Knockout js form submit to spring controller - spring-mvc

Question

How to pass form parameters into spring controller.
I need to submit the below form into this url "submit.htm".
<form data-bind="submit: save" action="forms/submit.htm" method="post">
<fieldset>
<legend>User: <span data-bind='text: errors().length'></span> errors</legend>
<label>First name: <input data-bind='value: firstName'/></label>
<label>Last name: <input data-bind='value: lastName'/></label>
</fieldset>
<button type="submit">Go</button>
</form>
JS:
var viewModel = {
firstName: ko.observable().extend({
required: true,
minLength: 2,
maxLength: 10
}),
lastName: ko.observable().extend({
required: true
}),
tasks: ko.observableArray([]),
save: function() {
if (viewModel.errors().length == 0) {
ko.utils.postJson($("form")[0], this);
} else {
alert('Please check your submission.');
viewModel.errors.showAllMessages();
}
}
};
viewModel.errors = ko.validation.group(viewModel);
ko.applyBindings(viewModel);
this is going to my controller.
But I didnot get those parameters in my controller. Also I dont know the way to get these params in my controller.