Convert String into comma separated List in Java

Given a String, the task is to convert it into comma separated List.

Examples:

Input: String = "Geeks For Geeks"
Output: List = [Geeks, For, Geeks]

Input: String = "G e e k s"
Output: List = [G, e, e, k, s]

Approach: This can be achieved by converting the String into String Array, and then creating an List from that array. However this List can be of 2 types based on their method of creation – modifiable, and unmodifiable.

• Creating an unmodifiable List:

  // Java program to convert String
  // to comma separated List
  
  import java.util.*;
  
  public class GFG {
      public static void main(String args[])
      {
  
          // Get the String
          String string = "Geeks For Geeks";
  
          // Print the String
          System.out.println("String: " + string);
  
          // convert String to array of String
          String[] elements = string.split(" ");
  
          // Convert String array to List of String
          // This List is unmodifiable
          List<String> list = Arrays.asList(elements);
  
          // Print the comma separated List
          System.out.println("Comma separated List: "
                             + list);
      }
  }
  Output:
  
  

  String: Geeks For Geeks
  Comma separated List: [Geeks, For, Geeks]
  

• Creating a modifiable List:

  // Java program to convert String
  // to comma separated List
  
  import java.util.*;
  
  public class GFG {
      public static void main(String args[])
      {
  
          // Get the String
          String string = "Geeks For Geeks";
  
          // Print the String
          System.out.println("String: " + string);
  
          // convert String to array of String
          String[] elements = string.split(" ");
  
          // Convert String array to List of String
          // This List is modifiable
          List<String>
              list = new ArrayList<String>(
                  Arrays.asList(elements));
  
          // Print the comma separated List
          System.out.println("Comma separated List: "
                             + list);
      }
  }
  Output:

  String: Geeks For Geeks
  Comma separated List: [Geeks, For, Geeks]