工厂方法实施

Question

我正在浏览SO中的“工厂方法”页面并遇到了link。 并且this comment。该示例看起来像一个变体，并且考虑以其原始方式实现：将实例化推迟到子类...

这是我的尝试。以下代码是否实现了链接中指定的示例的Factory模式？请验证并建议是否必须进行任何重新分解。

public class ScheduleTypeFactoryImpl implements ScheduleTypeFactory {

    @Override
    public IScheduleItem createLinearScheduleItem() {
            return new LinearScheduleItem();
    }

    @Override
    public IScheduleItem createVODScheduleItem() {
     return new VODScheduleItem();
    }

}

public class UseScheduleTypeFactory {

    public enum ScheduleTypeEnum {
        CableOnDemandScheduleTypeID, 
            BroadbandScheduleTypeID, 
            LinearCableScheduleTypeID, 
            MobileLinearScheduleTypeID
    }

    public static IScheduleItem getScheduleItem(ScheduleTypeEnum scheduleType) {
        IScheduleItem scheduleItem = null;
        ScheduleTypeFactory scheduleTypeFactory = new ScheduleTypeFactoryImpl();
        switch (scheduleType) {
        case CableOnDemandScheduleTypeID:
            scheduleItem = scheduleTypeFactory.createVODScheduleItem();
            break;

        case BroadbandScheduleTypeID:
            scheduleItem = scheduleTypeFactory.createVODScheduleItem();
            break;

        case LinearCableScheduleTypeID:
            scheduleItem = scheduleTypeFactory.createLinearScheduleItem();
            break;

        case MobileLinearScheduleTypeID:
            scheduleItem = scheduleTypeFactory.createLinearScheduleItem();
            break;
        default:
            break;
        }
        return scheduleItem;
    }
}

Answer 1

我认为这是可以的，虽然我认为过于复杂。你真的不需要ScheduleTypeFactoryImpl课程。然后，您可以将UseScheduleTypeFactory课程更改为ScheduleTypeFactory。

我在想的是：

公共类ScheduleTypeFactory {

public enum ScheduleTypeEnum {
    CableOnDemandScheduleTypeID, 
        BroadbandScheduleTypeID, 
        LinearCableScheduleTypeID, 
        MobileLinearScheduleTypeID
}

public static IScheduleItem getScheduleItem(ScheduleTypeEnum scheduleType) {
    IScheduleItem scheduleItem = null;
    switch (scheduleType) {
    case CableOnDemandScheduleTypeID:
        scheduleItem = new VODScheduleItem();
        break;

    case BroadbandScheduleTypeID:
        scheduleItem = new VODScheduleItem();
        break;

    case LinearCableScheduleTypeID:
        scheduleItem = new LinearScheduleItem();
        break;
    case MobileLinearScheduleTypeID:
        scheduleItem = new LinearScheduleItem();
        break;
    default:
        break;
    }
    return scheduleItem;
}

}

您可能想要包含“默认”案例。