code: public static String format(String s, Map<String, String> map) {
  		StringBuilder sb = new StringBuilder((int)(s.length() * 1.5));
  		int cursor = 0;
  		for (int start, end; (start = s.indexOf("${", cursor)) != -1 && (end = s.indexOf('}', start)) != -1;) {
  			sb.append(s.substring(cursor, start));
  			String key = s.substring(start + 2, end);
  			sb.append(map.get(StringUtils.trim(key)));
  			cursor = end + 1;
  		}
  		sb.append(s.substring(cursor, s.length()));
  		return sb.toString();
  	}
docs: 将字符串中特定模式的字符转换成map中对应的值
  
  use: format("my name is ${name}, and i like ${like}!", {"name":"L.cm", "like": "Java"})
  
  @param s		需要转换的字符串
  @param map	转换所需的键值对集合
  @return		{String}转换后的字符串