使用协议处理器

通常，HTTP协议处理器的作用是：在对接收到的报文执行应用相关的处理逻辑之前对其进行预处理，以及在对将要发出的报文在执行应用相关的逻辑之后进行处理

HttpProcessor httpproc = HttpProcessorBuilder.create()
// Required protocol interceptors
        .add(new RequestContent())
        .add(new RequestTargetHost())
        // Recommended protocol interceptors
        .add(new RequestConnControl())
        .add(new RequestUserAgent("MyAgent-HTTP/1.1"))
        // Optional protocol interceptors
        .add(new RequestExpectContinue(true))
        .build();

HttpCoreContext context = HttpCoreContext.create();
HttpRequest request = new BasicHttpRequest("GET", "/");
httpproc.process(request, context);

将请求发给目标主机，并得到应答

HttpResponse = <...>
httpproc.process(response, context);