tomcat Connector 连接器

连接器的核心功能，本文去除非核心功能，留下整个程序的框架，便于理解。

1、接受连接请求

2.创建request,和response.

3.调用容器对应的Invoke方法，

 首先看类的依赖结构。

1.Connetor 构造方法，根据具体的协议名字，创建协议处理器，主要有NIO,BIO，AJP,协议。如果要自定义协议处理剂最重要的协议处理器了。如图，协议处理需要实现ProtocoHandler接口，

 构造函数 输入为协议名称

 public Connector(String protocol) {
        setProtocol(protocol);
        // Instantiate protocol handler
        ProtocolHandler p = null;
        try {
            Class<?> clazz = Class.forName(protocolHandlerClassName);
           // 实例化一个协议处理器
            p = (ProtocolHandler) clazz.newInstance();
        } catch (Exception e) {
            log.error(sm.getString(
                    "coyoteConnector.protocolHandlerInstantiationFailed"), e);
        } finally {
            this.protocolHandler = p;
        }

        if (!Globals.STRICT_SERVLET_COMPLIANCE) {
            URIEncoding = "UTF-8";
            URIEncodingLower = URIEncoding.toLowerCase(Locale.ENGLISH);
        }
    }

2.createRequest 和相应  此处不仔细深入。很简单。就是创建请求和相应对象

 public Request createRequest() {

        Request request = new Request();
        request.setConnector(this);
        return (request);

    }


    /**
     * Create (or allocate) and return a Response object suitable for
     * receiving the contents of a Response from the responsible Container.
     */
    public Response createResponse() {

        Response response = new Response();
        response.setConnector(this);
        return (response);

    }

3.启动和关闭。是默认方法；

protected void startInternal() throws LifecycleException {

        // Validate settings before starting
        if (getPort() < 0) {
            throw new LifecycleException(sm.getString(
                    "coyoteConnector.invalidPort", Integer.valueOf(getPort())));
        }

        setState(LifecycleState.STARTING);

        try {
            protocolHandler.start();
        } catch (Exception e) {
            String errPrefix = "";
            if(this.service != null) {
                errPrefix += "service.getName(): "" + this.service.getName() + ""; ";
            }

            throw new LifecycleException
                (errPrefix + " " + sm.getString
                 ("coyoteConnector.protocolHandlerStartFailed"), e);
        }
    }

protected void stopInternal() throws LifecycleException {

setState(LifecycleState.STOPPING);

try {
protocolHandler.stop();
} catch (Exception e) {
throw new LifecycleException
(sm.getString
("coyoteConnector.protocolHandlerStopFailed"), e);
}
}

我们从代码看到ProtocoHandler的重要性了明天再看