java学习之第五章编程题示例（初学篇）

/*
  Animal.java
*/
package animal;

public abstract class Animal {
 public    abstract void cry();
 public    abstract String getanimalName();
}

//Dog.java
package animal;

public class Dog extends Animal
{

    String aa="旺旺";
    String dog_name ="旺财";
    @Override
    public void cry() {
        // TODO Auto-generated method stub
        System.out.println("小狗的叫声"+aa);    
    }

    @Override
    public String getanimalName() {
        // TODO Auto-generated method stub
     return dog_name;
    } 
}

//Cat.java
package animal;

public  class Cat extends Animal
{
    String aa="喵喵";
    String bb="花花";
    @Override
    public void cry() {
        // TODO Auto-generated method stub
     System.out.println("小猫的叫声: "+aa);
    }

    @Override
    public String getanimalName() {
        // TODO Auto-generated method stub
        return bb;
    }
}

//Application.java
package animal;

public class Application {
    public static void main(String args[])
    {
      Simulator mysimulator =new Simulator();
      mysimulator.playSound(new Dog());
      mysimulator.playSound(new Cat());
    }
}

//Simulator.java
package animal;

public class Simulator {
    void playSound(Animal st)
    {
        System.out.println(st.getanimalName()+"的声音");
        st.cry();
    }
}