How do servlets work?

Question

I write pairs of servlet programs, but I don’t think I fully understand how the servlet works. So, here are a couple of questions that I have:

All the code that I wrote about the servlet runs only on Netbeans with apache tomcat. When I run my html file that makes a request for a servlet, it usually gives an error saying that it cannot find the servlet, then I need to redistribute the servlet, then everything will work fine. It seems my servlet timeout after a while or something like that.

Does the servlet work all the time? The servlet has init () and destroy (), so I assume that it will not work all the time. So when does it start and when does it end? Does this start when there is a request from the client and does the wait time end? And as I fixed my problem, that I have to constantly reinstall the servlet. Many thanks.

Answer 1

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, destroy , , .

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Answer 2

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Answer 3

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Answer 4

- , init() destroy

init() , serlvet ( - tomcat)

destroy() ,

dopost() doGet() ( HTTP-)