}

        byte[] mac = PacMac.calculateMacArcfourHMACMD5(usage, makeKey(keybytes, 23), bytes);
        checkBytes(javaChecksum, mac);
        checkBytes(Hex.decode(expect), mac);
    }


    /**
     * @param keybytes
     * @return
     */
    private static KerberosKey makeKey ( byte[] keybytes, int etype ) {
        return new KerberosKey(null, keybytes, etype, 0);
    }

     */
    int state = 0;

    String name = "Transport" + id++;
    Thread thread;
    TransportException te;

    protected HashMap response_map = new HashMap( 4 );

    protected abstract void makeKey( Request request ) throws IOException;
    protected abstract Request peekKey() throws IOException;
    protected abstract void doSend( Request request ) throws IOException;

    }


    /**
     * @return the number of known usages
     */
    protected long getUsageCount () {
        return this.usageCount.get();
    }


    protected abstract long makeKey ( Request request ) throws IOException;


    protected abstract Long peekKey () throws IOException;


    protected abstract void doSend ( Request request ) throws IOException;

            in.close();
            socket.close();
        } finally {
            digest = null;
            socket = null;
            tconHostName = null;
        }
    }

    protected void makeKey( Request request ) throws IOException {
        /* The request *is* the key */
        if (++mid == 32000) mid = 1;
        ((ServerMessageBlock)request).mid = mid;
    }

    /**
     * @return
     * @throws IOException
     */
    private int negotiateWrite ( CommonServerMessageBlockRequest req, boolean setmid ) throws IOException {
        if ( setmid ) {
            makeKey(req);
        }
        else {
            req.setMid(0);
            this.mid.set(1);
        }
        int n = req.encode(this.sbuf, 4);