A use JBoss 3.2.3(include Tomcat 4.1.29).
By default Tomcat web container uses one instance of servlet per many requests. I can't use SingleThreadModel for my servlets because It does not approach for my problem.
In Servlet Specification Version 2.4 I have found:
For a servlet not hosted in a distributed environment (the default), the servlet container must use only one instance per servlet declaration.
In the case where a servlet was deployed as part of an application marked in the deployment descriptor as distributable, a container may have only one instance per servlet declaration per Java Virtual Machine (JVM TM). (MY CASE)
Whether is it possible to force JBoss(Tomcat web container) to use new instance of servlet for each http request. (for each new http request create new servlet instance)?
Create a 'dummy'servlet to get the request. In this servlet, create an instance of a plai java-class hat does all processing.
If you have any 'persistent' references in your serlet that is set during init(), pass those on as creation-parameters to your 'servlet'-class.