List to string comma separated

List to string comma separated

1. Convert list into comma separated string

String str = String.join(",", list);
 
String str = StringUtils.json(list.toArray(), ",");　　

2. Convert comma separated string to List

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

3. Replace characters in the string

String newStr = str.replace("Character to be replaced", "Target character");