public static final <X> Function<X,Boolean> isNullBy(final IFunction<X,?> by) {
        return FnFunc.chain(by, FnObject.isNull());
    }
public static final < X > Function < X , Boolean > isNullBy ( final IFunction < X , ? > by ) { return FnFunc . chain ( by , FnObject . isNull ( ) ) ; }
<p>
Determines whether the result of executing the
specified function on the target object is null or not.
</p>

@return true if the function result is null, false if not.