Servlet Study 1

this content below are come from the  JSR154 by sun

Just for record purpose. if this relate to some law problem ,please contact with  me, my email iszbwork000@163.com

What is a Servlet?

A servelt is a java technology-based Web component,managed by a container that generates dynamics content.

Servlet interact with web clients via a request/response  paradigm implemented by the servlet container.

What is a servlet container?

The servlet container is a part of a web server  or a application server that provides the network services over which requests and response are sent

decodes MIME-based requests, and formats MIME-based responses ,A servlet container also  contains and manages servlets through their lifecycle.

A typical sequence of event

1,A client access a Web server and makes an http request.

2,The request is received by the Web server and hand off to the servlet container.The servlet container can be running in the same process as the host Web server,

in a different process on the same host,or on a different host from the Web server for which it processes requests

3,The servlet container determines which servlet to invoke based on the configuration of its servlets ,and calls it with objects representing the request and response.

4,The servlet uses the request object to find out who the remote user is ,what http post parameters may have been sent as part of this request.and other relevant data

The servlet performs whatever logic it was programmed with,and generates data to send back to the client via the response object

5 once the servlet has finished processing the requet ,the servlet container ensures that the response is properly flushed  and returns control bakc to the host Web server