duck.java

Java面向对象编程(随书配套源代码) 阐述了面向对象编程的思想

package chapter7;

public class Duck extends Animal 
{
	public Duck()
	{
		super("鸭子");
	}
	public  void eat(String food)
	{
		System.out.print("我是一只鸭子,");
		if(!food.equals("饲料"))
		{
		   System.out.println("我要吃饲料");
		}
		else
		{
			super.eat(food);
		}
	}
	public void layEgg()
	{
		System.out.println("我是鸭子，我下了一个蛋");
	}
}