Common HTTP 1.1 Response 

Headers (Continued)

Location

The URL to which browser should reconnect.

Use sendRedirect instead of setting this directly. 

Refresh

The number of seconds until browser should reload page. 

Can also include URL to connect to.  See following 

example.

Set Cookie

The cookies that browser should remember. Don't set this 

header directly; use addCookie instead.

WWW Authenticate

The authorization type and realm needed in Authorization 

header. See details in More Servlets & JavaServer Pages.

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Servlets

www.corewebprogramming.com

Persistent Servlet State and 

Auto Reloading Pages

Idea: generate list of large (e.g., 150 digit) 

prime numbers

Show partial results until completed

Let new clients make use of results from others

Demonstrates use of the Refresh header

Shows how easy it is for servlets to 

maintain state between requests

Very difficult in traditional CGI 

Also illustrates that servlets can handle 

multiple simultaneous connections

Each request is in a separate thread

Synchronization required for shared data

64

Servlets

www.corewebprogramming.com

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