Java EE (Java Enterprise Edition) General Discussion

hi,
i want to set List employees into session,but i was performing this using below code i am not able to do at all .i am getting hell NULL pointer exception

can anybody help me in resolving this please .itz again urgent

Thanx in advance

below is my code


public ActionForward getEmployees(ActionMapping mapping, ActionForm form, HttpServletRequest request, HttpServletResponse response) throws Exception {
populateEmployees(request);
List array=(List)request.getAttribute("employees");
session.setAttribute(Constants.EMPLOYEES,array);
return mapping.findForward(Constants.SUCCESS);
}

private void populateEmployees(HttpServletRequest request) {
List employees = empService.getAllEmployees();
request.setAttribute(Constants.EMPLOYEES, employees);

}