How does Session work in JSP?

In JSP, Session is a mechanism used to store user data on the server side. When a user visits a website, the server creates a Session object for each user and assigns a unique Session ID. This Session ID is stored in the user’s browser, typically in the form of a cookie.

When users interact with the server, the server uses a Session ID to identify the user and stores the user’s data in the corresponding Session object. This allows various requests made by the user during the same session to share this data without the need for resubmission.

The working principle of Session can be summarized in the following steps:

1. When a user visits a website, the server will create a Session object for them and generate a unique Session ID.
2. The server will send this Session ID to the user’s browser, usually stored in the form of a cookie.
3. Users will carry the same Session ID for various requests within the same session so that the server can identify them.
4. The server uses the Session ID to locate the corresponding Session object and store the user’s data within it.
5. During the conversation, users can access and modify their Session data at any time.
6. When users close the browser or when the session times out, the Session object will be destroyed and the user’s data will be cleared.

In summary, the functioning principle of Session in JSP is to store user data on the server side, allowing data sharing and transfer between users during the same session.