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private varibles in servlet

sitaram irrinki
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Joined: Feb 16, 2005
Posts: 158
can we write private variables in servlet?if yes how they are managed by multiple threads?
Makarand Parab
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Joined: Dec 10, 2004
Posts: 121
If it is a private instance variable, that variable will be shared by all the threads. Having a instance variable in servlet is highly discouraged. Well i never define one.
If you define a variable inside the service, dopost, doget methods as it is a local variable for the method, it gets created per thread and is blown off when the method ends.

Hope it makes sense
Let me know if i am wrong.

Makarand Parab
Scott Duncan
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Joined: Nov 01, 2002
Posts: 364
Makarand is correct. Object vars are not thread safe in a servlet. static final is OK and possibly even variables that are ONLY initialized in the init method and therefore not changed. If this is a concern make them member/method vars where they will be thread safe.

No more rhymes! I mean it!<br /> <br />Does anybody want a peanut?
I agree. Here's the link:
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