Null pointer exception !!

[namrata suri]

http://viralpatel.net/blogs/2009/01/struts-validation-framework-tutorial-example-validator-struts-validation-form-validation.html/comment-page-1#comment-11662

I followed this tutorial and on running am getting the following error.

type Exception report

message

description The server encountered an internal error () that prevented it from fulfilling this request.

exception

org.apache.jasper.JasperException: java.lang.NullPointerException
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:522)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:416)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:337)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)


root cause

java.lang.NullPointerException
org.apache.struts.taglib.html.JavascriptValidatorTag.renderJavascript(JavascriptValidatorTag.java:367)
org.apache.struts.taglib.html.JavascriptValidatorTag.doStartTag(JavascriptValidatorTag.java:349)
org.apache.jsp.index_jsp._jspx_meth_html_005fjavascript_005f0(index_jsp.java:141)
org.apache.jsp.index_jsp._jspService(index_jsp.java:92)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:374)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:337)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)

I do not know where the nullpointer exception is occuring because on clicking on the line numbers- it says the line cannot be found.