Error without handler
//File Name: generateErrorNoHandler.jsp <%-- This scriptlet checks a hidden field to see whether or not to throw an exception --%> <% String hiddenField = request.getParameter("hiddenValue"); if ( hiddenField.equals("error")) throw new java.lang.NullPointerException(); %> <HTML> <HEAD><TITLE>Generate Error</TITLE></HEAD> <BODY> This page generates an error when you click the button.<P> <FORM METHOD="POST" ACTION="generateErrorNoHandler.jsp"> <INPUT TYPE="HIDDEN" NAME="hiddenValue" VALUE="error"> <INPUT TYPE="SUBMIT" VALUE="Generate exception!"> </FORM> </BODY> </HTML>