基础：c++中引用与java中的引用

using namespace std;
 class Point
{
    public:
        double x;
        double y;
        Point(){}
        void setPoint(double x,double y )
        {
            this->x = x;
            this->y = y;
        }
    Point(double xx,double yy)
        {
            this->x=xx;
            this->y=yy;
        }
};
class Point1
{
    public:
        Point point;
    void set()
    {
        point.x=1;
        point.y=2;
        cout<<point.x<<point.y<<endl;
    }
};

class Point2
{
    public:
        Point point;
    void set(Point point)
    {
        point.x=1;
        point.y=2;
        cout<<point.x<<point.y<<endl;
    }
};
class Point3
{
    public:
        Point point;
    void set(Point &point)
    {
        point.x=1;
        point.y=2;
        cout<<point.x<<point.y<<endl;
    }
};

int main(int argc,char *argv[])
{
    Point1 point1;
    point1.set();
    cout<<point1.point.x<<point1.point.y<<endl;
    Point2 point2;
    point2.set(point2.point);
    cout<<point2.point.x<<point2.point.y<<endl;
    Point3 point3;
    point3.set(point3.point);
    cout<<point3.point.x<<point3.point.y<<endl;
    return 0;
}

c++中要想让内部操作印象到外部，需要使用引用或者指针。

java中将摒弃指针，全部使用引用进行操作。