关于Logger,Tomcat 的Logger是如何工作的

HttpProcessor.java

private HttpConnector connector = null;

    private void log(String message) {

        Logger logger = connector.getContainer().getLogger();

        if (logger != null)

            logger.log(threadName + " " + message); //为什么这句话可以用？往下推论

}

HttpProcessor.java

    public HttpProcessor(HttpConnector connector, int id) {

        super();

        this.connector = connector;

        this.debug = connector.getDebug();

        this.id = id;

        this.proxyName = connector.getProxyName();

       this.proxyPort = connector.getProxyPort();

        this.request = (HttpRequestImpl) connector.createRequest();

        this.response = (HttpResponseImpl) connector.createResponse();

        this.serverPort = connector.getPort();

        this.threadName =

          "HttpProcessor[" + connector.getPort() + "][" + id + "]";

    }

HttpConnector.java

    private HttpProcessor newProcessor() {

        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);

    }