JSP Tutorials - Herong's Tutorial Examples - v5.11, by Herong Yang
What Is a Cookie
This section describes what is a cookie - a small amount of information sent by a Web server to a Web browser, saved by the browser, and sent back to the server later.
What Is a Cookie?: A cookie is a small amount of information sent by a Web server to a Web browser, saved by the browser, and sent back to the server later. Cookies are transmitted inside the HTTP header.
Cookies move from server to browser, and back to server as follows:
Web Web Local Web Web Server Browser System Browser Server Send Receive Save Send back Receive cookies --> cookies --> cookies --> cookies --> cookies
As you can see from the diagram, cookies are actually saved to the memory or hard disk of Web browser user's machines. Many users are concerned about this. But I think it is pretty safe to allow your browser to use cookies.
If you are really concerned, you can change your browser's settings to reject cookies. But this may cause many Web based applications fail to run on your browser.
If you are using IE (Internet Explorer) on Windows, some cookies are stored in the Microsoft folder in your profile. You can look at them using a command window. But they are stored in multiple files in random names:
herong> dir \Users\herong\AppData\Roaming\Microsoft\Windows\Cookies> 378 MH1M64UB.txt 102 N31PUJ47.txt 210 E2N0HL2B.txt 74 VTX5T7K7.txt 100 D800RRJK.txt 199 YZI4VETO.txt ...
If you are using Firefox on Windows, some cookies are stored in the Mozilla folder in your profile. You can look at them using a command window. But they are stored in a SQLite data file:
herong> dir \Users\herong\AppData\Roaming\Mozilla\Firefox\Profiles \o1ri26bj.default\cookies.* 524,288 cookies.sqlite 32,768 cookies.sqlite-shm 0 cookies.sqlite-wal
Table of Contents
JSP (JavaServer Pages) Overview
Tomcat Installation on Windows Systems
Syntax of JSP Pages and JSP Documents
►Managing Cookies in JSP Pages
Sending and Receiving Cookies in JSP Pages
Persistent Cookies Stored on Hard Disk
Persistent Cookie Test Example
Space Character not Allowed in Cookie Value
Dumping HTTP Response with Cookies
JavaBean Objects and "useBean" Action Elements
Managing HTTP Response Header Lines
Non-ASCII Characters Support in JSP Pages
Overview of JSTL (JSP Standard Tag Libraries)
Multiple Tags Working Together
Using Tomcat on CentOS Systems
Connecting to SQL Server from Servlet