Review: Generating the HTTP 

Response (Continued)

Most important status codes

200 (default)

302 (forwarding; set via sendRedirect)

401 (password needed)

404 (not found; set via sendError)

Most important headers you set directly

Cache Control and Pragma

Content Encoding

Content Length

Expires

Refresh

WWW Authenticate

101

Servlets

www.corewebprogramming.com

Review: Handling Cookies

Cookies involve name/value pairs sent from 

server to browser and returned when the 

same page, site, or domain is visited later

Let you

Track sessions (use higher level API)

Permit users to avoid logging in at low security sites

Customize sites for different users

Focus content or advertising

Setting cookies

Cookie constructor, set age, response.addCookie

Reading cookies

Call request.getCookies, check for null, look through 

array for matching name, use associated value

102

Servlets

www.corewebprogramming.com

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