Java中的值传递和引用传递实例介绍_java

复制代码 代码如下:

package Object.reference;
public class People {
    private String name;
    private int age;
    public People(){
    }
    public People(String name, int age) {
        super();
        this.name = name;
        this.age = age;
    }
    public String toString(){
        return "name:" + name + " age:" + age;
    }
    public String getName() {
        return name;
    }
    public int getAge() {
        return age;
    }
    public void setName(String name) {
        this.name = name;
    }
    public void setAge(int age) {
        this.age = age;
    }
}

复制代码 代码如下:

package Object.reference;
/*  java 中的值传递和引用传递
    http://www.jb51.net/clara/archive/2011/09/17/2179493.html
    java 中没有引用传递，都是值传递的
*/
public class Test {
    public static void swap(People a, People b, boolean flag) {
        if (flag) {
            // 可以通过传递副本修改对象的值
            a.setName("changeName");
            a.setAge(100);
        } else {
            //副本交换，并不影响主程序的指针
            People c = a;
            a = b;
            b = c;
        }
    }
    public static void main(String[] args) {
        People p1 = new People("yingjie", 23);
        People p2 = new People("yuexin", 20);
        swap(p1, p2,false);//传递的是p1,p2的副本，函数调用前后p1,p2没任何改变
        swap(p1, p2,true);//传递的是p1,p2的副本，可以通过传递副本修改对象的值,函数调用前后p1对象内容改变
    }
}