Neither BindingResult nor plain target object for bean name 'user' available as request attribute

I got the Neither BindingResult nor plain target object for bean name 'user' available as request attribute exception when ever there is a form:input path tag in my jsp

Can you please tell me the solution for this

provide some code snippet...

Controller

public class UserDtls extends SimpleFormController {



protected ModelAndView processFormSubmission(HttpServletRequest request,
HttpServletResponse response, Object command, BindException errors)
throws Exception {
User user=(User)command;
System.out.println("User name is "+user.getUserName());
System.out.println("User location is "+user.getLocation());

return new ModelAndView("First","user",user);

}
}


Mapping in Dispatcher Servlet
<bean id="userDtls" class="com.training.controller.UserDtls">
<property name="commandName">
<value>user</value>
</property>
<property name="commandClass">
<value>com.training.beans.User</value>
</property>
<property name="formView">
<value>welcome</value>
</property>


</bean>


Code in the jsp

<form:form name="user" commandName="user" action="user.htm" method="post">

Welcome To Spring Training

Name<form:input path="userName"/>

<input type="submit" value="submit">

</form:form>

Thank for your reply

Use the constructor

I tried the above constructor code but it is not working. Can I solve my problem with out using annotation. Can you please tell me the good tutorial for learning springs