public String convert(ILoggingEvent le) {
    List<Marker> markers = le.getMarkers();
    if (markers == null || markers.isEmpty()) {
      return EMPTY;
    } else {
      return markers.toString();
    }
  }
@Test
  public void testWithMarker() {
    String name = "test";
    Marker marker = markerFactory.getMarker(name);
    String result = converter.convert(createLoggingEvent(marker));
    assertEquals("[" + name + "]", result);
  }