What are variable length (Dynamic) Arrays in Java?

Java 8Object Oriented ProgrammingProgramming

In Java, Arrays are of fixed size. The size of the array will be decided at the time of creation. But if you still want to create Arrays of variable length you can do that using collections like array list.

Example

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

public class AddingItemsDynamically {
   public static void main(String args[]) {
      Scanner sc = new Scanner(System.in);
      System.out.println("Enter the size of the array :: ");
      int size = sc.nextInt();
      String myArray[] = new String[size];
      System.out.println("Enter elements of the array (Strings) :: ");
      for(int i=0; i<size; i++) {
         myArray[i] = sc.next();
      }
      System.out.println(Arrays.toString(myArray));
      ArrayList<String> myList = new ArrayList<String>(Arrays.asList(myArray));
      System.out.println("Enter the element that is to be added:");
      String element = sc.next();
      myList.add(element);
      myArray = myList.toArray(myArray);
      System.out.println(Arrays.toString(myArray));
   }
}

Output

Enter the size of the array ::
3
Enter elements of the array (Strings) ::
Ram
Rahim
Robert
[Ram, Rahim, Robert]
Enter the element that is to be added:
Mahavir
[Ram, Rahim, Robert, Mahavir]
raja
Published on 09-Jan-2018 11:45:14
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