Convert a for loop to concat String into a lambda expression

Question

I have the following for loop which iterates through a list of strings and stores the first character of each word in a StringBuilder. I would like to know how can

Answer 1

Simple way using method reference :

List list = Arrays.asList("ABC", "CDE");
StringBuilder sb = new StringBuilder();

list.forEach(sb::append);

String concatString = sb.toString();