JSP, Servlets

KK · Jan 22, 2009

Hello,

I am trying to make a simple jsp and servlet application. I am using
J2EE1.4 server.
I have a login form in the jsp file and in its action i have mentioned
the name of the Servlet.
My jsp and html files are working properly but my servlets are not.
I have even tried Apache Tomcat..but situation remains same.

Can anyone suggest me anything?

Thanks

mirko.ebert · Jan 22, 2009

Please lookt at the examples in Tomcat.

KK · Jan 22, 2009

When jsp page is forwarding to servlet page..its displaying a blank
page, if its not finding the servlet page then it should display
'Resource not found error' but it displays a blank page.

mirko.ebert · Jan 22, 2009

When jsp page is forwarding to servlet page..its displaying a blank
page, if its not finding the servlet page then it should display
'Resource not found error' but it displays a blank page.

Well, I think that is not the best Way to forward from a JSP to a
servlet. In my opinion, it's better to forward from a servlet to a
JSP. The the servlet works as a controller (MVC architecture). But
that's not the problem. Do you call the servelt via URL-pattern
(defined in the web.xml)? Can you post your web.xml? Can you also post
your forwarding code snippet.

mirko.ebert · Jan 22, 2009

Please check the Tomcat log file.

KK · Jan 22, 2009

THIS is the form of the jsp page. Login is the name of the servlet
file.

<form name="form" method="post" action="Login">
<table border="0">

<font color="#5F512F">

<tr>
<td><strong><font color="#5F512F">Username</font></strong></
td><td><input type="text" name="j_username" size="15" maxlength="25"></
td></tr>

<tr>
<td><strong><font color="#5F512F">Password</font></strong></
td><td><input type="password" NAME="j_password" size="15"
maxlength="25"></td></tr>

</table>

</strong><center><BR>
<input type="Submit" value="Submit">
           <input
type="Reset" value="Reset"></center>

</form>

KK · Jan 22, 2009

THIS is the XML file.

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee
http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
<display-name>WebApp</display-name>
<servlet>
<display-name>LoginServlet</display-name>
<servlet-name>LoginServlet</servlet-name>
<servlet-class>LoginServlet</servlet-class>
</servlet>
<servlet>
<display-name>login</display-name>
<servlet-name>login</servlet-name>
<jsp-file>/login.jsp</jsp-file>
</servlet>
<servlet-mapping>
<servlet-name>LoginServlet</servlet-name>
<url-pattern>/Login</url-pattern>
</servlet-mapping>
</web-app>

KK · Jan 22, 2009

THIS is the servlet file.

import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;

import javax.servlet.ServletException;
import javax.servlet.http.*;

public class LoginServlet extends HttpServlet
{
public LoginServlet()
{

}
protected void doPost(HttpServletRequest req,HttpServletResponse res)
throws ServletException,IOException
{
res.setContentType("text/html");
PrintWriter out = res.getWriter();
Connection c = null;
Statement st = null;
String username = req.getParameter("j_username");
System.out.println("<HTML>HELLO"+username+"</HTML>");
ResultSet rs= null;
System.out.println("Login Servlet");
try
{
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
c = DriverManager.getConnection("jdbc

dbc

ro","","");
st = c.createStatement();
rs = st.executeQuery("select * from login");
while(rs.next())
{
out.println(rs.getInt(1));
out.println(rs.getString(2));
}
}
catch(Exception e)
{
e.printStackTrace();
}
}
}

Its just a simple code, I wonder why its not displaying anything.

Arne Vajhøj · Jan 23, 2009

KK said:
THIS is the servlet file.

import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;

import javax.servlet.ServletException;
import javax.servlet.http.*;

public class LoginServlet extends HttpServlet
{
public LoginServlet()
{

}
protected void doPost(HttpServletRequest req,HttpServletResponse res)
throws ServletException,IOException
{
res.setContentType("text/html");
PrintWriter out = res.getWriter();
Connection c = null;
Statement st = null;
String username = req.getParameter("j_username");
System.out.println("<HTML>HELLO"+username+"</HTML>");
ResultSet rs= null;
System.out.println("Login Servlet");
try
{
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
c = DriverManager.getConnection("jdbcdbcro","","");
st = c.createStatement();
rs = st.executeQuery("select * from login");
while(rs.next())
{
out.println(rs.getInt(1));
out.println(rs.getString(2));
}
}
catch(Exception e)
{
e.printStackTrace();
}
}
}

Its just a simple code, I wonder why its not displaying anything.

To debug you need to look at the console output.

If you get an exception (which is what I think you get) then you
do not get any output because you catch it.

And if there are no records in the table, then you do not get any
output.

Arne

PS: Note that your HTML output is send to the console not the
browser !!

mirko.ebert · Jan 23, 2009

PS: Note that your HTML output is send to the console not the
browser !!

Thats right. Change System.out.println to out.println

Problem with tomcat 6.0.32	12	Sep 5, 2012
servlets and jsp doubt	10	Apr 13, 2010
newbie: JSP vs Servlets	10	Dec 29, 2006
JSP page not compiling	5	Feb 3, 2009
Servlets and JSP	5	May 26, 2006
Accessing Server File with Servlets	6	Sep 6, 2009
JSP/Servlets J2EE	2	Nov 20, 2004
Mapping My Path in Java Web Development: Crafting a Detailed Roadmap	0	Mar 9, 2024

JSP, Servlets

KK

mirko.ebert

KK

mirko.ebert

mirko.ebert

KK

KK

KK

Arne Vajhøj

mirko.ebert

Ask a Question

Similar Threads

Members online

Forum statistics

Latest Threads