Java: Divide a string in n equal parts

// Importing necessary Java utilities.
import java.util.*;

// Define a class named Main.
class Main {
    
    // Method to split the string into 'n' parts.
    static void splitString(String str1, int n) {
        // Get the length of the string.
        int str_size = str1.length();
        int part_size;
        
        // Check if the size of the string is divisible by 'n'.
        if (str_size % n != 0) {
            // If not divisible, print a message and return.
            System.out.println("The size of the given string is not divisible by " + n);
            return;
        } else {
            // If divisible, proceed to split the string.
            System.out.println("The given string is: " + str1);
            System.out.println("The string divided into " + n + " parts and they are: ");
            
            // Calculate the size of each part.
            part_size = str_size / n;
            
            // Loop through the string characters.
            for (int i = 0; i < str_size; i++) {
                // If the current index is a multiple of 'part_size', start a new line.
                if (i % part_size == 0)
                    System.out.println();
                // Print the character at the current index.
                System.out.print(str1.charAt(i));
            }
        }
    }
    
    // Main method to execute the program.
    public static void main(String[] args) {
        // Define a string and the number of parts to split.
        String str1 = "abcdefghijklmnopqrstuvwxy";
        int split_number = 5;
        
        // Call the method to split the string.
        splitString(str1, split_number);
    }
}