private static void addToLevel(final LogHierarchyNode tree, final LogEntry entry, final int left) {
    assert tree != null;
    if (left == 0) {
      tree.add(entry);
    } else {
      final List<LogHierarchyNode> children = tree.getChildren();
      assert ! children.isEmpty();
      addToLevel(children.get(children.size() - 1), entry, left - 1);
    }
  }
private static void addToLevel(final LogHierarchyNode tree, final LogEntry entry, final int left)