java基础入门-对象与对象变量

package com.ray.object;

/**
 * 对象与对象变量
 * 
 * @author ray
 * @since 2015-04-22
 * @version 1.0
 * 
 */
public class Person {
	
	public Person (){}
	
	public static void main(String[] args) {
		Person bill = new Person();
		Person jack;
		System.out.println(bill.toString());
		//下面这里直接报错，对象变量没有实例出真实的对象出来
		System.out.println(jack.toString());
	}
}