twodcraft/src/main/java/cz/jzitnik/game/handlers/place/PlaceHandler.java

package cz.jzitnik.game.handlers.place;

import java.util.HashMap;
import java.util.Set;

import org.reflections.Reflections;

public class PlaceHandler {
    private final HashMap<String, CustomPlaceHandler> placeHandlerList = new HashMap<>();
    private final CustomPlaceHandler defaultPlaceHandler = new DefaultPlaceHandler();

    public boolean contains(String itemId) {
        return placeHandlerList.containsKey(itemId);
    }

    public CustomPlaceHandler get(String itemId) {
        if (!contains(itemId)) {
            return defaultPlaceHandler;
        }

        return placeHandlerList.get(itemId);
    }

    public PlaceHandler() {
        registerHandlers();
    }

    private void registerHandlers() {
        Reflections reflections = new Reflections("cz.jzitnik.game.handlers.place.handlers");
        Set<Class<?>> handlerClasses = reflections.getTypesAnnotatedWith(cz.jzitnik.game.annotations.PlaceHandler.class);

        for (Class<?> clazz : handlerClasses) {
            if (CustomPlaceHandler.class.isAssignableFrom(clazz)) {
                try {
                    CustomPlaceHandler handlerInstance = (CustomPlaceHandler) clazz.getDeclaredConstructor().newInstance();
                    cz.jzitnik.game.annotations.PlaceHandler annotation = clazz.getAnnotation(cz.jzitnik.game.annotations.PlaceHandler.class);
                    placeHandlerList.put(annotation.value(), handlerInstance);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        }
    }
}