How to validate empty value which is double type in jsf? -

How to validate empty value which is double type in jsf? -

i have jsf input text double type in pojo class. want validate field empty check.by default in page load value comes 0.0 in text field.once clear value(i.e empty value) , click submit button, text field not getting validated.

any help appreciated.

if want appear empty can alter double (primitive) double (object)

and set field required="true"

jsf