Java工具：剔除以，逗號分隔的重複字符的字符串

public static Set<String> dealRepeat(String str) {
		String[] split = str.split(",");
		Map<String,String> map=new HashMap<String,String>();
		for (String string : split) {
			map.put(string, string);
		}
		Set<String> keySet = map.keySet();
		return keySet;
	}