List 与以逗号分割String类型相互转换

经常使用 List 与以逗号分割String类型相互转换，但是老是会忘记，特意记录下

（1）String转List

String ids= "1,2,3,4,5,6";
List<String> result = Arrays.asList(ids.split(","));

或

String ids= "1,2,3,4,5,6";
List<String> result = Arrays.asList(ids.split("[,.]"));

或

String ids= "1,2,3,4,5,6";
String[] result = ids.split(",");
List<String> list = Arrays.asList(result);

（2）List转String

List<String> result = new ArrayList<>();
result.add("a");
result.add("b");
result.add("c");
String ids = String.join(",", result);

或

List<String> idsList = Arrays.asList("1", "2", "3","4", "5", "6");
String ids = idsList.stream().collect(Collectors.joining(","));