工厂类

/**
 * @Author: chuan.bai
 * @Description 支付工厂
 * @Date: Created on 10:58 2021/3/25
 * @Modified By:
 */
public interface PayFactory {

    void submitOrder();

    void refundOrder();
    void cancelOrder();
}

paypal实现

/**
 * @Author: chuan.bai
 * @Description  paypal 支付工厂
 * @Date: Created on 11:00 2021/3/25
 * @Modified By:
 */
public class PayPalFactory implements PayFactory{
    @Override
    public void submitOrder() {
        System.out.println("PayPalFactory.submitOrder");
    }

    @Override
    public void refundOrder() {
        System.out.println("PayPalFactory.refundOrder");
    }

    @Override
    public void cancelOrder() {
        System.out.println("PayPalFactory.cancelOrder");
    }
}

amazon实现

/**
 * @Author: chuan.bai
 * @Description amazon 支付工厂
 * @Date: Created on 11:01 2021/3/25
 * @Modified By:
 */
public class AmazonPayFactory implements PayFactory{
    @Override
    public void submitOrder() {
        System.out.println("AmazonPayFactory.submitOrder");
    }

    @Override
    public void refundOrder() {
        System.out.println("AmazonPayFactory.refundOrder");
    }

    @Override
    public void cancelOrder() {
        System.out.println("AmazonPayFactory.cancelOrder");
    }
}

adyen实现

/**
 * @Author: chuan.bai
 * @Description adyen支付工厂
 * @Date: Created on 11:02 2021/3/25
 * @Modified By:
 */
public class AdyenPayFactory implements PayFactory{
    @Override
    public void submitOrder() {
        System.out.println("AdyenPayFactory.submitOrder");
    }

    @Override
    public void refundOrder() {
        System.out.println("AdyenPayFactory.refundOrder");
    }

    @Override
    public void cancelOrder() {
        System.out.println("AdyenPayFactory.cancelOrder");
    }
}

/**
 * @Author: chuan.bai
 * @Description 操作客户端
 * @Date: Created on 11:03 2021/3/25
 * @Modified By:
 */
public class PayClient {
    private static List<String > paymethodList =new ArrayList<>();

    static {
        paymethodList.add("paypal");
        paymethodList.add("amazon");
        paymethodList.add("adyen");
    }

    public static void main(String[] args) {
        //默认为paypal 支付
        PayFactory payFactory = new PayPalFactory();
        for (String paymethod : paymethodList) {
            System.out.println("开始使用"+paymethod+"支付");
            switch (paymethod){
                case "adyen":
                    payFactory = new AdyenPayFactory();
                    break;
                case "amazon":
                    payFactory = new AmazonPayFactory();
                    break;
                case "paypal":
                    payFactory = new PayPalFactory();
                    break;
                default:
                    payFactory = new PayPalFactory();
                    break;
            }
            //调用支付的 提交订单，取消订单，退款的方法
            payFactory.submitOrder();
            payFactory.cancelOrder();
            payFactory.refundOrder();
        }

    }
}

输出结果

开始使用paypal支付
PayPalFactory.submitOrder
PayPalFactory.cancelOrder
PayPalFactory.refundOrder
开始使用amazon支付
AmazonPayFactory.submitOrder
AmazonPayFactory.cancelOrder
AmazonPayFactory.refundOrder
开始使用adyen支付
AdyenPayFactory.submitOrder
AdyenPayFactory.cancelOrder
AdyenPayFactory.refundOrder

Process finished with exit code 0