设计模式-工厂方法模式（三）

public class SquareFactory implements ShapeFactory {
    private double side;

    public SquareFactory(double side) {
        this.side = side;
    }

    @Override
    public Shape createShape() {
        return new Square(side);
    }
}

public class RectangleFactory implements ShapeFactory {
    private double width;
    private double height;

    public RectangleFactory(double width, double height) {
        this.width = width;
        this.height = height;
    }

    @Override
    public Shape createShape() {
        return new Rectangle(width, height);
    }
}

public class Client {
    public static void main(String[] args) {
        // 创建具体工厂类的对象
        ShapeFactory circleFactory = new CircleFactory(5);
        ShapeFactory squareFactory = new SquareFactory(4);
        ShapeFactory rectangleFactory = new RectangleFactory(3, 4);

        // 调用工厂方法创建具体产品类的对象
        Shape circle = circleFactory.createShape();
        Shape square = squareFactory.createShape();
        Shape rectangle = rectangleFactory.createShape();

        // 使用具体产品类的对象
        System.out.println("Circle perimeter: " + circle.calculatePerimeter());
        System.out.println("Circle area: " + circle.calculateArea());
        System.out.println("Square perimeter: " + square.calculatePerimeter());
        System.out.println("Square area: " + square.calculateArea());
        System.out.println("Rectangle perimeter: " + rectangle.calculatePerimeter());
        System.out.println("Rectangle area: " + rectangle.calculateArea());
    }
}

Circle perimeter: 31.41592653589793
Circle area: 78.53981633974483
Square perimeter: 16.0
Square area: 16.0
Rectangle perimeter: 14.0
Rectangle area: 12.0