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

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

1. Colon-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 colon
        List<String> result = Arrays.asList(str.split("\\s*:\\s*"));

        System.out.println(result);
    }
}


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

2. List to Colon-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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