Java Insert Element into an Array at Index using Apache Commons Lang

In this Java tutorial we learn how to insert an element into an array at a given index using ArrayUtils class of Apache Commons Lang library.

How to add Apache Commons Lang 3 library to your Java project

To use the Apache Commons Lang 3 library in the Gradle build project, add the following dependency into the build.gradle file.

implementation 'org.apache.commons:commons-lang3:3.12.0'

To use the Apache Commons Lang 3 library in the Maven build project, add the following dependency into the pom.xml file.

<dependency>
  <groupId>org.apache.commons</groupId>
  <artifactId>commons-lang3</artifactId>
  <version>3.12.0</version>
</dependency>

To have more information about the Apache Commons Lang 3 library you can visit the library home page at commons.apache.org/proper/commons-lang/

How to Insert Element into Array in Java

The Apache Commons Lang library provides the method ArrayUtils.insert() to insert an element into an array at a specific index (starting from zero).

Below code example shows you how to use the ArrayUtils.insert() with an array of int values.

InsertToArrayInt.java

import org.apache.commons.lang3.ArrayUtils;

public class InsertToArrayInt {
    public static void main(String... args) {
        int[] arrayToInsert = new int[] { 1000, 2000, 3000, 5000 };

        // insert value at index 3
        int[] resultArray = ArrayUtils.insert(3, arrayToInsert, 4000);

        System.out.println("The output int array: ");
        for(int value : resultArray) {
            System.out.println(value);
        }
    }
}

The output is:

The output int array: 
1000
2000
3000
4000
5000

Below code example shows you how to use the ArrayUtils.insert() with an array of long values.

InsertToArrayLong.java

import org.apache.commons.lang3.ArrayUtils;

public class InsertToArrayLong {
    public static void main(String... args) {
        long[] arrayToInsert = new long[] { 111111, 222222, 333333, 555555 };

        // insert value at index 3
        long[] resultArray = ArrayUtils.insert(3, arrayToInsert, 444444);

        System.out.println("The output long array: ");
        for(long value : resultArray) {
            System.out.println(value);
        }
    }
}

The output is:

The output long array: 
111111
222222
333333
444444
555555

Below code example shows you how to use the ArrayUtils.insert() with an array of double values.

InsertToArrayDouble.java

import org.apache.commons.lang3.ArrayUtils;

public class InsertToArrayDouble {
    public static void main(String... args) {
        double[] arrayToInsert = new double[] { 1000.1, 2000.2, 4000.4 };

        // insert value at index 2
        double[] resultArray = ArrayUtils.insert(2, arrayToInsert, 3000.3);

        System.out.println("The output double array: ");
        for(double value : resultArray) {
            System.out.println(value);
        }
    }
}

The output is:

The output double array: 
1000.1
2000.2
3000.3
4000.4

Below code example shows you how to use the ArrayUtils.insert() with an array of float values.

InsertToArrayFloat.java

import org.apache.commons.lang3.ArrayUtils;

public class InsertToArrayFloat {
    public static void main(String... args) {
        float[] arrayToInsert = new float[] { 10.1f, 20.2f, 40.4f };

        // insert value at index 2
        float[] resultArray = ArrayUtils.insert(2, arrayToInsert, 30.3f);

        System.out.println("The output float array: ");
        for(float value : resultArray) {
            System.out.println(value);
        }
    }
}

The output is:

The output float array: 
10.1
20.2
30.3
40.4

Below code example shows you how to use the ArrayUtils.insert() with an array of boolean values.

InsertToArrayBoolean.java

import org.apache.commons.lang3.ArrayUtils;

public class InsertToArrayBoolean {
    public static void main(String... args) {
        boolean[] arrayToInsert = new boolean[] { true, true, true };

        // insert value at index 1
        boolean[] resultArray = ArrayUtils.insert(1, arrayToInsert, false);

        System.out.println("The output boolean array: ");
        for(boolean value : resultArray) {
            System.out.println(value);
        }
    }
}

The output is:

The output boolean array: 
true
false
true
true

Below code example shows you how to use the ArrayUtils.insert() with an array of byte values.

InsertToArrayByte.java

import org.apache.commons.lang3.ArrayUtils;

public class InsertToArrayByte {
    public static void main(String... args) {
        byte[] arrayToInsert = new byte[] { 1, 2, 3, 4, 5 };

        // insert value at index 2
        byte[] resultArray = ArrayUtils.insert(2, arrayToInsert, (byte)0);

        System.out.println("The output byte array: ");
        for(byte value : resultArray) {
            System.out.println(value);
        }
    }
}

The output is:

The output byte array: 
1
2
0
3
4
5

Below code example shows you how to use the ArrayUtils.insert() with an array of char values.

InsertToArrayChar.java

import org.apache.commons.lang3.ArrayUtils;

public class InsertToArrayChar {
    public static void main(String... args) {
        char[] arrayToInsert = new char[] { 'a', 'b', 'c', 'd' };

        // insert value at index 2
        char[] resultArray = ArrayUtils.insert(2, arrayToInsert, 'z');

        System.out.println("The output char array: ");
        for(char value : resultArray) {
            System.out.println(value);
        }
    }
}

The output is:

The output char array: 
a
b
z
c
d

Below code example shows you how to use the ArrayUtils.insert() with an array of short values.

InsertToArrayShort.java

import org.apache.commons.lang3.ArrayUtils;

public class InsertToArrayShort {
    public static void main(String... args) {
        short[] arrayToInsert = new short[] { 100, 200, 300, 500 };

        // insert value at index 3
        short[] resultArray = ArrayUtils.insert(3, arrayToInsert, (short)400);

        System.out.println("The output short array: ");
        for(short value : resultArray) {
            System.out.println(value);
        }
    }
}

The output is:

The output short array: 
100
200
300
400
500

We can also use the method ArrayUtils.insert() with an array of objects, for example String objects.

InsertToArrayString.java

import org.apache.commons.lang3.ArrayUtils;

public class InsertToArrayString {
    public static void main(String... args) {
        String[] arrayToInsert = new String[] { "Simple", "Solution" };

        // insert value at index 1
        String[] resultArray = ArrayUtils.insert(1, arrayToInsert, "Java");

        System.out.println("The output String array: ");
        for(String value : resultArray) {
            System.out.println(value);
        }
    }
}

The output is:

The output String array: 
Simple
Java
Solution

Happy Coding 😊