Method sortMapByKey

src/custom/CMapSort.java:11–26

ʹ�� Map��key�������� @param map @return

(Map<String, String> map, String sortMethod)

	 * @return
	 */
	public static Map<String, String> sortMapByKey(Map<String, String> map, String sortMethod) {
		if (map == null || map.isEmpty()) {
			return null;
		}
		if (sortMethod.equals("ASCENDING")){
			Map<String, String> sortMap = new TreeMap<String, String>(new MapKeyComparator());
			sortMap.putAll(map);
			return sortMap;
		}else if (sortMethod.equals("DESCENDING")) {
			Map<String, String> sortMap = new TreeMap<String, String>(new MapKeyComparatorDesc());
			sortMap.putAll(map);
			return sortMap;
		}else {
			return null;
		}
	}
	
	/**
	 * ʹ�� Map��value��������