The value for the useBean class attribute user.UserData is invalid.

I am trying to get the data by using bean where I am facing the problem while running it ...

<html>
<body>
<form method=post action = "UserSave.jsp">
Name<input type =text name=username size =20><br>
Email<input type=text name=email size=20><br>
Age <input type=text name=age size=4><br>
<input type=submit>
</form>
</body>
</html>
---------------------------
UserData---java

package user;
public class UserData {
String username;
String email;
int age;

public void setUsername( String value )
{
username = value;
}

public void setEmail( String value )
{
email = value;
}

public void setAge( int value )
{
age = value;
}

public String getUsername() { return username; }

public String getEmail() { return email; }

public int getAge() { return age; }
}
-------------------
<jsp:useBean id="user" class ="user.UserData" scope="session"/>
<jsp:setProperty name="user" property="*"/>
<html>
<body>
<a href="NewPage.jsp">continue </a>
</body>
</html>-------------UserSave.jsp
---------------------
<jsp:useBean id="user" class="user.UserData" scope="session"/>
<html>
<body>
You Entered <br>
Name:<%= user.getUsername() %><br>
E-mail:<%= user.getEmail() %><br>
Age : <%= user.getAge() %><br>
</body>
</html>------------NewPage.jsp
-------------------------------------------

org.apache.jasper.JasperException: /jsp/UserSave.jsp(1,1) The value for the useBean class attribute user.UserData is invalid.

org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:512)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:377)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264)
javax.servlet.http.HttpServlet.service(HttpServlet.java:810)
org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:96)

else this the url from where i am trying as an example
http://www.jsptut.com/Forms.jsp

Your user.UserData.class file is in:
<Application_Base>/<application_name>/WEB-INF/classes/user/
directory? It is spelled properly?

Hmm I have forgot to place the compile .class file under classes directory .now it working fine..........