重载与重写

package polymorphic;

public class Test {
	public static void main(String[] args) {
		show(new Cat());
		show(new Dog());
		System.out.println("-------------");
		Animal a = new Cat();
		a.eat();
		a.eat(3);
		//a.work();
		Cat b = (Cat)a;
		b.sport();
		
		Animal a2 = new Dog();
		a2.eat();
		//a.work();
		Dog b2 = (Dog)a2;
		b2.sport();		
		
		Work d = new Work();
		d.work();
		
		Work f = new Cat2();
		f.work();
	}
	
	public static void show(Animal a) {
		a.eat();
		if(a instanceof Cat) {
			Cat c = (Cat)a;
			c.sport();
		}else if (a instanceof Dog) {
			Dog c = (Dog)a;
			c.sport();
		}
	}

}
class Work{
	public void work() {
		System.out.println("Catch mice");
	}	
}
abstract class Animal{
	public abstract void eat() ;

	public void eat(int num) {
		System.out.println("[重载1eat rice]");
		for(int i = 0; i < num; i++)
			System.out.println("[重载1eat rice]");
	}
}
 class Cat2 extends Work{
	public void way() {
		System.out.println("重写");
	}
	
	public void work() {
		System.out.println("[重写 again]");
	}
}
class Cat extends Animal{
	 //int num = 2;
	//System.out.println("Hi, I am a Cat.");
	public void eat() {
		System.out.println("1eat fish");
	}
	public void sport() {
		System.out.println("1can flow");
	}
	
}
class Dog extends Animal{
	//System.out.println("Hi, I am a Dog.");
	public void eat() {
		System.out.println("2eat beef");
	}
	public void sport() {
		System.out.println("2can run");
	}
}

https://blog.csdn.net/weixin_43206161