Sorry for the long email.

I am using Tomcat 4.124 for my servlet engine and IIS for my web server.

I am monitoring exceptions that occur in my system and this one has me
confused. The exception is:
java.lang.NullPointerException
 at ParentClass.getQualificationMessage(ParentClass.java:483)
 at ChildClass.finishDocumentUpload(ChildClass.java:135)
 at ...

The parent class method is failing when it tries to call a method on the
Position object that it retrieved from the session.
It looks like the Position object is null in the session:

  protected static final String getQualificationMessage(
       HttpServletRequest request){
    HttpSession session = request.getSession();
    int employerId = ((Integer)session.getAttribute(RC.EMPLOYER_ID))
       .intValue();
(483)     int positionId
          =
((Position)session.getAttribute(RC.POSITION)).getPositionId();
   ...

What I can't explain is that the ChildClass method that has called the above
method was able to retrieve the position object from the session and call a
method on it. That makes me believe that the position object existed in the
session at that time:


I have a Position object stored as a session attribute with the attribure
name RC.POSITION.

  protected static final String finishDocumentUpload(
       HttpServletRequest request, EmployerConfiguration ec){
    HttpSession session =request.getSession();  
    Position position = (Position)session.getAttribute(RC.POSITION);
    if (position.attachDocumentsOnly()){
     return  forwardToOriginalPage(request, ec);
    } else {              
135      return getQualificationMessage(request);
   }          
  }


I cannot reproduce this error (which is making me crazy), but I see similar
things happening every once in a while in my exception log.

Any ideas?

Thanks for your help,
-tim