代碼如下:

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; 
    } 
} 

復制代碼代碼如下:

package Object.reference; 
/*  java 中的值傳遞和引用傳遞 
    //www.jfrwli.cn/
    java 中沒有引用傳遞，都是值傳遞的 
*/
public class Test { 
    public static void swap(People a, People b, boolean flag) { 
        if (flag) { 
            // 可以通過傳遞副本修改對象的值 
            a.setName("changeName"); 
            a.setAge(100); 
        } else { 
            //副本交換，并不影響主程序的指針 
            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);//傳遞的是p1,p2的副本，函數調用前后p1,p2沒任何改變 
        swap(p1, p2,true);//傳遞的是p1,p2的副本，可以通過傳遞副本修改對象的值,函數調用前后p1對象內容改變 
    } 
}