String ==》List

//方法一
List<String> list = Arrays.asList(str.split(","));

//方法二
List<String> list = Arrays.asList(StringUtils.split(str, ","));

List ==》 String

//StringUtils.join(): 参数一:集合  参数二:连接符     
String join = StringUtils.join(list, "-");

//String.join()
String str = String.join(",", list);

//遍历list集合存入StringBuilder
StringBuilder sb = new StringBuilder();
for(int i = 0;i < list.size();i++){
     sb.append(list.get(i));
 }

//流
String str = list.stream().collect(Collectors.joining(","));

相关文章: