Filter example

@Component
public class MDCFilter extends OncePerRequestFilter {

    @Override
    protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain)
            throws ServletException, IOException {
        MDC.put("tracking", request.getHeader("tracking-header"));
        try {
            filterChain.doFilter(request, response);
        } finally {
            MDC.clear();
        }
    }
}