public static int[] getGcIdsForSize(final CacheSize size) {
        if (size.gcIds != null) {
            return size.gcIds;
        }
        //special cases:
        switch (size) {
            case NANO:
                return MICRO.gcIds;
            case VERY_LARGE:
                return LARGE.gcIds;
            case NOT_CHOSEN:
                return OTHER.gcIds;
            default:
                return new int[0];
        }
    }
lookup for OC JSON requests (the numeric size is deprecated for OC)
main/src/main/java/cgeo/geocaching/enumerations/CacheSize.java