How to check if an object is an array in Java

Overview

This shot discusses how to determine if the object is an array in Java.

Class class in Java

Java has a class named Class in java.lang package. This class is used for reflection purpose.

Every object in Java belongs to a class. The metadata about the class is captured in the Class object. The metadata can be the class’s constructors, its methods, its fields, and so on.

Therefore, every object belongs to a class and has a Class object. The Class object of any given object can be obtained via the getClass() method.

The isArray() method

The isArray() method of Class is used to check whether an object is an array or not. The method returns true if the given object is an array. Otherwise, it returns false.

Syntax

public boolean isArray();

Parameters

This method takes no parameters.

Example

import java.util.Arrays;
public class Main {
    public static void main(String[] args){
        String stringObject = "educative";
        System.out.printf("Is %s an array - %s", stringObject, stringObject.getClass().isArray());
        System.out.println();
        int[] intArrayObject = new int[4];
        System.out.printf("Is %s an array - %s", Arrays.toString(intArrayObject), intArrayObject.getClass().isArray());
    }
}

Explanation

  • Line 1: We import the Arrays class from the java.util package.
  • Line 3: We define a class Main.
  • Line 5: We define the main method of the Main class.
  • Line 6: We define a string object stringObject.
  • Line 7: We use the isArray() method to determine if stringObject is an array.
  • Line 10: We define an integer array intArrayObject.
  • Line 11: We use the isArray() method to determine if intArrayObject is an array.

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