JSP State Management

no stateful HTTP protocol

Stateless means that when the browser sends a request to the server, the server responds to the client request.

But when the same browser sends the request to the server again, the server does not know that it is just that browser.

Simply put, the server is not going to remember you, so it is a stateless protocol.

two major mechanisms for saving User state (Session/cookie)

What is a cookie?

is a series of text messages that the Web server holds on the client.

Typical application one: Determine whether the registered user has logged on to the website

Typical application two: "Shopping cart" processing

The role of Cookies

Tracking for a specific object

Save user Web browsing history and habits

Simplified Login

Security risk: Easy disclosure of user information

Creation and use of cookies

Create a Cookie Object

Cookie Newcookie = new Cookie (String key, Object value);

Write Cookie Object

Response.addcookie (Newcookie);

Read Cookie Object

cookie[] cookies = request.getcookies ();

Common methods

Session vs. Cookie

JSP State Management