Answer is B

B is the answer

Answer is B, tested, NPE happens since Supplier provides null.

NullPointerExcepiton

Answer is B, class Job { String name; Integer cost; Job(String name, Integer cost) { this.name = name; this.cost = cost; } public String getName() { return name; } public int getCost() { return cost; } } public class Test { public static void main (String[] args) throws InterruptedException, ExecutionException { Job j1 = new Job("IT", null); DoubleSupplier dS = j1::getCost; System.out.println(j1.getName() + ": " + dS.getAsDouble()); } }

B,tested.If we replace Integer(object) with int(primitive) answer is D.

When I change int getCost() to Integer getCost() I thought DoubleSupplier line would fail compilation but it continued to work, anyone know why?

The answer is B tested.