传引用

测试程序，引用

public class Demo {
	public static void main(String[] args) {
		DemoPro pro = new DemoPro(20, "lishan");
		System.out.println("Before change, pro = " + pro.getAge());
		changeData(pro);
		System.out.println("After changeData(n), pro = " + pro.getAge());
	}

	public static void changeData(DemoPro pro) {
		pro = new DemoPro(26, "liudehua");

		System.out.println(pro.getAge());
	}
}

输出结果：

Before change, pro = 20
26
After changeData(n), pro = 20

[color=red][/color]



如果代码如下：

public class Demo {
	public static void main(String[] args) {
		DemoPro pro = new DemoPro(20, "lishan");
		System.out.println("Before change, pro = " + pro.getAge());
		changeData(pro);
		System.out.println("After changeData(n), pro = " + pro.getAge());
	}

	public static void changeData(DemoPro pro) {
		//pro = new DemoPro(26, "liudehua");
		pro.setAge(26) ;
		System.out.println(pro.getAge());
	}
}

输出结果：

Before change, pro = 20
26
After changeData(n), pro = 26

评论

1 楼 zczh3 2011-03-23  

N多年前 已经很多人讨论N遍：
JAVA 与 C 只存在 传值，Java 不存在传引用，C不存在传地址
只有C++ 支持传引用 与 传值