How to Join Elements of ArrayList with Delimiter in Java?

Java – Join Elements of ArrayList<String> with Delimiter

To join elements of given ArrayList<String> arrayList with a delimiter string delimiter, use String.join() method. Call String.join() method and pass the delimiter string delimiter followed by the ArrayList<String> arrayList.

String.join() returns a single string with all the string elements of ArrayList joined with delimiter in between them.

Java Program

import java.util.ArrayList;
import java.util.Arrays;

public class Example {
	public static void main(String[] args) {
		String delimiter = "--";
		ArrayList<String> arrayList = new ArrayList<String>(Arrays.asList("hello", "world", "welcome"));
		String result = String.join(delimiter, arrayList);
		System.out.println("Resulting String:   " + result);
	}
}

Output

Resulting String:   hello--world--welcome

Conclusion

In this Java Tutorial, we learned how to join elements of ArrayList<String> with a specified delimiter in Java.