Question

我想为我的泛型类创建一个工厂。我有Device基类：

public abstract class Device<T> {

T stateVariable;
private String name;

public Device(T stateVariable, String name) {
    super();
    this.name = name;
    this.stateVariable = stateVariable;
}

// getters & setters 


abstract void changeActualState(T changeVariable);

}

TV类扩展了设备：

public class TV<T> extends Device<T>{


public TV(T stateVariable, String name) {
    super(stateVariable, name);
}

@Override
void changeActualState(T changeVariable) {
    if(!changeVariable.equals(stateVariable)){
        System.out.println("The TV now is " + changeVariable);
        setStateVariable(changeVariable);
    }
}
}

还有Therme类，它也扩展了Device类：

public class Therme<T> extends Device<T> {

public Therme(T stateVariable, String name) {
    super(stateVariable, name);
}

@Override
void changeActualState(T changeVariable) {
    if(!changeVariable.equals(stateVariable)){
        System.out.println("The temperature changed to " + changeVariable);
        setStateVariable(changeVariable);
    }
}
}

我也有一个枚举：

enum Type{
    TV, Therme
}

我想创建一个工厂，取决于enum的类型来制作特定的类。

Answer 1

实现这一目标有很多选择。这是将设备直接嵌入枚举中的一个：

enum Type {
    TV {
        @Override
        protected <T> BiFunction<T, String, Device<T>> deviceCreator() {
            return device.TV::new;
        }
    },
    Therme {
        @Override
        protected <T> BiFunction<T, String, Device<T>> deviceCreator() {
            return device.Therme::new;
        }
    };

    protected abstract <T> BiFunction<T, String, Device<T>> deviceCreator();

    public <T> Device<T> createDevice(T stateVariable, String name) {
        return this.<T>deviceCreator().apply(stateVariable, name);
    }
}

在java中为泛型创建工厂

1 个答案: