定义一系列的算法,把它们一个个封装起来, 并且使它们可相互替换。

策略抽象

/**
 * @Author: chuan.bai
 * @Description  策略抽象
 * @Date: Created on 17:25 2021/3/24
 * @Modified By:
 */
public interface PayStrategy {
   void doPay(PayOrderRequest request);
}

提交支付单策略

/**
 * @Author: chuan.bai
 * @Description 提交支付单的策略
 * @Date: Created on 17:46 2021/3/24
 * @Modified By:
 */
public class SubmitOrderStrategy implements PayStrategy{


    @Override
    public void doPay(PayOrderRequest request) {
        System.out.println("执行提交支付单操作");

    }
}

查询支付单的策略

/**
 * @Author: chuan.bai
 * @Description 查询支付单的策略
 * @Date: Created on 17:46 2021/3/24
 * @Modified By:
 */
public class QueryPayStrategy implements PayStrategy {


    @Override
    public void doPay(PayOrderRequest request) {
        System.out.println("执行查询支付单操作");
    }
}

取消支付的策略

/**
 * @Author: chuan.bai
 * @Description 取消支付的策略
 * @Date: Created on 17:53 2021/3/24
 * @Modified By:
 */
public class CancelOrderStrategy implements PayStrategy{
    @Override
    public void doPay(PayOrderRequest request) {
        System.out.println("执行取消支付单操作");
    }
}

支付策略上下文

/**
 * @Author: chuan.bai
 * @Description  支付策略上下文
 * @Date: Created on 17:50 2021/3/24
 * @Modified By:
 */
public class PayContext {
    private PayStrategy payStrategy;


    public PayContext(PayStrategy payStrategy) {
        this.payStrategy = payStrategy;
    }

    public void executePay(PayOrderRequest request){
        payStrategy.doPay(request);
    }
}

顾客操作类

/**
 * @Author: chuan.bai
 * @Description  顾客
 * @Date: Created on 17:56 2021/3/24
 * @Modified By:
 */
public class Customer {


    public static void main(String[] args) {
        //取消支付单
        PayOrderRequest payOrderRequest = new PayOrderRequest();
        PayContext payContext = new PayContext(new SubmitOrderStrategy());
        payContext.executePay(payOrderRequest);

        //取消支付单
        payContext = new PayContext(new CancelOrderStrategy());
        payContext.executePay(payOrderRequest);
    }
}