code: public static String getHeader(HttpServletRequest request, String header) {
  
  		// noting to search in or nothing to be found
  		if (request == null || StringUtils.isNullOrEmptyTrimmed(header)) {
  			return null;
  		}
  
  		return request.getHeader(header);
  	}
docs: Returns header from given request
  
  @param request to search for header
  @param header  name
  @return header value or null if not found