抽象方法和类

提示

• Abstract Methods and Classes

Abstract

abstract class GraphicObject {
    int x, y;
    // ...
    void moveTo(int newX, int newY) {
        // ...
    }
    abstract void draw();
    abstract void resize();
}

Subclass

class Circle extends GraphicObject {
    void draw() {
        // ...
    }
    void resize() {
        // ...
    }
}
class Rectangle extends GraphicObject {
    void draw() {
        // ...
    }
    void resize() {
        // ...
    }
}