Java判断浏览器是微信还是支付宝

@RequestMapping("getBrowser.do") 
public String getBrowser(HttpServletRequest req, HttpServletResponse resp) { 
  String userAgent = req.getHeader("user-agent"); 
  if (userAgent != null && userAgent.contains("AlipayClient")) { 
    return "来自支付宝"; 
  }else if (userAgent != null && userAgent.contains("MicroMessenger")) { 
    return "来自微信"; 
  }else{ 
    return "未知来源"; 
  } 
} 

//判断是支付宝app的浏览器
 var userAgent = navigator.userAgent.toLowerCase();

  if(userAgent.match(/Alipay/i)=="alipay"){
    return true;
  }else{
    return false;
  }

//判断是微信app的浏览器
function isWechat(){
  var userAgent = navigator.userAgent.toLowerCase();
  if(userAgent.match(/MicroMessenger/i)=="micromessenger") {
    return true;
  } else {
    return false;
  }
}