public void testClear() {
    LayerGroupInfoImpl lg = mockGroup("tesGroup", mockLayer("L1"), mockLayer("L2"));

    assertNull(LegacyTileLayerInfoLoader.load(lg));
    GeoServerTileLayerInfo info = defaultVectorInfo;
    info.getMimeFormats().clear();
    info.getMimeFormats().addAll(defaults.getDefaultOtherCacheFormats());

    LegacyTileLayerInfoLoader.save(info, lg.getMetadata());

    GeoServerTileLayerInfo actual;
    actual = LegacyTileLayerInfoLoader.load(lg);
    assertNotNull(actual);

    LegacyTileLayerInfoLoader.clear(lg.getMetadata());
    assertNull(LegacyTileLayerInfoLoader.load(lg));
  }