horrorflick.java

来自「think in java TIJ-3rd-edition-code.zip」· Java 代码 · 共 40 行

//: appendixa:HorrorFlick.java
// You can insert Cloneability 
// at any level of inheritance.
package appendixa;
import com.bruceeckel.simpletest.*;
import java.util.*;

class Person {}
class Hero extends Person {}
class Scientist extends Person 
    implements Cloneable {
  public Object clone() {
    try {
      return super.clone();
    } catch(CloneNotSupportedException e) {
      // this should never happen:
      // It's Cloneable already!
      throw new InternalError();
    }
  }
}
class MadScientist extends Scientist {}

public class HorrorFlick {
  public static void main(String[] args) {
    SimpleTest monitor =
      new SimpleTest("appendixa.HorrorFlick");
    Person p = new Person();
    Hero h = new Hero();
    Scientist s = new Scientist();
    MadScientist m = new MadScientist();

    // p = (Person)p.clone(); // Compile error
    // h = (Hero)h.clone(); // Compile error
    s = (Scientist)s.clone();
    m = (MadScientist)m.clone();
    monitor.expect(new String[] {
    });
  }
} ///:~