Java设计模式之策略模式解析

/**
 * @author gf
 * @date 2023/2/7
 */
@Getter
@AllArgsConstructor
public enum ActivityTypeEnum {
 
    MANJIAN(101, "满减活动"),
    MANZHE(102, "满折活动"),
    PRESALE(103, "预售活动");
 
    int type;
 
    String desc;
 
}

/**
 * @author gf
 * @date 2023/2/7
 */
public interface ActivityService {
 
    /**
     * 创建活动
     *
     * @return
     */
    void createActivity();
 
    /**
     * 获取订单类型
     *
     * @return
     */
    ActivityTypeEnum type();
 
}

/**
 * @author gf
 * @date 2023/2/7
 */
@Slf4j
@Service
public class ManJianActivityImpl implements ActivityService {
    @Override
    public void createActivity() {
        log.info("----创建满减活动----");
    }
 
    @Override
    public ActivityTypeEnum type() {
        return ActivityTypeEnum.MANJIAN;
    }
}

/**
 * @author gf
 * @date 2023/2/7
 */
@Slf4j
@Service
public class ManZheActivityImpl implements ActivityService {
    @Override
    public void createActivity() {
        log.info("----创建满折活动----");
    }
 
    @Override
    public ActivityTypeEnum type() {
        return ActivityTypeEnum.MANZHE;
    }
}

/**
 * @author gf
 * @date 2023/2/7
 */
@Slf4j
@Service
public class PreSaleActivityImpl implements ActivityService {
 
    @Override
    public void createActivity() {
        log.info("----创建预售活动----");
    }
 
    @Override
    public ActivityTypeEnum type() {
        return ActivityTypeEnum.PRESALE;
    }
}

/**
 * @author gf
 * @date 2023/2/7
 */
@RestController
public class ActivityController {
 
 
    @Autowired
    private List<ActivityService> activityService;
 
    /**
     * 创建活动
     *
     * @param type 活动类型
     * @return
     */
    public void createActivity(int type) {
        /**
         * 根据动类型，找到对应的处理器
         */
        Optional<ActivityService> any = activityService.stream().filter(f -> f.type().getType() == type).findAny();
        /**
         * 没有对应的处理器
         */
        if (!any.isPresent()) {
            throw new RuntimeException("没有找到相应的活动实现");
        }
        // 创建订单
        any.get().createActivity();
    }
 
}

@SpringBootTest
class DesignApplicationTests {
 
 
    @Autowired
    private ActivityController activityController;
 
    @Test
    void contextLoads() {
        activityController.createActivity(ActivityTypeEnum.MANJIAN.getType());
        
    }
 
}