声音模拟器 P143

animal类：

package homework;


public abstract class Animal {
abstract void cry();
abstract String getAnimalName();


}

Simulator 类：

package homework;


public class Simulator {
Animal animal;
public void playSound(Animal animal){
animal.cry();
System.out.println(animal.getAnimalName());
}



}

dog类：

package homework;


public class Dog extends Animal {
public String name;

public void cry(){
System.out.println("汪汪叫");
}
public String getAnimalName(){
return "狗狗";
}
}


cat类：

package homework;


public class Cat extends Animal {
public String name;

public void cry(){
System.out.println("喵喵叫");
}
public String getAnimalName(){
return "猫猫";
}
}


Application类：

package homework;


public class Application {


public static void main(String[] args) {
Simulator simulator=new Simulator();

simulator.playSound(new Dog());
simulator.playSound(new Cat());

}


}