Java - Convert comma-separated String to a List and List to a comma-separated String

In this section, we will show you how to convert comma-separated String to a List and vice versa.

1. Comma-separated String to List

Main.java

import java.util.Arrays;
import java.util.List;

public class Main {
    public static void main(String[] args) {

        String str = "India,USA,Japan,Russia";

        //Remove whitespace and split by comma
        List<String> result = Arrays.asList(str.split("\\s*,\\s*"));

        System.out.println(result);
    }
}


Console Output:
[India, USA, Japan, Russia]

2. List to Comma-separated String

Main.java

import java.util.Arrays;
import java.util.List;

public class Main {
    public static void main(String[] args) {

        List<String> list = Arrays.
                asList("India", "USA", "Japan", "Russia");

        String result = String.join(",", list);
        System.out.println(result);
    }
}


Console Output:
India,USA,Japan,Russia


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