helloworld.java

利用多态性编程

//编制自己的一个类，并放在自定义的包中
//三种动物的叫声，是否是哺乳动物，是否是食肉动物。分别输出。

//学生：刘建强    03312008
import seck.*;
public class HelloWorld{
    public static void main(String[] args) {
       dog obj1 = new dog();
       cat obj2 = new cat();
       duck obj3= new duck();
       
     System.out.println("在本类中可以访问下面所有的信息：");
     System.out.println("A dog says " +obj1.getHello());
     System.out.println("is carnivorous: " +obj1.isCarnivorous());
     System.out.println("is a mammal: " +obj1.isAMammal());
     System.out.println("A cat says " +obj2.getHello());
     System.out.println("is carnivorous: " +obj2.isCarnivorous());
     System.out.println("is a mammal: " +obj2.isAMammal());
     System.out.println("A duck says " +obj3.getHello());
     System.out.println("is carnivorous: " +obj3.isCarnivorous());
     System.out.println("is a mammal: " +obj3.isAMammal());
  }
}