Struts 1.x Action classes ThreadSafe?

Question

Can anyone explain, if Struts Action classes are threadsafe in Struts 1.x.

• Does RequestProcessor creates new instance of ActionClass for every new request.
• Does it cache the Action classes and reuses it for subsequent requests?

Answer 1

It caches the instance of an Action class and reuses it for subsequent requests.

You can check out the code here: org.apache.struts.action.RequestProcessor.process(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException

So, they are not thread-safe.

Answer 2

In fact, Struts 1.x is stateless. But if you include instance variables in your Action's not anymore (Not recomended), because the same instance is used. You can see the behavior of Struts 1.x if you enable the log level to TRACE.