Hi 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.
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?