Making a JSF/Primefaces Field required based on condition

JSF required attribute based on condition for jsf or primeface component required="true" then

required="#{not empty bean.value1}" />
or
 required="#{bean.value1 != ' '}" />
or
 required="#{bean.value1 = = ' '}" />
or
if bean.vale is boolean

 required="#{bean.value3?true:false}" />
conditinal expression you can use