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1. doGet vs doPost
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µ±form¿òÀïÃæµÄmethodΪpostʱ£¬Ö´ÐÐdoPost·½·¨
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service()ÊÇÔÚjavax.servlet.Servlet½Ó¿ÚÖж¨ÒåµÄ, ÔÚjavax.servlet.GenericServletÖÐʵÏÖÁËÕâ¸ö½Ó¿Ú, ¶ø doGet/doPost ÔòÊÇÔÚ javax.servlet.http.HttpServlet
ÖÐʵÏÖµÄ, javax.servlet.http.HttpServlet ÊÇ
javax.servlet.GenericServlet µÄ×ÓÀà.
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ÆäʵËùÓеÄÇëÇó¾ùÊ×ÏÈÓÉ service() ½øÐд¦Àí, ¶øÔÚ javax.servlet.http.HttpServlet
µÄ service() ·½·¨ÖÐ, Ö÷Òª×öµÄÊÂÇé¾ÍÊÇÅжÏÇëÇóÀàÐÍÊÇ Get »¹ÊÇ Post, È»ºóµ÷ÓöÔÓ¦µÄ
doGet/doPost Ö´ÐÐ.”
2.Cookie vs Session
What is cookie:
1) It is essentially a piece of txt sent to the client from server
2) The client can prevent the server from writing cookie
3) A server can only get the cookie of itself
 
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