Validator

Validator itself has implement Interceptor interface, so it also is a interceptor,whose configuration model is the totally the same as validator.Following code is an example of Validator:

public class LoginValidator extends Validator {
    protected void validate(Controller c) {
        validateRequiredString("name", "nameMsg", "Please type usernmae");
        validateRequiredString("pass", "passMsg", "Please type password");
}
    protected void handleError(Controller c) {
        c.keepPara("name");
        c.render("login.html");
    }
}

validateXxx(...)series methods could be invoked in protected void validator(Controller c) to validate back-end.

In protected void handleError(Controller c), c.keepPara(...) method could be invoked to return value submitted by request to view to keep original input values.

Moreover, c.render(...) could be invoked to render corresponding page.

NOTE handleError(Controller c) only could be invoked when validation fails.

In above code, keepXxx in handleError method is used to keep values from form and pass them back to view, in order to avoid users inputing form fields again which have already validated. If model object is passed, keepModel could be used to keep data inputed by users.