@Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
      throws IOException, ServletException {
      if (filterConfig == null) {
        return;
      }

      String uri = ((HttpServletRequest) request).getRequestURI();
      LOG.info("filtering " + uri);
      RECORDS.add(uri);
      chain.doFilter(request, response);
    }
A very simple filter that records accessed uri's
hbase-http/src/test/java/org/apache/hadoop/hbase/http/TestGlobalFilter.java