toString的用法

toString方法是一个非常特殊的方法，它是一个“自我描述”

class Apple
{
	private String color;
	private double weight;
	public Apple(String color,double weight){
		this.color=color;
		this.weight=weight;
	}
	public String toString(){
		return "一个苹果，颜色是："+color+",重量是："+weight;
	}
}
public class TestToString 
{

	public static void main(String[] args) {

		Apple a=new Apple("red",12);
		System.out.println(a);
	}
}