Reaching outward from a multiply-nested class

^[37]It doesn’t matter how deeply an inner class may be nested—it can transparently access all of the members of all the classes it is nested within, as seen here:

//: c08:MultiNestingAccess.java
// Nested classes can access all members of all
// levels of the classes they are nested within.

class MNA {
  private void f() {}
  class A {
    private void g() {}
    public class B {
      void h() {
        g();
        f();
      }
    }
  }
}

public class MultiNestingAccess {
  public static void main(String[] args) {
    MNA mna = new MNA();
    MNA.A mnaa = mna.new A();
    MNA.A.B mnaab = mnaa.new B();
    mnaab.h();
  }
} ///:~

You can see that in MNA.A.B, the methods g( ) and f( ) are callable without any qualification (despite the fact that they are private). This example also demonstrates the syntax necessary to create objects of multiply-nested inner classes when you create the objects in a different class. The “.new” syntax produces the correct scope, so you do not have to qualify the class name in the constructor call.

Thinking in Java
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