jsf - How to prevent a a null value as the new value for ValueChangedEvent? -

jsf - How to prevent a a null value as the new value for ValueChangedEvent? -

inside input type field have value binding variable(lets phone call foo) of type double value property in jsp . have setter , getter foo , there valuechangedlistener registered input . autosubmit attribute of field set true . when user clears input , navigates next field ,the code within valuechangedlistener gets invoked , newvalue of valuechangedevent coming null . how can prevent ?

i tried handling setter method seems setter not getting called , valuechangedlistener getting called first . doesn't spec setter should called first populate user edited value component , valuechangedlistener gets fired ?

p.s: using adf richinputtext input think not related adf core jsf machinery. hence not tagging adf question.

i need validate new value , not interested in old value.

a valuechangelistener wrong tool job. utilize normal validator. in order validate empty required fields, utilize required="true". in order skip custom validators on empty fields, add together next context param web.xml:

class="lang-xml prettyprint-override"><context-param> <param-name>javax.faces.validate_empty_fields</param-name> <param-value>false</param-value> </context-param>

the disadvantage skip @notnull/@notblank jsr303 bean validation, shouldn't harm if aren't using anyway.

also why setter won't called before valuechangelistener?

because old value otherwise lost , defeat purpose of value alter listener.

will validator run before valuechangedlistener ? guess when validation passes , should invoke valuechangedevent , right ?

that's correct. value alter listener invoked when component has passed validation (i.e. uiinput#isvalid() returns true). noted should 1 time again when you're not interested in old value, value alter listener wrong tool job had in mind.

jsf jsf-2