Httpclient的简单示例!
Httpclient支持所有HTTP1.1 的HTTP nethod 包括:HttpGet,HttpHead, HttpPost, HttpPut, HttpDelete, HttpTrace, and HttpOptions.
URL 统一资源定位器(Uniform Resource locatron); URI 统一资源标识符(Uniform Resource Identifier)
httpclient的URIbuilder 用来简单的创建和修改RequestURIs
HTTPRESPONSE是请求后服务器返回的资源