In order to validate a form, an org.springframework.validation.Validator can be implemented for arbitrary form backing beans. The validation method populates an org.springframework.validation.Errors object with error messages, see MyFormValidator Example for a complete example.
if(form.getEmail() == null) {
errors.rejectValue(
"email",
"error-email-missing",
"The email address is missing."
);
}
The first argument passed to Errors#rejectValue() denotes the form bean
property (here: “email”) that is invalid. The following arguments are an error code (to
be defined in a resource bundle) and a default message.
Global errors affecting the entire form instead of a single property are supported, too.
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