Use this code to explicitly send an exception to the JSP error page from a servlet:
public void doPost(HttpServletRequest request, HttpServletResponse
response)
throws ServletException, IOException {
...
//Create your exception
Exception myException = new Exception ("error message");
//Set this request attribute
request.setAttribute("javax.servlet.jsp.jspException", myException );
//forward to the error page
RequestDispatcher rd =
request.getRequestDispatcher("/Error.jsp");
rd.forward(request, response);
}
The JSP error page simply accesses the implicit object exception to extract the error message.