java例程练习(对象转型及instanceof关键字)

public class Test {
	public static void main(String[] args) {
		Animal a = new Animal("name");
		Cat c = new Cat("Tom", "Blue");
		Dog d = new Dog("Pipi", "Black");
		
		System.out.println(a instanceof Animal);
		System.out.println(c instanceof Animal);
		System.out.println(d instanceof Animal);
		System.out.println(a instanceof Cat);
		System.out.println();
		
		a = new Dog("Bangbang", "Yellow");
		System.out.println(a instanceof Animal);
		System.out.println(a instanceof Dog);
		System.out.println();
		
		Dog d1 = (Dog)a;
		System.out.println(d1 instanceof Animal);
		System.out.println(d1 instanceof Dog);
		System.out.println();
		
		Test test = new Test();
		test.info(a);
		test.info(c);
		test.info(d);
		test.info(d1);
	}
	
	public void info(Animal	a) {
		System.out.print("" + a.name);
		if(a instanceof Cat) {
			Cat cat = (Cat)a;
			System.out.print(" has " + cat.eyeColor + " eyes");
		} else if(a instanceof Dog) {
			Dog dog = (Dog)a;
			System.out.print(" has " + dog.furColor + " fur");
		}
		System.out.println();
	}

}

class Animal {
	public String name;
	Animal(String name) {
		this.name = name;
	}
}

class Cat extends Animal {
	public String eyeColor;
	Cat(String n, String c) {
		super(n);
		eyeColor = c;
	}
}

class Dog extends Animal {
	public String furColor;
	Dog(String n, String c) {
		super(n);
		furColor = c;
	}
}

posted on 2012-04-22 14:07  Yours风之恋  阅读(166)  评论(0编辑  收藏  举报