##HTTP 消息的组成 起始行 消息头 空行 [可选的消息体]
##例子
GET 请求
GET /xxx/xxx/xxx.html HTTP/1.1
Accept: /
Accept-Language: zh-CN
User-Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; Trident/4.0; Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1) ; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; InfoPath.2; CIBA; Tablet PC 2.0)
Accept-Encoding: gzip, deflate
Host: www.xxxxx.com
Connection: Keep-Alive
Cookie: xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
[最后是空白行，必须有]
POST 请求
POST /submit.do HTTP/1.1
Accept: */*
Accept-Language: zh-CN
User-Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; Trident/4.0; Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1) ; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; InfoPath.2; CIBA; Tablet PC 2.0)
Accept-Encoding: gzip, deflate
Content-Type: application/x-www-form-urlencoded;charset=utf-8
Host: www.xxxxx.com
Connection: Keep-Alive
Cookie: xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
[空白行，必须有]
name=xxx&age=xxx&pwd=xxx
响应
HTTP/1.1 200 OK
Cache-Control: private
Content-Type: text/html; charset=utf-8
Content-Encoding: gzip
Server: nginx/1.11
Date: Mon, 20 Sep 2010 04:28:12 GMT
Content-Length: 55555
[空白行，必须有]
<html>....</html>
##Spring Boot不便于理解，新增spring-demo