<error-page> is not working for servlet

Question

when exception in servlet then is not working but for jsp its work properly

web.xml code

<error-page>
<exception-type>java.lang.Throwable</exception-type>
<location>/error.jsp</location>
</error-page>

servlet code

protected void processRequest(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException 
{
        response.setContentType("text/html;charset=UTF-8");
        PrintWriter out = response.getWriter();
        try {
            /*
             * TODO output your page here. You may use following sample code.
             */
          String a=null;
          a.toString();//this line will throw exception
        } 
finally {            
            out.close();
        }
}

it does not redirect to error.jsp

Answer 1

Servlet code this will throw the exception to the general error page

protected void processRequest(HttpServletRequest request, HttpServletResponse response)
                throws ServletException, IOException {
           // response.setContentType("text/html;charset=UTF-8");
            PrintWriter out = response.getWriter();
            try {
                /*
                 * TODO output your page here. You may use following sample code.
                 */
               String a=null;
               a.toString();

            }
            catch(Exception e)
            {
                throw new ServletException(e);
            }

            finally {            
                //dont write out.close();
            }
        }