class point
{
    int x,y;
    void setXY(int m,int n)
    {
        x=m;
        y=n;
    }
}
public class application4_8
{
    public static void main(String args[])
    {
                 point  p1,p2,p3;
                p1=new point();
        p2=new point();
        System.out.println("p1的引用:"+p1);
        System.out.println("p2的引用:"+p2);
        p1.setXY(1111,2222);
        p2.setXY(-100,-200);
        System.out.println("p1的x,y坐标:"+p1.x+"."+p1.y);
        System.out.println("p2的x,y坐标:"+p2.x+"."+p2.y);
        p2=p1;
        System.out.println("p1的x,y坐标:"+p1.x+"."+p1.y);
        System.out.println("p2的x,y坐标:"+p2.x+"."+p2.y);
        p3=p2;
        p3.x=10;
        p3.y=60;
        System.out.println("p1的x,y坐标:"+p1.x+"."+p1.y);
    }
}

为什么最后p1的坐标是10，60，按道理说p2赋值给p3，应该用p2的值代替P3，则p1的坐标应该不变啊，怎么会变成10，60，不懂，请大神指教！！

package thread_437143;

class Point {
    int x, y;

    void setXY(int m, int n) {
        x = m;
        y = n;
    }
}

public class Application4_8 {
    public static void main(String args[]) {
        Point p1, p2, p3;
        p1 = new Point();
        p2 = new Point();
        System.out.println("p1的引用:" + p1);
        System.out.println("p2的引用:" + p2);
        p1.setXY(1111, 2222);
        p2.setXY(-100, -200);
        System.out.println("p1的x,y坐标:" + p1.x + "." + p1.y);
        System.out.println("p2的x,y坐标:" + p2.x + "." + p2.y);
        p2 = p1;
        System.out.println("p1的x,y坐标:" + p1.x + "." + p1.y);
        System.out.println("p2的x,y坐标:" + p2.x + "." + p2.y);
        p3 = p2;
        p3.x = 10;
        p3.y = 60;
        System.out.println("p1的x,y坐标:" + p1.x + "." + p1.y);
        System.out.println("p1的引用:" + p1);
        System.out.println("p2的引用:" + p2);
        System.out.println("p3的引用:" + p3);
    }
}

执行完下面这些语句之后，p2指向p1，p3指向p2，所以结果没有什么不可思议的
p2 = p1;
p3 = p2;

你都知道这是对象引用咯，为什么还会说不可思议，只有你没了解什么是对象引用。

我可能弄反了，

p2 = p1;这样的语句在Fortran或者早期的Basic语言里，
写成【let p2 = p1;】

读作让p2等于p1，或者让p2指向p1
前面加个let并读作【让】，就不会理解反了

已受教，留名顶贴