Replacing repetitive get statement with Java 8 Optional

Question

I have a use case, where I have nested classes and an object of the top class. I want to get a value which is at the Nth level. I\'m using getters repetitively to achieve th

Answer 1

Use Optional with a series of map() calls for a nice one-liner:

String getAValue(D d) {
   return Optional.ofNullable(d)
       .map(D::getC).map(C::getB).map(B::getA).map(A::getA1).orElse(null);
}

If anything is null along the chain, including d itself, the orElse() will execute.