Servlet—07—Cookie; Seesion;

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A, Cookie

Before learning Cookie, we look first to write a servlet class, concrete steps to override the parent class service approach:

. 1  -Service ()
 2  {
 . 3      // Setup Request encoding format
 4      // set the response encoding format
 5      // acquiring request information
 6           // Get cookie data
 7      // processing request information
 8      // response processing result
 9          // create cookie data
 10  　  　// response cookie data　　
 11         // 1. direct response to
 12         @ 2 forwards the request to another servlet class
 13         // 3. the redirection     
14   }              

You may full of questions about the cookie, do not worry, we have now come to understand Cookie!

1. Problem:
　　different data requests use the same request, but as long as the end of the request, the data is destroyed, other requests will need to resend a common data; so, each time re-fill data, very troublesome! There is no good way, often need to fill in the data, stored it?
2. Resolution:
　　Yes, that is the use of cookie technology!
3. Features:
　　(1) command the server, the browser stores the data;
　　(2) data that needs to be stored is declared on the server side, as to tell the browser in response;
　　(3) is not provided on the valid browser is closed fail;
　　(4) inappropriate storage of large amounts of data;
4. action:
　　the problem of data sharing between different requests of the problem.

 

 

Two, Cookie code implementation