code: private static Browser parseBrowser(String userAgentString) {
  		for (Browser brower : Browser.browers) {
  			if (brower.isMatch(userAgentString)) {
  				return brower;
  			}
  		}
  		return Browser.Unknown;
  	}
docs: 解析浏览器类型
  
  @param userAgentString User-Agent字符串
  @return 浏览器类型