3 fiels form based login authentication in Tomcat

Hi

I want Tomcat authentication like company id / username / Password so it looks i should go for Form based authentication ....

1) I wrote login.jsp and error.jsp ;

2)web.xml

<login-config>

<auth-method>FORM</auth-method>

<realm-name>MyFirst Protected Area</realm-name>

<form-login-config>

<form-login-page>/login.jsp<;/form-login-page>

<form-error-page>/error.jsp<;/form-error-page>

</form-login-config>

</login-config>

3 )configured Realm in server.xml of tomcat className="org.apache.catalina.realm.DataSourceRealm";

Now issue is tomcat handles this j_security_check action and i want the j_companyid field in my application ... so how can i get it ....

Can we write an class that will process this authentication and pass insted of let tomcat handel it ?

OR

any configuration that can handel this j_companyid and pass on to application....?

Should we need to write our own Realm if so ....then how to ?

Thanks

Chetan

Login.jsp

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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">

<html>

<head>

<title>Login Page</title>

</head>

<body>

<h1>Login to MyFirst</h1>

<p>

If you have been issued a username and password, key them in here now!

</p>

<form method="POST" action="j_security_check">

CompanyID : <input type="text" size="15" maxlength="25" name="j_companyid"><br><br>

Username : <input type="text" size="15" maxlength="25" name="j_username"><br><br>

Password : <input type="password" size="15" maxlength="25" name="j_password"><br><br>

<input value="Login" type="submit"> <input value="Clear" type="reset">

</form>

</body>

</html>

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