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Variables scope

Julio Carlos
Greenhorn

Joined: Mar 26, 2002
Posts: 9
Ok. I have some questions:
The local variables and method aruments are thread safe?
How I can use and how work the SingleThreadModel?
Is a god idea use the service method in a Servlet derivated from HttpServlet?
ThX for your help.
JcSO
William Brogden
Author and all-around good cowpoke
Rancher

Joined: Mar 22, 2000
Posts: 12803
    
    5
1. yes, local variables are thread safe
2. you just declare that the servlet implements SingleThreadModel - the servlet engine does the rest automatically.
3. why would you want to? Inheriting from HttpServlet is done so you can use doPost, etc. People doing special processing of non-HTTP requests override service.
Bill
Julio Carlos
Greenhorn

Joined: Mar 26, 2002
Posts: 9
ThX for your help William, i have another question:
In my actual application i have a socket connection and DB connection, but i open and close theses connections each time that i call my servlet, now i want use a pool for theses connections, which framework is recomended???
confused:
JcSO :
William Brogden
Author and all-around good cowpoke
Rancher

Joined: Mar 22, 2000
Posts: 12803
    
    5
I did a search at java.sun.com for "connection pool" and found a bunch of references. I don't have any particular recommendation.
Bill
Axel Janssen
Ranch Hand

Joined: Jan 08, 2001
Posts: 2164
you can reuse at least database connection if you initialize them in the init() method of the servlet and destroy them in the destroy() method.
In another thread they said that apache.jarkarta.struts has a connction pool implemented. Why not use struts or trying to understand their connection pool implementation?
Andres Gonzalez
Ranch Hand

Joined: Nov 27, 2001
Posts: 1561
Julio Carlos??? hhmmm.. this really is a Latin Name. The first latin person I've seen around since I joined this great community... good to see new people around.
cheers


I'm not going to be a Rock Star. I'm going to be a LEGEND! --Freddie Mercury
jawa lal
Ranch Hand

Joined: Jul 12, 2001
Posts: 38
I have point to make , if local variable are referanceing some common object, i.e if two variable point to same object, than it may not be Thread safe


JAWA<br />(Jawahar Lal)
Axel Janssen
Ranch Hand

Joined: Jan 08, 2001
Posts: 2164
Originally posted by jawa lal:
I have point to make , if local variable are referanceing some common object, i.e if two variable point to same object, than it may not be Thread safe

Jawa,
there are no threading-problems with local variables in the service() method of servlets:
For every incoming doGet, doPost request the Servlet-Container spawns up a new thread.
 
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subject: Variables scope