void (SliceRootNode oldRoot, SliceRootNode root) { SliceUsage rootUsage = oldRoot.getCachedChildren().get(0).getValue(); SliceManager.getInstance(Objects.requireNonNull(root.getProject())) .createToolWindow(true, root, true, SliceManager.getElementDescription(null, Objects.requireNonNull(rootUsage).getElement(), JavaBundle.message("tab.title.slices.grouped.by.nullness"))); }