Java获取请求头信息的操作步骤

     RequestAttributes requestAttributes = RequestContextHolder.getRequestAttributes();//这个RequestContextHolder是Springmvc提供来获得请求的东西
        HttpServletRequest request = ((ServletRequestAttributes) requestAttributes).getRequest();
        HttpServletResponse response = ((ServletRequestAttributes) requestAttributes).getResponse();

 private   Map<String, Object>  getHeads(HttpServletRequest request){
        Map<String, Object> stringObjectHashMap = new HashMap<>();
        Enumeration<String> headers = request.getHeaderNames();
        System.out.println("请求头信息");
        while(headers.hasMoreElements()){
            String headName = (String)headers.nextElement();
            String headValue = request.getHeader(headName);
            System.out.println(headName+"："+headValue);
            stringObjectHashMap.put(headName,headValue);
        }
        return stringObjectHashMap;
    }

public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        // TODO Auto-generated method stub
        // place your code here
        HttpServletRequest  httpServletRequest = (HttpServletRequest) request;
        HttpServletResponse  httpServletResponse = (HttpServletResponse) response;
     	Enumeration<String> headerNames = httpServletRequest.getHeaderNames();
        while(headerNames.hasMoreElements()) {//判断是否还有下一个元素
            String nextElement = headerNames.nextElement();//获取headerNames集合中的请求头
            String header2 = httpServletRequest.getHeader(nextElement);//通过请求头得到请求内容
            System.err.println("请求头==========key" + nextElement + "----------VALUE:" + header2);
        }
   }