### Question:
App { public static void main(String[] args) { var root = new NodeImpl("1", new NodeImpl("11", new NodeImpl("111", NullNode.getInstance(), NullNode.getInstance()), NullNode.getInstance() ), new NodeImpl("12", NullNode.getInstance(), new NodeImpl("122", NullNode.getInstance(), NullNode.getInstance()) ) ); root.walk(); }  static void main(String[] args);  }### Answer:
@Test void shouldExecuteApplicationWithoutException() { assertDoesNotThrow(() -> App.main(new String[]{})); }