code: public static String line2Hump(String str) {
          str = str.toLowerCase();
          Matcher matcher = linePattern.matcher(str);
          StringBuffer sb = new StringBuffer();
          while (matcher.find()) {
              matcher.appendReplacement(sb, matcher.group(1).toUpperCase());
          }
          matcher.appendTail(sb);
          return upperFirst(sb.toString());
      }
docs: 蛇形转驼峰
  
  @param str
  待转换字符串
  @return 转换结果