1. google guava工具类
List<String> list2 = Lists.newArrayList("3", "4");
2. Arrays.asList
List<String> linkedList = new LinkedList<>(Arrays.asList("3", "4"));
linkedList.add("5");
3. 使用 Stream (JDK8)
List<String> list3 = Stream.of("3", "4").collect(Collectors.toList());
