Tomcat4 默认连接器

删了很多，只留下了主要脉络，以便回忆TOMCAT如何做到多线程处理请求

    /**
     * The set of processors that have been created but are not currently
     * being used to process a request.
     */
    private Stack processors = new Stack();
    
    /**
     * The set of processors that have ever been created.
     */
    private Vector created = new Vector();


    /**
     * The current number of processors that have been created.
     */
    private int curProcessors = 0;

 /**
     * Create (or allocate) and return an available processor for use in
     * processing a specific HTTP request, if possible.  If the maximum
     * allowed processors have already been created and are in use,  
     * returnnull instead.
     **/
    private HttpProcessor createProcessor() {

        synchronized (processors) {
            if (processors.size() > 0) {
                // if (debug >= 2)
                // log("createProcessor: Reusing existing processor");
                return ((HttpProcessor) processors.pop());
            }
            if ((maxProcessors > 0) && (curProcessors < maxProcessors)) {
                // if (debug >= 2)
                // log("createProcessor: Creating new processor");
                return (newProcessor());
            } else {
                if (maxProcessors < 0) {
                    // if (debug >= 2)
                    // log("createProcessor: Creating new processor");
                    return (newProcessor());
                } else {
                    // if (debug >= 2)
                    // log("createProcessor: Cannot create new processor");
                    return (null);
                }
            }
        }

    }

    

    
    /**
     * Create and return a new processor suitable for processing HTTP
     * requests and returning the corresponding responses.
     */
    private HttpProcessor newProcessor() {

        //        if (debug >= 2)
        //            log("newProcessor: Creating new processor");
        HttpProcessor processor = new HttpProcessor(this, curProcessors++);
        if (processor instanceof Lifecycle) {
            try {
                ((Lifecycle) processor).start();
            } catch (LifecycleException e) {
                log("newProcessor", e);
                return (null);
            }
        }
        created.addElement(processor);
        return (processor);

    }


       /**
     * The background thread that listens for incoming TCP/IP
     *connections and
     * hands them off to an appropriate processor.
     */
    public void run() {

        // Loop until we receive a shutdown command
        while (!stopped) {

            // Accept the next incoming connection from the server socket
            Socket socket = null;
            try {
                //                if (debug >= 3)
                //                    log("run: Waiting on serverSocket.accept()");
                socket = serverSocket.accept();
                //                if (debug >= 3)
              
            } catch (Exception e) {
              continue;
            }

            // Hand this socket off to an appropriate processor
            HttpProcessor processor = createProcessor();
            if (processor == null) {
                try {
                     socket.close();
                } catch (IOException e) {
                    ;
                }
                continue;
            }
            //            if (debug >= 3)
            //                log("run: Assigning socket to processor " + processor);
            processor.assign(socket);    
        }

    }