demo.java~5~

提供了常用的JAVA技术的示例

// 5-22 如何运用抽象类。

package Demo;

abstract class Shape{
    int position_x,position_y; // 坐标 变量
    void MoveTo(int new_pos_x,int new_pos_y){
        position_x=new_pos_x;
        position_y=new_pos_y;
    }
    abstract void draw(); // 抽象方法
}


class Square extends Shape{
    int length;
    void draw(){
        System.out.println("this is a square.");
    }
}


class  Circle extends Shape{
    int radius;
    void draw(){
        System.out.println("this is a circle.");
    }
}


class Trigon extends Shape{
    int bottom;
    //int highness;
    void show(){
        System.out.println("this is a trigon.");
    }
}


class ShapeManager{
    void manager(Shape obj){
        obj.draw();
    }
}


public class Demo {
    public static void main(String args[]){
        ShapeManager shape_man=new ShapeManager();
        Square sq=new Square();
        Circle ci=new Circle();
        Trigon tr=new Trigon();
        shape_man.manager(sq);
        shape_man.manager(ci);
        shape_man.manager(tr);
    }
}