​(C conn)
        Decrement the number of expected responses. When a connection is idle and has no expected responses, it can be reclaimed.
        Specified by:
        responseReceived in interface OutboundConnectionCache<C extends Connection>
        Parameters:
        conn - Connection that has received a response
      • close

        public void close​(C conn)
        Close a connection, regardless of whether the connection is busy or not.
        Specified by:
        close in interface ConnectionCache<C extends Connection>
        Parameters:
        conn - connection to close
      • decrementTotalIdle

        private void decrementTotalIdle()
      • decrementTotalBusy

        private void decrementTotalBusy()