java - How to prevent the function passed to Optional's orElse from being executed when the Optional is not empty? -


if i'm calling function orelse, function executed if optional not empty. there way restrict execution of function when optional empty? 

optional.ofnullable(somevalue).orelse(somefunction());

somefunction() gets executed since it's argument passed method, , arguments passed method evaluated before method executed. avoid execution, should pass somefunction() within supplier instance.

use orelseget instead of orelse :

optional.ofnullable(somevalue).orelseget(someclass::somefunction);

or

optional.ofnullable(somevalue).orelseget(()->somefunction());

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