如何重構與多個列表+ getter和setter一類爲每個列表

Question

我有下面的類：

public class RefactorMe { 

    private static List<Event<Apple>> mAppleEventList = new ArrayList<Event<Apple>>(); 
    private static List<Event<Banana>> mBananaEventList = new ArrayList<Event<Banana>>(); 
    private static List<Event<Orange>> mOrangeEventList = new ArrayList<Event<Orange>>(); 

    public static List<Event<Apple>> getAppleList() { 
    return mAppleEventList; 
    } 

    public static List<Event<Banana>> getBananaEventList() { 
    return mBananaEventList; 
    } 

    public static List<Event<Orange> getOrangeList() { 
    return mOrangeEventList; 
    } 

    public static void addAppleEvent(Event<Apple> pEvent) { 
    mAppleEventList.add(pEvent); 
    } 

    public static void addBananaEvent(Event<Banana> pEvent) { 
    mBananaEventList.add(pEvent); 
    } 

    public static void addOrangeEvent(Event<Orange> pEvent) { 
    mOrangeEventList.add(pEvent); 
    } 

} 

我嘗試使用Visitor模式重構，但不能得到它，因爲仿製藥的工作.. 有一個更好的方法嗎？

Answer 1

通過這裏使用的地圖繼@ user902383在Java 7中你的解決方案：

public class RefactorMe { 
    class Event<K> { 
    public K getNewObject() { 
     return null; 
    } 
    } 

    private static Map<Class<?>, List<Event<?>>> eventLists = new HashMap<>(); 

    public static <E> List<Event<E>> getEventList(Class<E> clazz) { 
    return (List) eventLists.get(clazz); 
    } 

    public static <E extends Event<E>> void addEvent(Event<E> pEvent) { 
    Class<E> key = (Class<E>) pEvent.getNewObject().getClass(); 
    List<Event<?>> events = eventLists.get(key); 
    if (events == null) { 
     events = new ArrayList<>(); 
     eventLists.put(key, events); 
    } 
    events.add(pEvent); 
    } 
}