// exceptions/BetterNullPointerReports.java
// (c)2021 MindView LLC: see Copyright.txt
// We make no guarantees that this code is fit for any purpose.
// Visit http://OnJava8.com for more book information.
// {NewFeature} Since JDK 15

class A {
  String s;
  A(String s) {
    this.s = s;
  }
}

class B {
  A a;
  B(A a) {
    this.a = a;
  }
}

class C {
  B b;
  C(B b) {
    this.b = b;
  }
}

public class BetterNullPointerReports {
  public static void main(String[] args) {
    C[] ca = {
      new C(new B(new A(null))),
      new C(new B(null)),
      new C(null),
    };
    for(C c: ca) {
      try {
        System.out.println(c.b.a.s);
      } catch(NullPointerException npe) {
        System.out.println(npe);
      }
    }
  }
}