How to Join Arrays in Java - Step by Step Examples

How to Join Arrays in Java ?

Answer

To join arrays in Java, you can use the System.arraycopy method or the Arrays.copyOf method along with creating a new array to hold the joined elements.

✐ Examples

1 Join Arrays using System.arraycopy

In this example,

We create two integer arrays named arr1 and arr2 with some elements.
We define the length of the joined array as the sum of the lengths of arr1 and arr2.
We create a new integer array named joinedArr with the defined length.
We use the System.arraycopy method to copy elements from arr1 and arr2 into joinedArr.
Finally, we print the joined array to standard output.

Java Program

import java.util.Arrays;

public class Main {
    public static void main(String[] args) {
        int[] arr1 = {1, 2, 3};
        int[] arr2 = {4, 5, 6};
        int length = arr1.length + arr2.length;
        int[] joinedArr = new int[length];

        System.arraycopy(arr1, 0, joinedArr, 0, arr1.length);
        System.arraycopy(arr2, 0, joinedArr, arr1.length, arr2.length);

        System.out.println(Arrays.toString(joinedArr));
    }
}

Output

[1, 2, 3, 4, 5, 6]

2 Join Arrays using Arrays.copyOf

In this example,

We create two integer arrays named arr1 and arr2 with some elements.
We concatenate the elements of arr1 and arr2 using the Arrays.copyOf method.
We specify the length of the joined array as the sum of the lengths of arr1 and arr2.
We create a new integer array named joinedArr using the concatenated elements.
Finally, we print the joined array to standard output.

Java Program

import java.util.Arrays;

public class Main {
    public static void main(String[] args) {
        int[] arr1 = {1, 2, 3};
        int[] arr2 = {4, 5, 6};
        int[] concatenated = Arrays.copyOf(arr1, arr1.length + arr2.length);
        System.arraycopy(arr2, 0, concatenated, arr1.length, arr2.length);

        System.out.println(Arrays.toString(concatenated));
    }
}

Output

[1, 2, 3, 4, 5, 6]

Summary

In this tutorial, we learned How to Join Arrays in Java language with well detailed examples.

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How to Join Arrays in Java - Step by Step Examples

How to Join Arrays in Java ?

Answer

✐ Examples

1 Join Arrays using System.arraycopy

Java Program

Output

2 Join Arrays using Arrays.copyOf

Java Program

Output

Summary

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