Create formatted string from ArrayList

Question

Consider following code:

    ArrayList aList = new ArrayList();
    aList.add(2134);
    aList.add(3423);
    aList.add(4234);
         


        

Answer 1

Since Java 8 you can also do:

ArrayList<Integer> intList = new ArrayList<Integer>();
intList.add(2134);
intList.add(3423);
intList.add(4234);
intList.add(343);

String prefix = "(";
String infix = ", ";
String postfix = ")";

StringJoiner joiner = new StringJoiner(infix, prefix, postfix);
for (Integer i : intList)
    joiner.add(i.toString());

System.out.println(joiner.toString());