title: Race condition while using Stringbuffer as instance variable in servlet
body: <p>My code is like that</p>
  
  <pre><code>public class MyServlet extends Action
  {
      Stringbuffer s=null;
  
      public ActionForward execute(ActionMapping mapping, ActionForm form, HttpServletRequest req, HttpServletResponse res)
      {
  
          s = "hello";//or some dynamic value 
  
      }
  }
  </code></pre>
  
  <p>Here my question is whether this instance variable 's' would be thread safe or not.</p>
  
  <p>Any help would be appreciated.</p>
  
  <p>Thanks in advance</p>