Example: Anagram Checker (Sorting) in Java

// Anagram Checker (Sorting)
import java.util.Arrays; // Required for Arrays.sort() and Arrays.equals()
import java.util.Scanner;

// Main class containing the entry point of the program
public class Main {

    /**
     * Checks if two strings are anagrams by sorting their characters.
     * Ignores case and non-alphabetic characters.
     *
     * @param str1 The first string.
     * @param str2 The second string.
     * @return true if the strings are anagrams, false otherwise.
     */
    public static boolean areAnagramsUsingSort(String str1, String str2) {
        // Step 1: Handle null or empty strings
        if (str1 == null || str2 == null) {
            return false;
        }
        if (str1.isEmpty() && str2.isEmpty()) {
            return true;
        }

        // Step 2: Normalize strings (remove spaces, convert to lowercase)
        // This makes the comparison case-insensitive and ignores spaces.
        String processedStr1 = str1.replaceAll("\\s", "").toLowerCase();
        String processedStr2 = str2.replaceAll("\\s", "").toLowerCase();

        // Step 3: Check if lengths are different after processing
        if (processedStr1.length() != processedStr2.length()) {
            return false;
        }

        // Step 4: Convert strings to character arrays
        char[] charArray1 = processedStr1.toCharArray();
        char[] charArray2 = processedStr2.toCharArray();

        // Step 5: Sort both character arrays
        Arrays.sort(charArray1);
        Arrays.sort(charArray2);

        // Step 6: Compare the sorted character arrays
        // Arrays.equals() efficiently compares the contents of two arrays
        return Arrays.equals(charArray1, charArray2);
    }

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        System.out.println("--- Anagram Checker (Sorting Method) ---");
        System.out.print("Enter first string: ");
        String s1 = scanner.nextLine();

        System.out.print("Enter second string: ");
        String s2 = scanner.nextLine();

        boolean isAnagram = areAnagramsUsingSort(s1, s2);

        if (isAnagram) {
            System.out.println("\"" + s1 + "\" and \"" + s2 + "\" are anagrams.");
        } else {
            System.out.println("\"" + s1 + "\" and \"" + s2 + "\" are NOT anagrams.");
        }

        scanner.close();
    }
}