Spring MVC access form data - spring

Question

I am new to spring mvc but I would like to know how I can access the data that the user inputs in a form.
these are some code snippets:
My controller
#Override
protected Object formBackingObject(HttpServletRequest request) throws Exception {
return new A();
}
where A is the class containing the 'model' that the form should return.
My view
<%# taglib prefix="form" uri="http://www.springframework.org/tags/form" %>
<%# taglib prefix="spring" uri="http://www.springframework.org/tags"%>
<form:form>
<table>
<tr>
<td><form:label path="amount">Amount:</form:label></td>
<td><form:input path="amount"/></td>
<td><form:errors path="amount"/></td>
</tr>
... some more fields
<tr>
<td><form:label path="message">Message:</form:label></td>
<td><form:input path="message"/></td>
<td><form:errors path="message"/></td>
</tr>
<tr>
<td colspan=3 align=right>
<button type="submit">Transfer</button>
</td>
</tr>
</table>
</form:form>
Q: How and where can I access the amount and message field in my controller to perform some action with the data? (perhaps after validating).

Answer 1

Appearently, the model was available in the onSubmit method:
#Override
protected ModelAndView onSubmit(HttpServletRequest request,HttpServletResponse response,
Object command, BindException errors) throws Exception {
ModelAndView mv = super.onSubmit(request,response,command,errors);
//TODO: SOME VALIDATING
A smth = (A)command;
//Do something with your object
return mv;
}

Answer 2

I assume class A has attributes amount and message with appropriate getters and setters.
Your controller method should then look like :
#RequestMapping("/url/for/the/form/action")
public String formBackingObject(#ModelAttribute A a, BindingResult error) {
// Spring automagically creates a A object and loads it with form parameters
// do you stuff, call services methods
return "viewname";
}
viewname is the name of the view, or can be "redirect:/other/url" if you use the post-redirect-get pattern.