How to add an element to an Array in Java?

Given an array of size n, the task is to add an element x in this array in Java.

The size of the array cannot be changed dynamically in Java, as it is done in C/C++. Hence in order to add an element in the array, one of the following methods can be done:

1. By creating a new array:
   • Create a new array of size n+1, where n is the size of the original array.
   • Add the n elements of the original array in this array.
   • Add the new element in the n+1 th position.
   • Print the new array.

   Below is the implementation of the above approach:

   
   
   
   
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   // Java Program to add an element in an Array    import java.io.*; import java.lang.*; import java.util.*;    class GFG {        // Function to add x in arr     public static int[] addX(int n, int arr[], int x)     {         int i;            // create a new array of size n+1         int newarr[] = new int[n + 1];            // insert the elements from         // the old array into the new array         // insert all elements till n         // then insert x at n+1         for (i = 0; i < n; i++)             newarr[i] = arr[i];            newarr[n] = x;            return newarr;     }        // Driver code     public static void main(String[] args)     {            int n = 10;         int i;            // initial array of size 10         int arr[]             = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };            // print the original array         System.out.println("Initial Array:\n"                            + Arrays.toString(arr));            // element to be added         int x = 50;            // call the method to add x in arr         arr = addX(n, arr, x);            // print the updated array         System.out.println("\nArray with " + x                            + " added:\n"                            + Arrays.toString(arr));     } }

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   Output:

   Initial Array:
   [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
   
   Array with 50 added:
   [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 50]
   

2. By using ArrayList as intermediate storage:
   • Create an ArrayList with the original array, using asList() method.
   • Simply add the required element in the list using add() method
   • Convert the list to an array using toArray() method
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   // Java Program to add an element in an Array    import java.io.*; import java.lang.*; import java.util.*;    class GFG {        // Function to add x in arr     public static Integer[] addX(int n, Integer arr[], int x)     {         int i;            // create a new ArrayList         List<Integer> arrlist             = new ArrayList<Integer>(                 Arrays.asList(arr));            // Add the new element         arrlist.add(x);            // Convert the Arraylist to array         arr = arrlist.toArray(arr);            // return the array         return arr;     }        // Driver code     public static void main(String[] args)     {            int n = 10;         int i;            // initial array of size 10         Integer arr[]             = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };            // print the original array         System.out.println("Initial Array:\n"                            + Arrays.toString(arr));            // element to be added         int x = 50;            // call the method to add x in arr         arr = addX(n, arr, x);            // print the updated array         System.out.println("\nArray with " + x                            + " added:\n"                            + Arrays.toString(arr));     } }

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   Output:

   Initial Array:
   [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
   
   Array with 50 added:
   [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 50]
   

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