Question

我有一个类，它有几个代表不同类型设备名称的枚举。

public class DeviceNames {
    public enum Microsoft {
        DeviceName1, DeviceName2, DeviceName3
    }

    public enum Apple {
        DeviceName1, DeviceName2, DeviceName3
    }
}

我有不同具体设备将实现的接口（接口指定它可以通信的方式）

public interface IPDevice{
    //factory method
    Device createNewIPDevice(DeviceNames.Enum<E> deviceName);
}

public interface USBDevice{
    //factory method
    Device createNewUSBDevice(DeviceNames.Enum<E> deviceName);
}

我有一个抽象类

public abstract class Device {
    String deviceName;

    protected Device(String deviceName) {
        this.deviceName = deviceName;
    }
}

实现一个或多个接口的抽象类的具体实现

public class MicrosoftDevice implements IPDevice{
    @Override
    public Device createNewIPDevice(DeviceNames.Microsoft deviceName) {
        return super(deviceName.toString());
    }
}

public class AppleDevice implements IPDevice, USBDevice {
    @Override
    public Device createNewIPDevice(DeviceNames.Apple deviceName) {
        return super(deviceName.toString());
    }

    @Override
    public Device createNewUSBDevice(DeviceNames.Apple deviceName) {
        return super(deviceName.toString();
    }
}

我想使用枚举来确保它们只提供有效的设备名称（而不是传递给字符串）

如何让接口方法采用一个可以采用通用枚举类型但只包含DeviceNames类中的枚举的参数？

Answer 1

我问了一个跟进问题here。接受的答案解决了这个问题。

引用@Andreas（回答另一个问题的人）

您使接口本身实际上采用通用参数

工作代码如下所示（此处未包含的代码保持不变）：

public interface IPDevice<DeviceName extends Enum> {
    //factory method
    Device createNewIPDevice(DeviceName deviceName);
}

public interface USBDevice<DeviceName extends Enum> {
    //factory method
    Device createNewUSBDevice(DeviceName deviceName);
}

public class MicrosoftDevice implements IPDevice<DeviceNames.Microsoft> {
    @Override
    public Device createNewIPDevice(DeviceNames.Microsoft deviceName) {
        return super(deviceName.toString());
    }
}

public class AppleDevice implements IPDevice<DeviceNames.Apple>, USBDevice<DeviceNames.Apple> {
    @Override
    public Device createNewIPDevice(DeviceNames.Apple deviceName) {
        return super(deviceName.toString());
    }

    @Override
    public Device createNewUSBDevice(DeviceNames.Apple deviceName) {
        return super(deviceName.toString();
    }
}

如何让一个参数成为类中几种枚举类型之一

1 个答案: