i am trying to add two no. from the 1st two text boxes and display the sum in the 3rd text box after clicking the submit button and all work should be done on one single
jsp page.. please help
the
exception i am getting is mentioned below...
HTTP Status 500 -
type Exception report
message
description The server encountered an internal error () that prevented it from fulfilling this request.
exception
org.apache.jasper.JasperException: An exception occurred processing JSP page /index.jsp at line 23
20: <input type="text" name="t3"/><br>
21: <input type="submit" value="ADD"/>
22:
23: <% Integer a = Integer.valueOf(request.getParameter("t1"));
24: Integer b = Integer.valueOf(request.getParameter("t2"));
25: Integer c = Integer.valueOf(request.getParameter("t3"));
26: Integer o = a+b ;
Stacktrace:
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:510)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:419)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
org.netbeans.modules.web.monitor.server.MonitorFilter.doFilter(MonitorFilter.java:393)
root cause
java.lang.NumberFormatException: null
java.lang.Integer.parseInt(Integer.java:415)
java.lang.Integer.valueOf(Integer.java:553)
org.apache.jsp.index_jsp._jspService(index_jsp.java:72)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:377)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
org.netbeans.modules.web.monitor.server.MonitorFilter.doFilter(MonitorFilter.java:393)
note The full stack trace of the root cause is available in the Apache Tomcat/6.0.26 logs.
My jsp code is mentioned below...
<%--
Document : index
Created on : 14 Jul, 2011, 10:41:42 AM
Author : aNsH
--%>
<%@page contentType="text/html" pageEncoding="UTF-8"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>JSP Page</title>
</head>
<body>
<form action="index.jsp">
<input type="text" name="t1"/><br>
<input type="text" name="t2"/><br>
<input type="text" name="t3"/><br>
<input type="submit" value="ADD"/>
<% Integer a = Integer.valueOf(request.getParameter("t1"));
Integer b = Integer.valueOf(request.getParameter("t2"));
Integer c = Integer.valueOf(request.getParameter("t3"));
Integer o = a+b ;
session.setAttribute("add", o);
%>
<% if(c==null) {
%>
<input type="text" name="t3" value="<%=session.getAttribute("add") %>"/><br>
<%} %>
</form>
</body>
</html>