bigegg2.java

来自「think in java TIJ-3rd-edition-code.zip」· Java 代码 · 共 45 行

//: c08:BigEgg2.java
// Proper inheritance of an inner class.
import com.bruceeckel.simpletest.*;

class Egg2 {
  protected class Yolk {
    public Yolk() {
      System.out.println("Egg2.Yolk()");
    }
    public void f() {
      System.out.println("Egg2.Yolk.f()");
    }
  }
  private Yolk y = new Yolk();
  public Egg2() {
    System.out.println("New Egg2()");
  }
  public void insertYolk(Yolk yy) { y = yy; }
  public void g() { y.f(); }
}

public class BigEgg2 extends Egg2 {
  public class Yolk extends Egg2.Yolk {
    public Yolk() {
      System.out.println("BigEgg2.Yolk()");
    }
    public void f() {
      System.out.println("BigEgg2.Yolk.f()");
    }
  }
  public BigEgg2() { insertYolk(new Yolk()); }
  public static void main(String[] args) {
    SimpleTest monitor =
      new SimpleTest("BigEgg2");
    Egg2 e2 = new BigEgg2();
    e2.g();
    monitor.expect(new String[] {
      "Egg2.Yolk()",
      "New Egg2()",
      "Egg2.Yolk()",
      "BigEgg2.Yolk()",
      "BigEgg2.Yolk.f()"
    });
  }
} ///:~