Java多态子类函数调用

问题描述

我非常确定我可以在Stackoverflow上找到此问题的答案。不幸的是，我不知道这样做的具体方式。

鉴于以下代码，我有一个问题，我想避免类型检查。这些评论可能比我的话更好地描述它。

现在，我正在尝试建立一个形状系统，其中每个形状都可以与每个可能的特定形状碰撞。 CollisionClass：

public class ShapeCollision {
    public static boolean intersects(RectShape rectShape1,RectShape rectShape2) { return true; }

    public static boolean intersects(Lineshape lineshape,RectShape rectShape) { return true; }

    public static boolean intersects(RectShape rectShape1,Shape shape) { return true; }

    public static boolean intersects(Lineshape lineshape,Shape shape) { return true; }

    public static boolean intersects(Shape shape1,Shape shape2){ return true; }
}

ShapeClasses：

public class RectShape extends Shape {
    Vector size;
    public RectShape(Vector pos,Vector size) {
        super(pos);
        this.size = size;
    }
    @Override
    public boolean intersects(IShape shape) {
        return ShapeCollision.intersects(this,shape);
    }
}

public class Lineshape extends Shape {
    Vector pos2;
    public Lineshape(Vector pos,Vector pos2) {
        super(pos);
        this.pos2 = pos2;
    }
    @Override
    public boolean intersects(IShape shape) {
        return ShapeCollision.intersects(this,shape);
    }
}

public class Shape implements IShape {
    protected Vector pos;
    public Shape(Vector pos) {
        this.pos = pos;
    }
    @Override
    public Vector getPos() {
        return pos;
    }
    @Override
    public void setPos(Vector pos) {
        this.pos = pos;
    }
    @Override
    public void move(Vector movementAmount) {
        pos.add(movementAmount);
    }
    @Override
    public boolean intersects(IShape shape) {
        return ShapeCollision.intersects(this,shape);
    }
}

这对我来说是令人困惑的部分：

Shape rect = new RectShape(new Vector(0,0),new Vector(20,20));
Shape rect2 = new RectShape(new Vector(0,20));
Shape line = new Lineshape(new Vector(0,20));

//Since I am saving shape and no specific shapetype,it will pass shape and pick the specific superFunction 
//Right Now it calls the intersects(RectShape rectShape1,Shape shape) function due to calling it through the shape variable
rect.intersects(rect2); 
//This calls the intersects(Lineshape lineshape,Shape shape) function
rect.intersects(line);    
//This calls the intersects(Shape shape1,Shape shape2) function
ShapeCollision.intersects(rect,line);

如何在不指定变量类型的情况下实现它，即调用带有子类参数的“正确”函数。（例如：（Lineshape lineshape，RectShape rectShape））

我不想在这些函数中进行任何类型检查并专门调用这些函数，而是尽可能使用一些DesignPatters或类似的东西：）

解决方法

如果不对函数内部进行类型检查或在将Shape实例传递给函数调用之前对Shape实例进行一些显式转换，就无法实现所需的结果。

您当然可以使用特定的类声明对象引用，但是我想这并没有帮助。

java java polymorphism subclass