Remove last comma Java using replace all

Question

Is there a ways to delete the last comma from this result?

ID = 1
Name = addsas
Absensi = 20
GajiPokok = 5000000
GajiTotal = 5400000
Tunjangan Makan= 400000
Email = [asdasd,asdasd,]

ID = 4
Name = asdas
Absensi = 20
GajiPokok = 5000000
GajiTotal = 5400000
Tunjangan Makan= 400000
Email = [asdasd,asdas,]

The result I hope is [asdasd,asdas] without comma in the last

Here is my code. Is that because of the while loop that preventing the last comma to be deleted?

        JSONArray email = (JSONArray) jsonObject.get("email");
        @SuppressWarnings("unchecked")
        Iterator<String> it = email.iterator();
        System.out.print("Email = ");
        System.out.print("[");
        String a = "";
        while (it.hasNext()) {
             a = it.next() + ",";
            System.out.print(a.replaceAll(", $", ""));
        }
        System.out.print("]");
        System.out.println("\n");
    }

Answer 1

If you develop in Java 8+ env, you can use stream api to solve such issue:

String result = email.stream().collect(Collectors.joining(","))

Collectors.joining(",") will add comma between items of the list and will omit comma for the very last element.

emails =  List.of("a","b"); 

result = "a,b"; 

emails =  List.of("a"); 

result = "a"; 

it is possible to future enrich the pipeline to add [ and ]

List.of("a").stream().collect(Collectors.joining(",","[","]"))
// produces "[a]"