设计模式（2）工厂模式

让一个工厂类去生产出对象 （new ）来。

我们想要一个 形状，我们用工厂去生产出，圆形，方形。

package com.example.factory2;

public interface Shape {
    void draw();
}

public class Square implements Shape {
    @Override
    public void draw() {
        Log.d("LIU", "this is Square");
    }
}

public class Circle implements Shape {
    @Override
    public void draw() {
        Log.d("LIU","this is circle");
    }
}

factory class:

public class ShapeFactory {
    public Shape getShape (int type) {
        if (type == 1) {
            return new Circle();
        } else if (type ==2) {
            return  new Square();
        } else {
            return null;
        }

    }
}

example and output:

        ShapeFactory shapeFactory = new ShapeFactory();
        Shape shape = shapeFactory.getShape(1);
        shape.draw();
        Shape shape2 = shapeFactory.getShape(2);
        shape2.draw();



2024-10-02 22:23:47.705 14673-14673/com.example.factory2 D/LIU: this is circle
2024-10-02 22:23:47.706 14673-14673/com.example.factory2 D/LIU: this is Square

参考： 工厂模式 | 菜鸟教程