List转换成以逗号分隔的字符串

List<String> list = Arrays.asList("a", "b", "c", "d", "e");
String collect = list.stream().collect(Collectors.joining(","));
System.out.println("collect = " + collect);

一行代码实现List转换成以逗号分隔的字符串，目前发现最简单的方式