public void testChildrenNames() throws Exception { Preferences subnode = pref.node("c1"); subnode.put("k", "v"); subnode.flush(); subnode = pref.node("c2"); subnode.put("k", "v"); subnode.flush(); subnode = pref.node("c3/c4"); subnode.put("k", "v"); subnode.flush(); assertEquals( new TreeSet<String>(Arrays.asList("c1", "c2", "c3")), new TreeSet<String>(Arrays.asList(storage.childrenNames()))); pref.node("c2").removeNode(); assertEquals( new TreeSet<String>(Arrays.asList("c1", "c3")), new TreeSet<String>(Arrays.asList(storage.childrenNames()))); pref.node("c3").removeNode(); assertEquals( Collections.singleton("c1"), new TreeSet<String>(Arrays.asList(storage.childrenNames()))); pref.node("c1").removeNode(); assertEquals( Collections.emptySet(), new TreeSet<String>(Arrays.asList(storage.childrenNames()))); }