Question

Basically, how long is an instance of a servlet around for? I am kind of guessing it is session scope. However, I suppose it could have some sort of timeout or garbage collection to remove old instances.

Answer 1

• a servlet is created when the application starts (it is deployed on the servlet container) or when it is first accessed (depending on the load-on-startup setting)
• when the servlet is instantiated, the init() method of the servlet is called
• then the servlet (its one and only instance) handles all requests (its service() method being called by multiple threads). That’s why it is not advisable to have any synchronization in it, and you should avoid instance variables of the servlet
• when the application is undeployed (the servlet container stops), the destroy() method is called.