Best way to convert list to comma separated string in java [duplicate]
You could count the total length of the string first, and pass it to the StringBuilder constructor. And you do not need to convert the Set first.
Set<String> abc = new HashSet<String>();abc.add("A");abc.add("B");abc.add("C");String separator = ", ";int total = abc.size() * separator.length();for (String s : abc) { total += s.length();}StringBuilder sb = new StringBuilder(total);for (String s : abc) { sb.append(separator).append(s);}String result = sb.substring(separator.length()); // remove leading separator
The Separator you are using is a UI component. You would be better using a simple String sep = ", ".