Arrays.fill(Object[], Object) in Java

Arrays.fill(Object[], Object): This method is available in java.util.Arrays class of Java.

Syntax:

void java.util.Arrays.fill(Object[] a, Object val)

This method takes two arguments one of type Object (like Integer, Double, etc) array and the other one of type Object as its parameters. This method assigns the specified Object reference to each element of the specified array of Objects.

Parameters: Two parameters are required for this method.

a: the array to be filled.

val: the value to be stored in all elements of the array.

Returns: NA

Throws:

1. ArrayStoreException - if the specified value is not of a runtime type that can be stored in the specified array.

Approach 1: When no exceptions

Java

import java.util.Arrays;

public class Arraysfillobject {
    public static void main(String[] args) {

        // Object of type Integer
        Integer a[] = new Integer[5];

        int val = 1;

        Arrays.fill(a, val);

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

Output:

[1, 1, 1, 1, 1]

Approach 2: ArrayStoreException

Java

import java.util.Arrays;

public class Arraysfillobject {
    public static void main(String[] args) {

        // Object of type Integer
        Integer a[] = new Integer[5];

        char val = 'a';

        Arrays.fill(a, val);

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

Output:

Exception in thread "main" java.lang.ArrayStoreException: java.lang.Character
	at java.base/java.util.Arrays.fill(Arrays.java:3429)